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Blood group isoantibody stimulation by feeding blood group active bacteria

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Abstract

It was investigated whether or not the human blood group isoantibodies A and B could be induced by immunogenic stimuli via natural routes with a kind of antigenic substance to which all humans are commonly exposed, or if the appearance of these antibodies is independent of antigenic stimuli as has long been believed. Escherichia coli O(86), which possess high human blood group B and faint A activity in vitro, were fed to healthy humans and those with intestinal disorders. 80% of the sick individuals of blood group O and A responded with a significant rise of anti-B antibodies which was frequently de novo in infants; significant increase of anti-A isoantibodies among blood group O individuals was less frequent. Over one-third of the healthy individuals also had a significant isoantibody increase. Intestinal lesions favor isoantibody stimulation by intestinal bacteria; this view was supported by the study of control infants. Persons of blood group A responded more frequently with anti-B and anti-E. coli O(86) antibody production than those of blood group O. Isoantibody increase was accompanied with antibody rise against E. coli O(86). Inhalation of E. coli O(86) or blood group AH(O)-specific hog mucin also evoked isoantibodies. The induced isoantibodies were specifically inhibited by small amounts of human blood group substances. E. coli O(86)-induced anti-blood group antibodies in germ-free chickens and preexisting blood group antibodies in ordinary chickens were neutralized by intravenous injection of E. coli O(86) lipopolysaccharide. This study demonstrates that human isoantibodies A and B are readily elicited via physiological routes, by blood group-active E. coli, provided the genetically determined apparatus of the host is responsive. Antibodies against a person's own blood group were not formed. Interpretation of these results permits some careful generalizations as to the origin of so-called natural antibodies.

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... Isoantibodies, also referred as isohaemagglutinins, are anti-A, anti-B and anti-AB antibodies which develope during the first year of life [52][53][54][55] . The name isoantibody comes from the fact that they are raised by each individual against their own species antigens, termed isoantigens. ...
... The name isoantibody comes from the fact that they are raised by each individual against their own species antigens, termed isoantigens. Biosynthesis of naturally occurring isoantibodies against blood group antigens A and B is induced as a response to either intestinal bacterial infection, viral infections and or plantfood [52][53][54][55] . Isoantibodies are detected approximately 4 to 6 month after birth. ...
... Isoantibodies are detected approximately 4 to 6 month after birth. Between 5 and 10 years of age their concentration raises to normally occurring levels [52][53][54][55] . Diets contain always different kinds of bacteria. ...
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... These antibodies include a panel of carbohydrate-reactive antibodies, such as anti-laminaribioside, anti-mannobioside, anti-chitobioside, anti-laminarin and anti-chitin (Dotan et al., 2006;Rieder et al., 2010;Kaul et al., 2012;Paul et al., 2015). Exposure to surface glycans of intestinal bacteria triggers the production of carbohydrate-specific antibodies (Springer et al., 1961;Springer and Horton, 1969;Macher and Galili, 2008;Yilmaz et al., 2014;Bello-Gil et al., 2019). Some bacterial and mammalian glycans share antigenic properties, for example AB0 blood group antigens, which stimulate the production of AB0-specific antibodies during the first months of life after microbial colonization of the gastrointestinal tract (Springer and Horton, 1969;Dean, 2005). ...
... Exposure to surface glycans of intestinal bacteria triggers the production of carbohydrate-specific antibodies (Springer et al., 1961;Springer and Horton, 1969;Macher and Galili, 2008;Yilmaz et al., 2014;Bello-Gil et al., 2019). Some bacterial and mammalian glycans share antigenic properties, for example AB0 blood group antigens, which stimulate the production of AB0-specific antibodies during the first months of life after microbial colonization of the gastrointestinal tract (Springer and Horton, 1969;Dean, 2005). Specific bacteria mimic host glycan structures to evade recognition by the immune system (Moran et al., 1996;Comstock and Kasper, 2006). ...
Article
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Inflammatory bowel disease is associated with intestinal dysbiosis and with elevated antibody production toward microbial epitopes. The underlying processes linking the gut microbiota with inflammation are still unclear. Considering the constant induction of antibodies by gut microbial glycans, the aim of this study was to address whether the repertoire of carbohydrate-specific antibodies is altered in Crohn’s disease or ulcerative colitis. IgG and IgM reactivities to oligosaccharides representative of mucosal glycans were tested in blood serum from 20 healthy control subjects, 17 ulcerative colitis patients, and 23 Crohn’s disease patients using glycan arrays. An increased IgG and IgM reactivity toward fucosylated oligosaccharides was detected in Crohn’s disease but not in ulcerative colitis. To address the antibody reactivity to the gut microbiota, IgG binding to members of a complex intestinal microbiota was measured and observed to be increased in sera of patients with Crohn’s disease. Based on the elevated reactivity to fucosylated oligosaccharides, gut bacteria were tested for recognition by the fucose-binding Aleuria aurantia lectin. Bacteroides stercoris was detected in IgG- and lectin-positive fractions and reactivity of A. aurantia lectin was demonstrated for additional Bacteroides species. IgG reactivity to these Bacteroides species was significantly increased in inflammatory bowel disease patients, indicating that the increased reactivity to fucosylated oligosaccharides detected in Crohn’s disease may be induced by fucose-carrying intestinal bacteria. Enhanced antibody response to fucosylated epitopes may have systemic effects by altering the binding of circulating antibodies to endogenous glycoproteins.
... Several studies have also shown the synthesis of anti-carbohydrate antibodies in response to O-antigens and lipopolysaccharide antigens of gastrointestinal bacteria [Springer and Horton, 1969]. Dietary food components may also be a potential stimulant for the production of anti-carbohydrate antibodies e.g. ...
... Since anti-carbohydrate antibodies occur naturally, their serum concentrations vary amongst individuals depending on the intestinal microbial flora, diet and pathogen exposure [Springer and Horton, 1969;Bos et al., 1989]. Titre of plasma anti-glycan antibodies specific to desialylated glycoconjugates was assayed by polyagglutination. ...
Thesis
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In this thesis I demonstrate a novel mechanism of immunopathology associated with desialylation and described desialylation and subsequent immune complex formation as a potential route for tissue deposition of lipoproteins. Desialylation (loss of terminal sialic acids from N- and O-glycans) of Lp(a) led to immune complex formation with autologous anti-glycan antibodies found in circulation, such as lactose-binding antibody and Anti-T antibody. These multivalent antibodies that formed immune complexes were found to retain free binding sites and could bind to desialylated cell surfaces, subsequently leading to tissue deposition of Lp(a). Atherosclerosis is a progressive disease of large- and medium-sized arteries and is a major cause of mortality and morbidity in cerebrovascular and cardiovascular diseases. Among several genetic and non-genetic risk factors identified, high plasma levels of lipoprotein(a) (Lp(a)) (a heavily glycosylated polymorphic lipoprotein) has been implicated as an independent risk factor leading to atheroma formation. However, molecular events that lead to deposition of Lp(a) in the vascular tissue was unknown. My work demonstrated a role of glycans in promoting Lp(a) pathology.
... At the age of 8 months, infants express B1 and B2 cell-derived ABO antibodies, thus indicating the maturation of specific antibodies to these antigens beyond natural antibodies [98]. The presence of B2 cell-derived ABO antibodies underlines the antibody maturation process driven by gut bacterial stimulation [100][101][102]. The same principle has been suggested for the production of α-Gal-specific antibodies [25,43]. ...
... Colonization of mice deficient for the α1-3 Gal-transferase Ggta1 with E. coli O86:B7 resulted in the production of α-Gal IgM [104]. Similarly, the ingestion of E. coli O86:B7 in humans triggered the production of antibodies to blood group B antigen, which includes an epitope related to α-Gal [101] (Fig. 4a). A correlation between the composition of the gut microbiota and carbohydrate-specific antibodies was reported in Ggta1-null mice, in which changes in Clostridiales, Bacteroidales, Lactobacillales, and Deferribacterales were related to changes in the levels and repertoires of carbohydrate-specific antibodies [105]. ...
Article
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Carbohydrate-specific antibodies are widespread among all classes of immunoglobulins. Despite their broad occurrence, little is known about their formation and biological significance. Carbohydrate-specific antibodies are often classified as natural antibodies under the assumption that they arise without prior exposure to exogenous antigens. On the other hand, various carbohydrate-specific antibodies, including antibodies to ABO blood group antigens, emerge after the contact of immune cells with the intestinal microbiota, which expresses a vast diversity of carbohydrate antigens. Here we explore the development of carbohydrate-specific antibodies in humans, addressing the definition of natural antibodies and the production of carbohydrate-specific antibodies upon antigen stimulation. We focus on the significance of the intestinal microbiota in shaping carbohydrate-specific antibodies not just in the gut, but also in the blood circulation. The structural similarity between bacterial carbohydrate antigens and surface glycoconjugates of protists, fungi and animals leads to the production of carbohydrate-specific antibodies protective against a broad range of pathogens. Mimicry between bacterial and human glycoconjugates, however, can also lead to the generation of carbohydrate-specific antibodies that cross-react with human antigens, thereby contributing to the development of autoimmune disorders.
... When comparing our k-medoids results to our microbial pathogen sequence correlation data, we also observed that the RBC antigen immunogenicity clusters followed a trend similar to our immunogenicity-microbial genera correlation, raising the question of a mechanistic link. Exposure to environmental pathogens and commensal bacteria has long been implicated in shaping our immune systems in the formation of ABO-group antibodies, 12 and more recently to the development of antigen specific Th17-type immune responses in mouse models of autoimmune disease, [13][14][15] as well as a potential role in humans. 16 These serve as just a few examples of how surrounding microbes interact with and shape our immune responses, and highlight the importance of examining this potential relationship in a prospectively-designed, future experiment. ...
Article
BACKGROUND It is well known that specific groups of patients immunologically respond more readily than others to red blood cell (RBC) antigens. While allogeneic RBC antigen exposure is the primary determinant of alloantibody formation, other variables are also involved. Given the significant primary sequence identity between common RBC and microbial antigens, we hypothesized that certain individuals may be immunologically primed to form RBC alloantibodies via environmental exposure to cross‐reactive microbial epitopes, and that such a correlation may be linked to blood group antigen immunogenicity. STUDY DESIGN AND METHODS We examined the relationship between RBC‐microbe peptide homology and the formation of alloantibodies to the most immunogenic RBC antigens, using the BLASTp homology database. Thirteen‐residue peptides centered on the polymorphic amino acids of K, Jka, Lua, E, c, M, C, and S antigens were queried for identity with microbial peptides using the BLASTp database. Results were restricted to bacteria and fungi, with a selective threshold of >80% identity for inclusion, to allow for minor peptide variability. RESULTS Significant peptide identity was found between RBC antigens and pathogenic organisms including B. fragilis, P. aeruginosa, and Candida spp., among others. Linear regression and k‐medoids clustering analysis of the microbial genera meeting the inclusion criteria showed a statistically significant inverse correlation with RBC immunogenicity (b = −0.0017, r² = 0.624 & p = 0.0197), with lower immunogenicity antigens associated with larger number of genera. CONCLUSIONS Our findings raise a potential relationship between microbial exposure and alloantibody formation, and lead to interesting questions regarding the potential relationship between RBC antigen immunogenicity and microbial prevalence.
... The homozygosity for the lack of these glycosyltransferases confers the unmodified H antigen, called blood group O. During development, blood group O individuals develop anti-A and anti-B antibodies, whereas blood group A and B ones develop anti-B or anti-A antibodies, respectively [71]. Individuals with both alleles, AB, will not develop any of these anti-glycan antibodies. ...
Article
Glycans are carbohydrates that are made by all organisms and covalently conjugated to other biomolecules. Glycans cover the surface of both human cells and pathogens and are fundamental to defining the identity of a cell or an organism, thereby contributing to discriminating self from non‐self. As such, glycans are a class of “Self‐Associated Molecular Patterns” that can fine‐tune host inflammatory processes. In fact, glycans can be sensed and recognized by a variety of glycan‐binding proteins (GBP) expressed by immune cells, such as galectins, siglecs and C‐type lectins, which recognize changes in the cellular glycosylation, instructing both pro‐inflammatory or anti‐inflammatory responses. In this review, we introduce glycans as cell‐identification structures, discussing how glycans modulate host‐pathogen interactions and how they can fine‐tune inflammatory processes associated with infection, inflammation and autoimmunity. Finally, from the clinical standpoint, we discuss how glycoscience research can benefit life sciences and clinical medicine by providing a source of valuable biomarkers and therapeutic targets for immunity. Glycans have an enormous power to discriminate self/non‐self as they constitute a fundamental molecular ID of both human cells and pathogens. We discuss the concept of glycan mimicry associated with the breach of immune tolerance and the potential application of glycans as promising diagnostic/prognostic biomarkers or as novel immunomodulatory therapies against infections and autoimmune diseases.
... O alleles in the homozygote state confer blood group O, which is characterized by a complete absence of A or B antigens [5]. Under stimulation by bacteria of the microbiota that present glycan motifs similar to either A or B antigens, blood group O people develop so-called "natural" anti-A and anti-B antibodies, whilst blood group A and B individuals develop either anti-B or anti-A antibodies, respectively [6]. Only people of the AB subgroup lack such antibodies. ...
... Consistent with this, recent studies demonstrate that IgM antibody levels and repertoire develop independently of microbial exposure; germfree mice produce a similar level and breadth of antibody specificities as occurs in conventionally housed mice [111]. Other studies suggested that microbial exposure may enhance anti-blood group antibody formation [112,113]. However, whether microbial exposure is required for anti-A or anti-B antibody formation or simply enhances existing antibody production remains unclear. ...
Article
The ABH and Lewis antigens were among the first of the human red blood cell polymorphisms to be identified and, in the case of the former, play a dominant role in transfusion and transplantation. But these two therapies are largely twentieth century innovations, and the ABH and related carbohydrate antigens are not only expressed on a very wide range of human tissues, but were present in primates long before modern humans evolved. Although we have learned a great deal about the biochemistry and genetics of these structures, the biological roles that they play in human health and disease are incompletely understood. This review and its companion, to appear in a later issue of Vox Sanguinis, will focus on a few of the biologic and pathologic processes which appear to be affected by histo‐blood group phenotype. The first of the two reviews will explore the interactions of two bacteria with the ABH and Lewis glycoconjugates of their human host cells, and describe the possible connections between the immune response of the human host to infection and the development of the AB‐isoagglutinins. The second review will describe the relationship between ABO phenotype and thromboembolic disease, cardio‐vascular disease states, and general metabolism.
... There are four main differences between immunization against Neu5Gc and other xenoglycans, such as the disaccharide alpha-Gal, or alloglycans such as ABO oligosaccharide antigens. First, in the case of other xenoglycans, immunization against the missing, terminal "self "-glycan is thought to be caused by encounters with microbial glycans with the same structure (31,32). Considering that the synthesis of endogenous Neu5Gc has never been documented for any microbe, it would appear unlikely that this microbial priming method occurs for Neu5Gc (33,34). ...
Article
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The glycocalyx of human cells differs from that of many other mammals by the lack of the sialic acid N-glycolylneuraminic acid (Neu5Gc) and increased abundance of its precursor N-acetylneuraminic acid (Neu5Ac). Most humans also have circulating antibodies specifically targeting the non-human sialic acid Neu5Gc. Recently, several additional mammalian species have been found to also lack Neu5Gc. In all cases, loss-of-function mutations in the gene encoding the sialic acid-modifying enzyme CMAH are responsible for the drastic change in these species. Unlike other glycan antigens, Neu5Gc apparently cannot be produced by microbes, raising the question about the origin of these antibodies in humans. Dietary exposure and presentation on bacteria coating themselves with Neu5Gc from the diet are distinct possibilities. However, the majority of the non-human species that lack Neu5Gc do not consume diets rich in Neu5Gc, making it unlikely that they will have been immunized against this sialic acid. A notable exception are mustelids (ferrets, martens and their relatives) known for preying on various small mammal species rich in Neu5Gc. No studies exist on levels of anti-Neu5Gc antibodies in non-human species. Evolutionary scenarios for the repeated, independent fixation of CMAH loss-of-function mutations at various time points in the past include strong selection by parasites, especially enveloped viruses, stochastic effects of genetic drift, and directional selection via female immunity to paternal Neu5Gc. Convergent evolution of losses of the vertebrate-specific self-glycan Neu5Gc are puzzling and may represent a prominent way in which glycans become agents of evolutionary change in their own right. Such change may include the reconfiguration of innate immune lectins that use self-sialic acids as recognition patterns.
... Most of these antibodies target carbohydrate structures and its origin, repertoire, and physiological role are still controversial (19). The most accepted origin hypothesis suggests that stimulation of B-1 lymphocytes is produced by exposition to antigenic determinants of the gut microbiota (20). The differences observed in the composition of circulating anti-glycan NAbs in BALB/c mice (15), also reflect the uncertainties about the physiological role and origin of these antibodies. ...
Article
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Gut commensal bacteria are known to have a significant role in regulating the innate and adaptive immune homeostasis. Alterations in the intestinal microbial composition have been associated with several disease states, including autoimmune and inflammatory conditions. However, it is not entirely clear how commensal gut microbiota modulate and contribute to the systemic immunity, and whether circulating elements of the host immune system could regulate the microbiome. Thus, we have studied the diversity and abundance of specific taxons in the gut microbiota of inbred GalT-KO mice during 7 months of animal life by metagenetic high-throughput sequencing (16S rRNA gene, variable regions V3–V5). The repertoire of glycan-specific natural antibodies, obtained by printed glycan array technology, was then associated with the microbial diversity for each animal by metagenome-wide association studies (MWAS). Our data show that the orders clostridiales (most abundant), bacteriodales, lactobacillales, and deferribacterales may be associated with the development of the final repertoire of natural anti-glycan antibodies in GalT-KO mice. The main changes in microbiota diversity (month-2 and month-3) were related to important changes in levels and repertoire of natural anti-glycan antibodies in these mice. Additionally, significant positive and negative associations were found between the gut microbiota and the pattern of specific anti-glycan antibodies. Regarding individual features, the gut microbiota and the corresponding repertoire of natural anti-glycan antibodies showed differences among the examined animals. We also found redundancy in different taxa associated with the development of specific anti-glycan antibodies. Differences in microbial diversity did not, therefore, necessarily influence the overall functional output of the gut microbiome of GalT-KO mice. In summary, the repertoire of natural anti-carbohydrate antibodies may be partially determined by the continuous antigenic stimulation produced by the gut bacterial population of each GalT-KO mouse. Small differences in gut microbiota diversity could determine different repertoire and levels of natural anti-glycan antibodies and consequently might induce different immune responses to pathogens or other potential threats.
... The role of microbiota in the induction of anti-a-Gal Abs has been experimentally evaluated. Gut colonization by E. coli O86: B7 elicited anti-a-Gal Abs in a1,3GT-deficient mice (57), humans (70), primates (71), white Leghorn chicks (72), and turkeys (30). Modulation of anti-a-Gal immunity using gut microbiota manipulation protects birds against avian aspergillosis, caused by experimental infection with A. fumigatus (30). ...
Article
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Aspergillosis is a fungal infection caused mainly by Aspergillus fumigatus that often results in respiratory disease in birds. Aspergillosis is a major cause of morbidity and mortality in managed penguin species. Currently, there is no registered vaccine to prevent aspergillosis. Recent research demonstrated that oral administration of gram-negative bacteria expressing high levels of galactose-α-1,3-galactose (α-Gal) modulates anti-α-Gal immunity and protectes turkeys from clinical aspergillosis caused by experimental A. fumigatus infection. The role of anti-α-Gal immunity in penguins has not been studied. Here, we tested the distribution of α-1,3-galactosyltransferase (α1,3GT) genes in the fecal microbiome of Humboldt penguins (Spheniscus humboldti). The occurrence of natural anti-α-Gal antibodies (Abs) in sera and eggs of healthy Humboldt penguins was also assessed. A trial was then conducted to test whether oral administration of Escherichia coli Nissle, expressing high α-Gal levels, modulated anti-α-Gal immunity in a colony of managed Humboldt penguins. Animals in the vaccination and placebo groups were evaluated before the trial and followed for one year for aspergillosis detection using a diagnostic panel including computed tomography scans, capillary zone electrophoresis, 3-hydroxybutyrate levels, and anti-A. fumigatus Abs. Anti-α-Gal Abs were detected in sera (IgM and IgY) and eggs (IgY) of healthy penguins. Microbiota analysis and functional predictions revealed the presence of α1,3GT genes in the microbiota of Humboldt penguins and other penguin species. A strong decrease of anti-α-Gal IgM levels was observed in all animals in the placebo group three months after vaccination protocol. This decrease was not observed in E. coli Nissle-treated penguins. After the vaccination protocol, we found a positive correlation between anti-E. coli IgY and anti-α-Gal IgY in the E. coli Nissle group, suggesting a correlation between the presence of the bacteria and these Abs. During the study period, three penguins exhibited respiratory signs consistent with aspergillosis. Two were from the placebo group whose symptoms resolved with specific treatments, while a single vaccinated individual developed fatal respiratory aspergillosis eight months after the trial. We conclude that E. coli Nissle represents a safe potential probiotic with protective effect against aspergillosis in Humboldt penguins that deserves to be further explored for therapeutic use.
... We demonstrate that there is no relationship between an increasing ABO-antibody titre and cRF, reflecting the biological distinction between antigen exposure and the development of antibodies incurred in ABO & HLA. ABO antibodies may be 'naturally' generated as a crossreactive consequence to pathogen exposure within the gut [22], while development of anti-HLA antibody requires the prior inoculation of the immune system with the antigen as a result of prior transplantation, pregnancy or transfusion. permitting low antibody level ABOi allocation, (c) SIM2as for SIM1, but restricting blood group B donors to be allocated to blood group A recipients only if they are 000 HLA mismatch (d) SIM3 as for SIM1, but only permitting blood group B donors to be allocated to blood group B recipients. ...
Article
Blood group O or B recipients wait longer for a kidney transplant. We studied the distribution of anti‐ABO blood group antibody titres in patients awaiting a kidney transplant, and modelled the effect of altering the UK National Kidney Allocation Scheme to allow for patients with ‘LOW’ titres (≤1:8, ≤3 dilutions) to receive a deceased donor ABOi (ddABOi) transplant. In a prospective study of 239 adult patients on the waiting list for a transplant in 2 UK centres, ABO‐antibody titres (anti‐A and anti‐B) were measured. Based on the proportions of ‘LOW’ anti‐A or anti‐B antibodies, 4 simulations were performed to model the current allocation rules compared to variations allowing ddABOi allocation under various conditions of blood group, HLA matching and waiting time. The simulations permitting ddABOi resulted in more blood group B recipients being transplanted, with median waiting time reduced for this group of recipients, and more equitable waiting times across blood groups. Additionally, permitting ddABOi resulted in greater numbers of 000MM allocations overall in compatible transplants under modelled conditions. Changing allocation in the UK to permit ddABOi in patients with ‘LOW’ titres would not change the total number of transplants, but redistributes allocation more equitably amongst blood groups, altering waiting times accordingly. This article is protected by copyright. All rights reserved.
... Their presence may be a microbial strategy to evade the immune defense in the host in accordance with the molecular mimicry concept. 47 The human anti-Fs are mainly of IgM type, but there may also be a component of IgG. 48,49 Svensson et al. 30 reported crossmatch reactivity with FORS1+ ...
... Their presence may be a microbial strategy to evade the immune defense in the host in accordance with the molecular mimicry concept. 47 The human anti-Fs are mainly of IgM type, but there may also be a component of IgG. 48,49 Svensson et al. 30 reported crossmatch reactivity with FORS1+ ...
... It has been shown that the post-natal appearance of anti-carbohydrate antibodies, such as anti-Gal [29], anti-Neu5Gc [30], and anti-blood group [33] antibodies, is elicited by colonizing gut bacteria expressing these epitopes during infancy in humans. Therefore, we anticipated that there would be a positive correlation between anti-Gal and anti-Neu5Gc antibody levels in humans. ...
Article
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Our group previously investigated the levels of anti-Gal and anti-nonGal IgM and IgG in a cohort of 75 healthy humans of various backgrounds, and found some significant differences related to factors such as age, gender, ABO blood group, diet, vaccination history, and geographic location during childhood. We have now expanded our cohort (n = 84) to investigate the levels of anti-Neu5Gc and anti-nonGal/nonNeu5Gc antibodies in healthy humans. Anti-nonGal and anti-nonGal/nonNeu5Gc human IgM and IgG binding to pRBCs and pAECs from GTKO/CD46 and GTKO/CD46/Neu5GcKO pigs were measured by flow cytometry. Anti-Gal and anti-Neu5Gc IgM and IgG levels were measured by ELISA. In summary, (i) the great majority (almost 100%) of humans had anti-Neu5Gc IgM and IgG antibodies that bound to pAECs and approximately 50% had anti-Neu5Gc antibodies that bound to pRBCs, (ii) there was significantly less human antibody binding to pig cells that did not express either Gal or Neu5Gc compared with those that did not express Gal alone, (iii) the levels of both IgM and IgG binding to GTKO/CD46/Neu5GcKO pRBCs and pAECs were low, (iv) the level of anti-Neu5Gc IgG was higher in men than women, (v) the level did not change with age or diet, and there was some variability associated with (vi) previous vaccination history and (vii) the geographic region in which the individual spent his or her childhood. Our study confirms that human antibody binding to RBCs and AECs from GTKO/CD46/Neu5GcKO pigs is greatly reduced compared to binding to GTKO/CD46 cells. However, all humans appear to have a low level of antibody that binds to pAECs that is not directed to either Gal or Neu5Gc. Our findings require consideration in planning clinical trials of xenotransplantation.
... In fact, A-allelic, phenotypespecific GalNAc glycosylation of plasma proteins does not occur in human blood group O, affecting anti-Tn antibody levels, which may function as a growth regulator that contributes to a potential survival advantage of this group in the overall risk of developing cancer when compared with non-O blood groups. many anti-glycan antibodies do not adhere to the paradigm of an adaptive immune response and are often referred to as " natural antibodies "[4], to date, based on the historical experiments of Springer et al.[5][6][7], the production of human histo-blood group ABO(H) isoantibodies or isoagglutinins with Tn and T antigen crossspecificity is believed to be exclusively induced by environmental, predominantly intestinal, well-documented microbial antigens, particularly lipopolysaccharides from gram-negative bacteria. However, prokaryotic " blood group A/B-like " antigenic structures basically induce cross-reactive anti-A/B immunoglobulins, which due to clonal selection neither arise in blood group A nor in B individuals. ...
Article
While native blood group A-like glycans have not been demonstrated in prokaryotic microorganisms as a source of human "natural" anti-A isoagglutinin production, and metazoan eukaryotic N-acetylgalactosamine O-glycosylation of serine or threonine residues (O-GalNAc-Ser/Thr-R) does not occur in bacteria, the O-GalNAc glycan-bearing ovarian glycolipids, discovered in C57BL/10 mice, are complementary to the syngeneic anti-A-reactive immunoglobulin M (IgM), which is not present in animals that have undergone ovariectomy prior to the onset of puberty. These mammalian ovarian glycolipids are complementary also to the anti-A/Tn cross-reactive Helix pomatia agglutinin (HPA), a molluscan defense protein, emerging from the coat proteins of fertilized eggs and reflecting the snail-intrinsic, reversible O-GalNAc glycosylations. The hexameric structure of this primitive invertebrate defense protein gives rise to speculation regarding an evolutionary relationship to the mammalian nonimmune, anti-A-reactive immunoglobulin M (IgM) molecule. Hypothetically, this molecule obtains its complementarity from the first step of protein glycosylations, initiated by GalNAc via reversible O-linkages to peptides displaying Ser/Thr motifs, whereas the subsequent transferase depletion completes germ cell maturation and cell renewal, associated with loss of glycosidic bonds and release of O-glycan-depleted proteins, such as complementary IgM revealing the structure of the volatilely expressed "lost" glycan carrier through germline Ser residues. Consequently, the evolutionary/developmental first glycosylations of proteins appear metabolically related or identical to that of the mucin-type, potentially "aberrant" monosaccharide GalNAcα1-O-Ser/Thr-R, also referred to as the Tn (T "nouvelle") antigen, and explain the anti-Tn cross-reactivity of human innate or "natural" anti-A-specific isoagglutinin and the pronounced occurrence of cross-reactive anti-Tn antibody in plasma from humans with histo-blood group O. In fact, A-allelic, phenotype-specific GalNAc glycosylation of plasma proteins does not occur in human blood group O, affecting anti-Tn antibody levels, which may function as a growth regulator that contributes to a potential survival advantage of this group in the overall risk of developing cancer when compared with non-O blood groups.
... e α-Gal epitope is structurally closely related to the blood group B antigen [9]. Only the lack of a fucose residue on the glycan core distinguishes the structure of blood group B antigen from α-Gal [23]. Subjects with blood groups B and AB have been shown to produce natural anti-α-Gal antibodies that bind to α-Gal epitopes only; whereas subjects with blood groups A or O have antibodies that react to either α-Gal or B antigen [24,25]. ...
Article
In the last decade, a novel type of food allergy presenting with severe allergic reactions several hours after consumption of red meat has been recognized. The allergic responses are due to IgE antibodies directed against the carbohydrate epitope galactose-α-1,3-galactose (α-Gal) found in mammalian meat. This review presents the red meat allergy syndrome in Sweden, discusses the features of the immune response to carbohydrates, and highlights the presence of heat stable α-Gal-containing proteins in meat. The number of diagnosed red meat allergy cases in Sweden has increased significantly over the past few years. All patients have been tick bitten. Our recent work has shown that α-Gal is present in the European tick Ixodes ricinus (I. ricinus), thus potentially explaining the strong association between anti-α-Gal IgE and tick bites, with development of red meat allergy as a secondary phenomenon. Further studies using immunoproteomics have identified novel α-Gal-containing meat proteins that bound IgE from red meat allergic patients. Four of these proteins were stable to thermal processing pointing to the fact that the allergenicity of red meat proteins is preserved in cooked meat. In keeping with the fact that the α-Gal epitope is structurally related to the blood group B antigen, a positive association with the B-negative blood groups among our red meat allergic patients was noted. A selective IgE reactivity to the pure carbohydrate moiety was observed when investigating the specificity of the α-Gal immune response. IgE from red meat allergic patients does not recognize the other major mammalian carbohydrate, N-glycolylneuraminic acid (Neu5Gc), also present in high amounts in red meat. Furthermore, neither common cross-reactive carbohydrate determinants (CCDs) from plants nor venoms are targets of the IgE response in these patients. Taken together, the α-Gal carbohydrate has shown to be a potentially clinically relevant allergen that should be taken into account in the diagnosis of food allergy. Many new findings in the field of red meat allergy have been obtained during the past years, but further efforts to understand the process of digestion, absorption, and delivery of α-Gal-containing molecules to the circulation are needed.
... Similar to blood group O or B humans, WT B6 mice developed natural anti-A antibodies with age, although this appeared more delayed in mice than humans. Production of natural ABO antibodies in humans is presumed to be cross-reactive immunity to similar epitopes on gut bacteria, 33 and this may also be the case with WT mice. It remains to be tested whether mice housed in less clean conditions would develop natural anti-A more rapidly and/or at higher titers than reported here. ...
Article
Background: ABO-incompatible (ABOi) organ transplantation is performed owing to unremitting donor shortages. Defining mechanisms of antibody-mediated rejection, accommodation, and tolerance of ABOi grafts is limited by lack of a suitable animal model. We report generation and characterization of a murine model to enable study of immunobiology in the setting of ABOi transplantation. Methods: Transgenesis of a construct containing human A1- and H-transferases under control of the ICAM-2 promoter was performed in C57BL/6 (B6) mice. A-transgenic (A-Tg) mice were assessed for A-antigen expression by histology and flow cytometry. B6 wild-type (WT) mice were sensitized with blood group A-human erythrocytes; others received passive anti-A monoclonal antibody and complement after heart transplant. Serum anti-A antibodies were assessed by hemagglutination. "A-into-O" transplantation (major histocompatibility complex syngeneic) was modeled by transplanting hearts from A-Tg mice into sensitized or nonsensitized WT mice. Antibody-mediated rejection was assessed by morphology/immunohistochemistry. Results: A-Tg mice expressed A-antigen on vascular endothelium and other cells including erythrocytes. Antibody-mediated rejection was evident in 15/17 A-Tg grafts in sensitized WT recipients (median titer, 1:512), with 2 showing hyperacute rejection and rapid cessation of graft pulsation. Hyperacute rejection was observed in 8/8 A-Tg grafts after passive transfer of anti-A antibody and complement into nonsensitized recipients. Antibody-mediated rejection was not observed in A-Tg grafts transplanted into nonsensitized mice. Conclusions: A-Tg heart grafts transplanted into WT mice with abundant anti-A antibody manifests characteristic features of antibody-mediated rejection. These findings demonstrate an effective murine model to facilitate study of immunologic features of ABOi transplantation and to improve potential diagnostic and therapeutic strategies.
... In the case of polysaccharides, human anti-glycan antibodies, including anti-A/B allo-agglutinins, antibodies to glycoprotein O-chain glycans Galβ1-3GalNAcα (TF) and GalNAcα (Tn), are risen due to contact of the newborn immune system with intestinal microbiota (34,35). Pivotal role in this phenomenon might play bacterial polysaccharides, structure of which mimics ABH blood groups (7,36), TF/Tn or other related mammalian glycans (37,38). From the moment of birth, the gastrointestinal tract and respiratory system in mammals are actively colonized by bacteria. ...
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One of the most common genetic backgrounds for mice used as a model to investigate human diseases is the inbred BALB/c strain. This work is aimed to characterize the pattern of natural anti-carbohydrate antibodies present in the serum of 20 BALB/c mice by printed glycan array technology and to compare their binding specificities with that of human natural anti-carbohydrate antibodies. Natural antibodies (NAbs) from the serum of BALB/c mice interacted with 71 glycans from a library of 419 different carbohydrate structures. However, only seven of these glycans were recognized by the serum of all the animals studied, and other five glycans by at least 80% of mice. The pattern of the 12 glycans mostly recognized by the circulating antibodies of BALB/c mice differed significantly from that observed with natural anti-carbohydrate antibodies in humans. This lack of identical repertoires of natural anti-carbohydrate antibodies between individual inbred mice, and between mice and humans, should be taken into consideration when mouse models are intended to be used for investigation of NAbs in biomedical research.
... Bacteria from human gut microbiota also express α-Gal on their surface and a continuous antigenic stimulation produce serum accumulation of natural anti-α-Gal immunoglobulins G (IgG) and IgM [3,5]. Gut colonization by the bacterium Escherichia coli O86:B7 [6], which expresses high levels of α-Gal [7,8], elicits the production of Abs with reactivity to α-Gal and α-Gal-related B blood group glycan in α-Gal-deficient mice [9], non-human primates [10], chickens [11] and humans [12]. ...
Article
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Naturally occurring human antibodies (Abs) of the isotypes IgM and IgG and reactive to the galactose-α-1,3-galactose (α-Gal) epitope are associated with protection against infectious diseases, caused by pathogens expressing the glycan. Gut microbiota bacteria expressing α-Gal regulate the immune response to this glycan in animals lacking endogenous α-Gal. Here, we asked whether the production of anti-α-Gal Abs in response to microbiota stimulation in birds, confers protection against infection by Aspergillus fumigatus, a major fungal pathogen that expresses α-Gal in its surface. We demonstrated that the oral administration of Escherichia coli O86:B7 strain, a bacterium with high α-Gal content, reduces the occurrence of granulomas in lungs and protects turkeys from developing acute aspergillosis. Surprisingly, the protective effect of E. coli O86:B7 was not associated with an increase in circulating anti-α-Gal IgY levels, but with a striking reduction of anti-α-Gal IgA in the lungs of infected turkeys. Subcutaneous immunization against α-Gal did not induce a significant reduction of lung anti-α-Gal IgA and failed to protect against an infectious challenge with A. fumigatus. Oral administration of E. coli O86:B7 was not associated with the upregulation of lung cytokines upon A. fumigatus infection. We concluded that the oral administration of bacteria expressing high levels of α-Gal decreases the levels of lung anti-α-Gal IgA, which are mediators of inflammation and lung damage during acute aspergillosis.
... Mice remained healthy and active, with no detectable weight loss, diarrhea, or observable abnormalities [4,73]. Humans orally inoculated with the parental strain of E. coli O86:B7, E. coli O86, developed increased blood group B Abs [74]. However, E. coli O86:B7 was associated with a gastroenteritis outbreak [75]. ...
Article
Humans and crown catarrhines evolved with the inability to synthesize the oligosaccharide galactose-α-1,3-galactose (α-Gal). In turn, they naturally produce high quantities of the glycan-specific antibodies that can be protective against infectious agents exhibiting the same carbohydrate modification on their surface coat. The protective immunity induced by α-Gal is ensured through an antibody-mediated adaptive and cell-mediated innate immune response. Therefore, the α-Gal antigen represents an attractive and feasible target for developing glycan-based vaccines against multiple diseases. In this review article we provide an insight into our current understanding of the mechanisms involved in the protective immunity to α-Gal and discuss the possibilities and challenges in developing a single-antigen pan-vaccine for prevention and control of parasitic diseases of medical and veterinary concern.
... Human anti-Kdn-glycan antibodies appear during infancy and correlate with the appearance of antibodies against Neu5Gc-glycans. Several antiglycan antibodies in humans that recognize common epitopes such as galactosyl alpha1-3galactose (aGal) or blood group antigens (anti-ABO group) are thought to develop upon immunization by normal microbiome components (58)(59)(60). Antibodies against glycans bearing nonhuman Sia Neu5Gc (48) appear during the first year of life in humans, correlating with dietary introduction of Neu5Gc. ...
Article
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Surface expression of the common vertebrate sialic acid (Sia) N -acetylneuraminic acid (Neu5Ac) by commensal and pathogenic microbes appears structurally to represent “molecular mimicry” of host sialoglycans, facilitating multiple mechanisms of host immune evasion. In contrast, ketodeoxynonulosonic acid (Kdn) is a more ancestral Sia also present in prokaryotic glycoconjugates that are structurally quite distinct from vertebrate sialoglycans. We detected human antibodies against Kdn-terminated glycans, and sialoglycan microarray studies found these anti-Kdn antibodies to be directed against Kdn-sialoglycans structurally similar to those on human cell surface Neu5Ac-sialoglycans. Anti-Kdn-glycan antibodies appear during infancy in a pattern similar to those generated following incorporation of the nonhuman Sia N -glycolylneuraminic acid (Neu5Gc) onto the surface of nontypeable Haemophilus influenzae (NTHi), a human commensal and opportunistic pathogen. NTHi grown in the presence of free Kdn took up and incorporated the Sia into its lipooligosaccharide (LOS). Surface display of the Kdn within NTHi LOS blunted several virulence attributes of the pathogen, including Neu5Ac-mediated resistance to complement and whole blood killing, complement C3 deposition, IgM binding, and engagement of Siglec-9. Upper airway administration of Kdn reduced NTHi infection in human-like Cmah null (Neu5Gc-deficient) mice that express a Neu5Ac-rich sialome. We propose a mechanism for the induction of anti-Kdn antibodies in humans, suggesting that Kdn could be a natural and/or therapeutic “Trojan horse” that impairs colonization and virulence phenotypes of free Neu5Ac-assimilating human pathogens. IMPORTANCE All cells in vertebrates are coated with a dense array of glycans often capped with sugars called sialic acids. Sialic acids have many functions, including serving as a signal for recognition of “self” cells by the immune system, thereby guiding an appropriate immune response against foreign “nonself” and/or damaged cells. Several pathogenic bacteria have evolved mechanisms to cloak themselves with sialic acids and evade immune responses. Here we explore a type of sialic acid called “Kdn” (ketodeoxynonulosonic acid) that has not received much attention in the past and compare and contrast how it interacts with the immune system. Our results show potential for the use of Kdn as a natural intervention against pathogenic bacteria that take up and coat themselves with external sialic acid from the environment.
... In contrast to RBC-induced alloantibody formation, many questions remain regarding the development and regulation of naturally occurring anti-blood group antibodies [1,2]. Several early studies suggested that naturally occurring antibody formation results from the colonization of microbes that express blood group antigens within the first few months of life [29][30][31]. While the ability of blood group-positive microbes to stimulate naturally occurring antibodies provides a mechanism for naturally occurring antibody formation, the factors that regulate immunity to blood group-positive microbes in blood group-positive individuals remains undefined [32]. ...
Article
Over a century ago, Karl Landsteiner discovered that blood group antigens could predict the immunological outcome of red blood cell transfusion. While the discovery of ABO(H) blood group antigens revolutionized transfusion medicine, many questions remain regarding the development and regulation of naturally occurring anti-blood group antibody formation. Early studies suggested that blood group antibodies develop following stimulation by bacteria that express blood group antigens. While this may explain the development of anti-blood group antibodies in blood group-negative individuals, how blood group-positive individuals protect themselves against blood group-positive microbes remained unknown. Recent studies suggest that several members of the galectin family specifically target blood group-positive microbes, thereby providing innate immune protection against blood group antigen-positive microbes regardless of the blood group status of an individual. Importantly, subsequent studies suggest that this unique form of immunity may not be limited to blood group expressing microbes, but may reflect a more generalized form of innate immunity against molecular mimicry. As this form of antimicrobial activity represents a unique and unprecedented form of immunity, we will examine important considerations and methodological approaches that can be used when seeking to ascertain the potential antimicrobial activity of various members of the galectin family.
... Some strains of bacteria were known to express A, B, AB, or O phenotype based on studies conducted by Springer in the 1960s (26). He is famous for his elucidation of the sensitization by A/B antigens expressed in bacteria in the intestinal flora as a possible acquisition of what are called "natural antibodies" (27). In that experiment he demonstrated that chickens grown under sterile conditions did not develop anti-B antibodies, while chickens fed diets contaminated with the O 86 strain of Escherichia coli bacteria that express the B antigen developed anti-B antibodies. ...
Article
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The A and B oligosaccharide antigens of the ABO blood group system are produced from the common precursor, H substance, by enzymatic reactions catalyzed by A and B glycosyltransferases (AT and BT) encoded by functional A and B alleles at the ABO genetic locus, respectively. In 1990, my research team cloned human A, B, and O allelic cDNAs. We then demonstrated this central dogma of ABO and opened a new era of molecular genetics. We identified four amino acid substitutions between AT and BT and inactivating mutations in the O alleles, clarifying the allelic basis of ABO. We became the first to achieve successful ABO genotyping, discriminating between AA and AO genotypes and between BB and BO, which was impossible using immunohematological/serological methods. We also identified mutations in several subgroup alleles and also in the cis-AB and B(A) alleles that specify the expression of the A and B antigens by single alleles. Later, other scientists interested in the ABO system characterized many additional ABO alleles. However, the situation has changed drastically in the last decade, due to rapid advances in next-generation sequencing (NGS) technology, which has allowed the sequencing of several thousand genes and even the entire genome in individual experiments. Genome sequencing has revealed not only the exome but also transcription/translation regulatory elements. RNA sequencing determines which genes and spliced transcripts are expressed. Because more than 500,000 human genomes have been sequenced and deposited in sequence databases, bioinformaticians can retrieve and analyze this data without generating it. Now, in this era of genomics, we can harness the vast sequence information to unravel the molecular mechanisms responsible for important biological phenomena associated with the ABO polymorphism. Two examples are presented in this review: the delineation of the ABO gene evolution in a variety of species and the association of single nucleotide variant (SNV) sites in the ABO gene with diseases and biological parameters through genome-wide association studies (GWAS).
... The identity of the aGal + bacteria targeted by IgA remains elusive but likely includes Gram-negative pathobionts from the Enterobacteriaceae family, as demonstrated for Escherichia (E.) coli O86: B7 (Yilmaz et al., 2014), which expresses the aGal-like glycan Gala1-3Gal(Fuca1-2)b1-3GlcNAcb1-4Glc as part of the lipopolysaccharide (LPS) O-antigen (Guo et al., 2005). Of note, this pathobiont can induce a systemic aGal-specific NAb response in humans (Springer and Horton, 1969) as well as in Ggta1-deleted mice, which is protective against infection by pathogens expressing aGal-like glycans (Yilmaz et al., 2014). The finding that several commensal bacteria in the human gut microbiota express aGal-like glycans (Figure 2-figure supplement 2) suggests that other bacteria might contribute to this protective response. ...
Article
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Genes encoding glycosyltransferases can be under relatively high selection pressure, likely due to the involvement of the glycans synthesized in host-microbe interactions. Here, we used mice as an experimental model system to investigate whether loss of α−1,3-galactosyltransferase gene ( GGTA1 ) function and Galα1-3Galβ1-4GlcNAcβ1-R (αGal) glycan expression affects host-microbiota interactions, as might have occurred during primate evolution. We found that Ggta1 deletion shaped the composition of the gut microbiota. This occurred via an immunoglobulin (Ig)-dependent mechanism, associated with targeting of αGal-expressing bacteria by IgA. Systemic infection with an Ig-shaped microbiota inoculum elicited a less severe form of sepsis compared to infection with non-Ig-shaped microbiota. This suggests that in the absence of host αGal, antibodies can shape the microbiota towards lower pathogenicity. Given the fitness cost imposed by bacterial sepsis, we infer that the observed reduction in microbiota pathogenicity upon Ggta1 deletion in mice may have contributed to increase the frequency of GGTA1 loss-of-function mutations in ancestral primates that gave rise to humans.
... Natural anti-glycan antibodies are relevant soluble components of innate immunity against viral infections, where IgM isotype has a central role but also IgG and IgA are relevant (46,47). Natural anti-glycan IgM antibodies occur in neonates as a response to bacterial colonization, reaching relatively early in life IgM concentration levels similar to those in adults (48). This immune response is addressed to microorganism antigens and autoantigens such as ABO blood groups (A: GalNAcα3(Fucα2)Galβ-; B: ...
Article
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerge during the last months of 2019, expanding throughout the world as a highly transmissible infectious illness designated as COVID-19. Vaccines have now appeared, but the challenges in producing sufficient material and distributing them around the world means that effective treatments to limit infection and improve recovery are still urgently needed. This review is focused on the relevance of different glycobiological molecules that could potentially serve as or inspire therapeutic tools during SARS-CoV-2 infection. As such, we highlight the glycobiology of the SARS-CoV-2 infection process, where glycans on viral proteins and on host glycosaminoglycans have critical roles in efficient infection. We also take notice of the glycan-binding proteins involved in the infective capacity of virus and in human defense. In addition, we critically evaluate the glycobiological contribution of candidate drugs for COVID-19 therapy such as glycans for vaccines, anti-glycan antibodies, recombinant lectins, lectin inhibitors, glycosidase inhibitors, polysaccharides, and numerous glycosides, emphasizing some opportunities to repurpose FDA-approved drugs. For the next generation drugs suggested here, biotechnological engineering making new probes to block the SARS-CoV-2 infection might be based in the essential glycobiological insight on glycosyltransferases, glycans, glycan-binding proteins and glycosidases related to this pathology.
... We have observed this previously, in fact, for individuals infected with various pathogens, including parasitic worms such as Schistosoma mansoni and others 35,53,[81][82][83][84][85][86][87][88][89][90][91][92][93] , as well as in studies on children infected with the protozoan Cryptosporidium parvum 34 , all of whom indicate that specific anti-carbohydrate antibodies are induced only in those individuals infected by specific pathogens. Such studies are also consistent with many historical studies showing that bacterial exposure can lead to specific antibody repertoires in animals 94,95 . ...
Article
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Humoral immunity to pathogens and other environmental challenges is paramount to maintain normal health, and individuals lacking or unable to make antibodies are at risk. Recent studies indicate that many human protective antibodies are against carbohydrate antigens; however, little is known about repertoires and individual variation of anti-carbohydrate antibodies in healthy individuals. Here we analyzed anti-carbohydrate antibody repertoires (ACARs) of 105 healthy individual adult donors, aged 20-60+ from different ethnic backgrounds to explore variations in antibodies, as defined by binding to glycan microarrays and by affinity purification. Using microarrays that contained > 1,000 glycans, including antigens from animal cells and microbes, we profiled the IgG and IgM ACARs from all donors. Each donor expressed many ACAs, but had a relatively unique ACAR, which included unanticipated antibodies to carbohydrate antigens not well studied, such as chitin oligosaccharides, Forssman-related antigens, globo-type antigens, and bacterial glycans. We also saw some expected antibodies to ABO(H) blood group and α-Gal-type antigens, although these also varied among individuals. Analysis suggests differences in ACARs are associated with ethnicity and age. Thus, each individual ACAR is relatively unique, suggesting that individualized information could be useful in precision medicine for predicting and monitoring immune health and resistance to disease.
... Sepsis is propelled by translocation of bacterial pathobionts in the microbiota across host epithelial barriers (Rudd et al., 2020;Vincent et al., 2009). Loss of GGTA1 function allows for targeting of immunogenic bacteria in the microbiota by a-gal-specific NAb (Galili et al., 1988a;Soares and Yilmaz, 2016;Springer and Horton, 1969), suggesting that loss of GGTA1 function might provide some level of protection against bacterial sepsis. While there is no evidence that a-gal-specific NAbs are protective per se against bacterial sepsis, loss of GGTA1 function could exert such a protective effect via other mechanisms. ...
Article
Most mammals express a functional GGTA1 gene encoding the N-acetyllactosaminide α-1,3-galactosyltransferase enzyme, which synthesizes Gal-α1-3Gal-β1-4GlcNAc (α-gal) and are thus tolerant to this self-expressed glycan. Old World primates including humans, however, carry loss-of-function mutations in GGTA1 and lack α-gal. Presumably, fixation of such mutations was propelled by natural selection, favoring the emergence of α-gal-specific immunity, conferring resistance to α-gal-expressing pathogens. Here, we show that loss of Ggta1 function in mice enhances resistance to bacterial sepsis, irrespectively of α-Gal-specific immunity. Rather, the absence of α-gal from IgG-associated glycans increases IgG effector function via a mechanism associated with enhanced IgG-Fc gamma receptor (FcγR) binding. The ensuing survival advantage against sepsis comes alongside a cost of accelerated reproductive senescence in Ggta1-deleted mice. Mathematical modeling of this trade-off suggests that high exposure to virulent pathogens exerts sufficient selective pressure to fix GGTA1 loss-of-function mutations, as likely occurred during the evolution of primates toward humans.
... The origin of the natural anti-ABO antibodies is still debated. Nonetheless, it seems that most of these antibodies appear during the first year of life under stimulation of microorganisms either pathogenic or from the microbiota that carry similar antigens [46,47]. Their amounts are highly variable between individuals and some data suggest that they may decrease with improved hygiene conditions [48,49]. ...
Article
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Since the emergence of COVID-19, many publications have reported associations with ABO blood types. Despite between-study discrepancies, an overall consensus has emerged whereby blood group O appears associated with a lower risk of COVID-19, while non-O blood types appear detrimental. Two major hypotheses may explain these findings: First, natural anti-A and anti-B antibodies could be partially protective against SARS-CoV-2 virions carrying blood group antigens originating from non-O individuals. Second, O individuals are less prone to thrombosis and vascular dysfunction than non-O individuals and therefore could be at a lesser risk in case of severe lung dysfunction. Here, we review the literature on the topic in light of these hypotheses. We find that between-study variation may be explained by differences in study settings and that both mechanisms are likely at play. Moreover, as frequencies of ABO phenotypes are highly variable between populations or geographical areas, the ABO coefficient of variation, rather than the frequency of each individual phenotype is expected to determine impact of the ABO system on virus transmission. Accordingly, the ABO coefficient of variation correlates with COVID-19 prevalence. Overall, despite modest apparent risk differences between ABO subtypes, the ABO blood group system might play a major role in the COVID-19 pandemic when considered at the population level.
... Furthermore, the activation of humoral elements increases platelet adhesion and aggregation, reduces the blood flow in the graft and, consequently, causes graft loss 16 . The existence of natural antibodies (IgM) is believed to be the result of B1 cell stimulation by carbohydrates expressed by gut microbiota, such as levan (generated by enteric bacteria) and peptidoglycan polysaccharide complex (obtained from anaerobic bacteria) shown to be structurally similar to A/B blood antigens 17,18 . Fortunately, the search for anti-donor antibodies through cross-matching has reduced the frequency of hyperacute rejection and increased SOT success rates 19 . ...
Article
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Organ transplantation is considered the main therapeutic approach for the treatment of a wide variety of end-stage diseases. Transplan-tation success rate is dependent on the type of engrafted organs, as well as on the different kinetics of inflammation and immune-mediated responses towards donor antigens during the process. Several environmental factors seem to influence solid organ transplantation (SOT) outcomes, especially the composition of the donor's gut microbiota. Gut microbiota acts as a critical player in the process of matu-ration and modeling of immune responses, modulating not only local but also systemic immune responses. Emerging evidence from animal and human studies have shown that end-stage disease followed by SOT (e.g. kidney , small bowel, liver, lung, and heart trans-plantation) can significantly change gut microbial populations. These changes result in a wide range of outcomes, including intense alloimmune responses, characterized by high frequency of Th1 and Th17 CD4 + T cells. Even though there has been significant progress in the field, it is still important to better characterize the changes in the gut microbiota populations and the mechanisms by which the host immune responses are influenced, which could contribute to additional intervention strategies aimed at improving graft and patient survival. Therefore, this review explores the positive and the negative effects of the gut microbiota in SOT.
Article
Anti-A and anti-B antibodies are naturally occurring and develop from exposure to intestinal bacteria after age 4 to 6 months. In the laboratory, strong agglutination with A1 and B cells, or B cells only and A1 cells only, on reverse typing in a healthy person with immunocompetence is expected for patients with ABO types O, A, and B, respectively. However, absent or weak anti-A and anti-B antibodies can be observed in some clinical scenarios, such as patients with immunodeficiencies, newborns, elderly patients, and patients who have recently received bone marrow transplants. In this article, we report the cases of 2 pediatric patients with group O blood type who were receiving total parenteral nutrition (TPN) and disease-specific enteral feeds and who have strong anti-A and absent/weak anti-B.
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Most mammals express a functional GGTA1 gene encoding the N-acetyllactosaminide α-1,3-galactosyltransferase enzyme, which synthesizes Galα1-3Galβ1-4GlcNAc (αGal) and are thus tolerant to this self-expressed glycan epitope. Old World primates including humans, however, carry GGTA1 loss-of-function mutations and lack αGal. Presumably, fixation of such mutations was propelled by natural selection, favoring the emergence of αGal-specific immunity, which conferred resistance to αGal-expressing pathogens. Here we show that loss of Ggta1 function in mice enhances resistance to bacterial sepsis, irrespectively of αGal-specific immunity. Rather, the absence of αGal from IgG-associated glycans increases IgG effector function, via a mechanism associated with enhanced IgG-Fc gamma receptor (FcγR) binding. The ensuing survival advantage against sepsis comes alongside a cost of earlier onset of reproductive senescence. Mathematical modeling of this trade-off shows that under conditions of high exposure to virulent pathogens, selective pressure can fix GGTA1 loss-of-function mutations, as likely occurred during the evolution of primates towards humans.
Article
Purpose of review: ABO-incompatible (ABOi) heart transplantation (HTx) in young children has evolved from an experimental approach to a standard allocation option in many countries. Clinical and immunological research in ABOi transplantation has revealed insight into the immature immune system and its role in superior graft acceptance in childhood and antigen-specific tolerance. Recent findings: Multicenter experience has confirmed equal actuarial survival, freedom from rejection, and graft vasculopathy comparing ABOi with ABO-compatible HTx. Observations of reduced antibody production and B-cell immunity toward the donor blood group have been confirmed in long-term follow-up. Mechanisms contributing to tolerance in this setting involve the interplay between B-cells and the complement system and the development of B-cell memory. Better characterization of the ABH polysaccharide antigens has improved diagnostic methods and clinical assessment of blood group antibodies. Boundaries regarding age, immune maturity, and therapeutic interventions to extend the applicability of ABOi HTx have been explored and resulted in data that may be useful for HTx patients beyond infancy and ABOi transplantation of other organs. Tolerance of ABH antigens possibly extends to HLA response. Summary: The review provides insight into the clinical evolution of ABOi HTx and associated immunologic discoveries. Current experiences and boundaries are discussed together with recent and potential future developments for utilization in other patient and age groups.
Chapter
The interactions between human and other species have been well documented in anthropology, because human beings are omnivorous. Cooking by boiling can fend off encounters with microbial toxins derived from their growth in foods. For human beings as a self, the most obvious non-self is other species, such as botany and reptiles. (king cobra) can kill humans by its neurotoxin acting on nicotinic acetylcholine receptor (nAchR) in humans [1]. In addition to biting, the ancient ways of transferring molecules to the circulation include inhalation of opium and the arrow poison used by South American Indians to hunt animals, such as curare containing d-tubocurarine that can block nAchR. However, it is needless to say that the most primitive route is per oral administration. Ingested and subsequently absorbed hazardous non-self substances are sensed by the chemoreceptor trigger zone in the midbrain and vomiting reaction takes place to expel the non-self from the self. The principle is that molecules from the non-self can be life-threatening for the self and the biological manifestation includes elimination of non-self or damage of self. The molecular basis is the interaction and subsequent events between a non-self-derived or exogenous molecule and a self-derived or endogenous receptor(s). The responsible sensors are expressed in immune cells, epithelial cells, and neuronal cells.
Chapter
Although the immune system effectively provides protection from foreign pathogens, it creates a major barrier for transplantation. To understand the processes involved in rejection of a transplanted allograft, a fundamental understanding of the immune system and its function in transplant-directed immune responses is required. This chapter reviews the basic immunologic concepts, factors, and mechanisms that contribute to transplant rejection and regulation of alloimmune responses. Key transplantation antigens that can elicit an immune response against the graft are reviewed. The role of adaptive and innate immunity in allograft rejection is described in detail. In addition, potential mechanisms that can regulate alloimmune responses and induce transplant tolerance are discussed. For simplicity, concepts will be explained in the context of solid organ transplantation, where the graft is recognized as foreign and attacked by the host’s immune system. The unique complexities of hematopoietic stem cell transplantation (HSCT) will be discussed separately. This chapter should provide pathologists and clinicians an understanding of basic concepts in transplant-related immunobiology.
Chapter
The interactions between humans and other species have been well documented in anthropology, because human beings are omnivorous. Cooking by boiling can fend off encounters with microbial toxins derived from their growth in foods. For human beings as a self, the most obvious non-self is other species, such as botany and reptiles; king cobra can kill humans by its neurotoxin acting on nicotinic acetylcholine receptor (nAchR) in humans (Rajagopalan et al., FASEB J 21:3685–95, 2007). In addition to biting, the ancient ways of transferring molecules to the circulation include inhalation of opium and the arrow poison used by South American Indians to hunt animals, such as curare containing d-tubocurarine that can block nAchR. However, it is needless to say that the most primitive route is per oral administration. Ingested and subsequently absorbed hazardous non-self substances are sensed by the chemoreceptor trigger zone in the midbrain and a vomiting reaction takes place to expel the non-self from the self. The principle is that molecules from the non-self can be life-threatening for the self and the biological manifestation includes the elimination of non-self or damage of self. The molecular basis is the interaction and subsequent events between a non-self-derived or exogenous molecule and a self-derived or endogenous receptor(s). The responsible sensors are expressed in immune cells, epithelial cells, and neuronal cells.
Chapter
ABH, Secretor, and Lewis SystemsIi Blood Group SystemP Blood Group SystemSummaryDisclaimerReferences
Article
Background: The use of blood group O as "universal blood" for emergency whole blood transfusions carries the risk for a hemolytic transfusion reaction mediated by incompatible A-/B-antibodies. This risk can be minimized by assuring that the donor has a low titer of anti-A and anti-B. The level of these naturally occurring antibodies have been shown to be increased by vaccination with most biologically derived vaccines. This boostering effect has been investigated for the new generation of vaccines. Methods: The 120 crew members of a Swedish naval ship deployed for seven months to the Indian Ocean were tested for anti-A and anti-B before their predeployment vaccination program and after returning to Sweden. The vaccination program contained vaccines against cholera, diphtheria, hepatitis A and B, influenza, measles, meningitis, mumps, pertussis, polio, rubella, TBE-virus, tetanus, typhus and yellow fever. Paired antibody titrations were performed for both IgM and IgG using microtube gelcards (Diamed GMBH). Results: No crew member, including the six belonging to the "high titer" group, showed a sign of a booster effect by any of the used vaccines. Conclusion: The earlier reported boostering effects mediated by different vaccines is not be replicated with the new vaccines of today. This is probably a result of the new manufacturing techniques resulting in much purer vaccines. Level of evidence: Diagnostic test or criteria, level V.
Article
Antibodies specific for the blood group ABO system antigens are of clinical significance and immunological interest. Routine clinical methods typically employ direct or indirect haemagglutination methods to measure IgM and IgG, respectively. We have developed a simple, single tube method to quantify IgM, IgG, and IgA specific for A and B antigens in order to improve accuracy and reproducibility, and to investigate the relationships between ABO group antibody type, and antibody level. Plasma samples from 300 healthy blood donors were studied. Levels of IgM and IgG binding to reagent group A and B red cells were measure by agglutination (HA) and multi-colour flow cytometry (MC-FC). IgA was also measured by MC-FC. Our FC method was found to be significantly more reproducible than HA for the measurement of blood group A and B specific antibodies. We found statistically significant correlations between antibodies measured by GC-HA and MC-FC, but sufficient differences to indicate that these methods are not equivalent. By MC-FC, IgM, IgG and IgA levels and isotope profiles were found to be dependent on both the donor ABO type and the specificity of the antibody. This study demonstrated heterogeneity in the immunoglobulin class profiles of ABO-blood group specific antibodies within the healthy population. Differences in isotype profiles of ABO-blood group specific antibodies may indicate fundamental differences in the immune mechanisms that generate these antibodies. This is likely to be relevant to the clinical situations where management or diagnosis depend on ABO-specific antibody detection and measurement.
Article
Extracellular high-mobility group box 1 (HMGB1) is a prototypic damage-associated molecular pattern. Although a homeostatic level of extracellular HMGB1 may be beneficial for immune defense, tissue repair, and tissue regeneration, excessive HMGB1 is linked to inflammatory diseases. This prompts an intriguing question: how does a healthy body control the level of extracellular HMGB1? In this study, in the plasma of both healthy humans and healthy mice, we have identified an anti-HMGB1 IgM autoantibody that neutralizes extracellular HMGB1 via binding specifically to a 100% conserved epitope, namely HMW4 (HMGB198-112). In mice, this anti-HMW4 IgM is produced by peritoneal B-1 cells, and concomitant triggering of their BCR and TLR4 by extracellular HMGB1 stimulates the production of anti-HMW4 IgM. The ability of extracellular HMGB1 to induce its own neutralizing Ab suggests a feedback loop limiting the level of this damage-associated molecular pattern in a healthy body.
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Genes encoding certain glycosyltransferases are thought to be under relatively high selection pressure, due to the involvement of the glycans that they synthesise in host-microbe interactions. Here we used a mouse model to investigate whether the loss of α-1,3-galactosyltransferase (GGTA1) function and Galα1-3Galα1-4GlcNAcα1-R (αGal) expression during primate evolution might have affected host-microbiota interactions. We found that Ggta1 deletion in mice shaped the composition of the gut microbiota in relation to the bacterial species present. This occurred via an immunoglobulin (Ig)-dependent mechanism, associated with IgA targeting of αGal-expressing bacteria. Systemic infection by the Ig-shaped microbiota elicited a less severe form of sepsis than infection with the non-Ig-shaped microbiota. This suggests that in the absence of host αGal, the microbiota is shaped towards lower pathogenicity, likely providing a fitness gain to the host. We infer that high selection pressure exerted by bacterial sepsis may have contributed to increase frequency of GGTA1 loss-of-function mutations in ancestral primates that gave rise to humans.
Article
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Understanding blood group antigen binding preferences for C-type lectin receptors holds promise for modulating immune responses, since several Gram-negative bacteria express blood group antigens as molecular mimicry to evade immune responses. Herein, we report the synthesis of ABO blood group antigen active tri and disaccharides to investigate the binding specificity with various C-type lectin receptors using glycan microarray. The results of binding preferences show that distinct glycosylation on the galactose and fucose motifs are key for C-type lectin receptor binding and that these interactions occur in a Ca2+-dependent fashion.
Article
The natural anti-Gal antibody constitutes 1% of circulating IgG in humans and interacts specifically with the carbohydrate epitope Gal alpha 1–3Gal beta 1–4GlcNAc-R (the alpha-galactosyl epitope). In view of the unusually large amounts of this antibody in the serum, it was of interest to determine the proportion of circulating B lymphocytes capable of synthesizing anti-Gal. For this purpose, blood B lymphocytes were incubated with Epstein-Barr virus (EBV) and plated in microtiter wells. Proliferation of the EBV transformed B lymphocytes was readily visible after 3 weeks of incubation. The supernatants from wells containing proliferating B-lymphoid clones were assayed for anti-Gal by an agglutination assay with rabbit red blood cells and the specificity of the agglutinating antibodies was further confirmed by their interaction with synthetic oligosaccharides and by enzyme-linked immunosorbent assay with glycoproteins. Approximately 5% of the wells contained anti-Gal antibodies. Limiting dilution studies and IgH gene rearrangement patterns suggested that each well contained an average of five proliferating B-lymphoid clones. Thus, it is concluded that approximately 1% of circulating B lymphocytes are capable of producing anti-Gal. The proportion of anti-Gal--producing lymphoid clones exceeds by fourfold that of clones producing anti-blood group A or anti-blood group B antibodies. Individual anti-Gal clones display fine variations in their combining site, as indicated by their differential interaction with alpha-galactosyl epitopes on glycolipids and on N-linked carbohydrate chains of glycoproteins. The high frequency of precursor B lymphocytes capable of producing anti-Gal, found in every individual and the restricted specificity of this antibody to alpha-galactosyl epitopes, potentially makes anti-Gal--producing lymphocytes an effective system for studying human Ig genes involved in the natural immune response to structurally defined haptens.
Article
The generation of ABO hemagglutinins was used as a model to assess the tempo of reconstitution of antibody responses in recipients of elutriated (CCE) and nonelutriated (nonCCE) HLA matched bone marrow allografts. The study included 29 CCE recipients (10 major, 6 minor, and 1 major/minor ABO-mismatched, and 12 ABO-matched) and 40 nonCCE recipients (14 major, 12 minor, 2 major/minor, and 12 matched). Plasma volume in the graft and in blood product transfusions was uncorrelated with changes in hemagglutinin titers and therefore was excluded as a significant source of antibody. Removal of graft lymphocytes by CCE did not result in prolongation of host-derived hemagglutinins in recipients of major ABO-mismatched grafts. However, CCE resulted in a complete abrogation of the adoptive transfer of donor-derived antibody as detected in recipients of minor ABO-mismatched grafts. Despite the absence of adoptively transferred donor immunity in recipients of CCE grafts, they had hemagglutinin levels comparable with those of recipients of nonCCE grafts by 6 months after transplantation. This demonstrates that recipients of elutriated marrow were competent to mount de novo responses at that time. The strong correlation between donor pretransplant hemagglutinin titer and recipient titer 1 year after bone marrow transplantation in recipients of nonCCE grafts suggests that even late after transplant, antibody remains the product of adoptively transferred memory cells in recipients of grafts containing large numbers of mature lymphocytes.
Article
Background Rituximab (RIT) is effective as a part of the desensitization therapy before ABO-incompatible kidney transplantation (ABOi-KTx), and a single dose of RIT at 375 mg/m² or less is recommended. However, adequate RIT dose recommendations have not yet been established for individual recipients. Therefore, we evaluated the relationship between the proportion of B cells in peripheral blood and acute antibody-mediated rejection (AAMR). Methods Forty-four consecutive ABOi-KTx recipients were enrolled in this retrospective study. Before transplantation, subjects were treated with RIT at various doses, ranging from 65 to 400 mg/body (46–263 mg/m²), followed by plasmapheresis and intravenous immunoglobulin as a desensitization therapy. The percentage of CD19⁺ cells in the total peripheral blood lymphocytes population (%CD19) was determined the day before transplantation. Transplant recipients were divided into 2 groups according to pretransplant %CD19, as follows: low %CD19 group, ≤ 1.2% (n = 35) and high %CD19 group, > 1.2% (n = 9). The relationship between %CD19 and incidence of AAMR was evaluated, and the predicting factors for AAMR incidence were determined by univariate and multivariate analyses. Results The incidence of AAMR was significantly higher in the high %CD19 group than in the low %CD19 group (44.4% vs 5.7%, P = .006). Furthermore, multivariate analysis showed that %CD19 > 1.2% was the only independent factor to predict AAMR, with an odds ratio of 14.31 (P = .038). Conclusion High %CD19 values after rituximab administration in ABOi-KTx recipients implies insufficient depletion of B cells, which can lead to AAMR.
Chapter
Anti-carbohydrate antibody responses play a critical role in transplantation and can lead to hyperacute rejection. Pre-existing antibody responses to ABO blood group carbohydrate antigens present a major impediment to ABO-incompatible blood transfusions and organ transplantation. These antibodies are thought to arise as the result of exposure to similar epitopes found on gut microbiota. Several strategies exist for minimizing the effect of these antibodies for ABO-incompatible organ transplantation. Work is also progressing towards the efficient removal of these carbohydrates on red blood cells for use in blood transfusion and transplantation settings. Carbohydrate antigens such as αGal and Neu5Gc present major barriers to xenotransplantation, with antibodies against these antigens causing antibody-mediated rejection. Current work is aimed towards eliminating these antigens in genetically engineered pigs in the hope that successful xenotransplantation will help alleviate the shortage of compatible donor organs. Serum anti-carbohydrate antibodies against both ABO and αGal are also involved in other disease processes. Anti-αGal IgE responses are implicated in red meat allergy following exposure to αGal from tick bites. Anti-ABO and anti-αGal responses can also be protective against infectious disease. This chapter discusses the role of serum anti-carbohydrate antibodies in blood transfusion, organ transplantation, xenotransplantation, allergy and infectious disease.
Chapter
It is now generally agreed that the hyperacute rejection (HAR) of pig organs by both human and nonhuman primates is related to the presence of preformed “natural” antibodies in the host [1–4]. The true origin of these antibodies is speculative, but they develop within a few weeks after birth, probably as soon as the neonate’s gastrointestinal tract becomes colonized by microorganisms [5, 6]. The antibody-antigen reaction that takes place on the surface of the vascular endothelium stimulates the complement cascade and “activates” the endothelial cells [7], leading to endothelial cell damage with capillary disruption and interstitial hemorrhage [8], resulting in rapid destruction of the tissues with loss of function.
Article
Nondialyzable substances capable of inhibiting anti-A, anti-B and anti-H(O) specific blood-group agglutinins have been found in higher and lower plants. In higher plants, they were encountered almost regularly and nearly exclusively in the Gymnospermae. Partial purification showed the active principle to be in the carbohydrate fraction and practically free of nitrogen. Bacteria grown on completely synthetic media usually contained the most potent material in their somatic carbohydrate antigens but often were found to be active as such. Specific action was exhibited by Taxus twig extracts, the purest fraction of which was considerably more active against eel anti-H(O) serum than any known mammalian blood-group mucoid. Escherichia coli 086 exhibited high and E. coli 026 moderate B activity exclusively and Salmonella poona and S. atlanta neutralized eel anti-H(O) serum only while a strain of Escherichia freundii inhibited anti-A sera only. Many other preparations were less specific and neutralized antibodies against blood group A, B and H(O). The exact mode of action of these latter substances will have to be established individually. Several of these serologic blood-group active materials, some of them essentially physicochemically homogeneous, possess other biologic activities as well. There is indication that at least those substances from plants which are disproportional in their action bear an immunologic relationship to mammalian blood-groups mucoids. The possible significance of these findings especially for the problem of “natural iso-antibodies” has been mentioned.
Article
Substances with blood-group ABH(0) specificity are not confined to human red blood cells. Rather, such substances are ubiquitous antigenic surface structures which Nature has preserved throughout the phylogenetic development from microbes to man. — It could be shown experimentally that so-called “pre-existing natural” antibodies can result from inapparent immunization by these widely distributed antigens. — The blood-group specific structures of bacteria are chemically closely related to the determinant structures of the human blood-group ABH(0) glycoproteins. The situation is more complicated for the blood-group active substances from higher plants; these give extraordinary immunochemical reactions and two of their blood-group specific monosaccharides precipitate antibodies. — Recently the nature of the M and N blood-group antigens of erythrocyte surfaces has been elucidated. They are the main antigens of the second of at least 14 human blood-group systems. These substances, which are glycoproteins, are also excellent myxovirus receptors and inhibitors. The NN antigen is the first reported physically homogeneous, chemically defined and highly blood-group active cell surface structure of human origin. As surface structures, blood-group active substances appear to be frequently endowed with receptor properties in addition to those for blood-group antibodies.
Article
Distribution of blood group A, B, and H(O) activities among 282 aerobic Gram-negative bacteria, many isolated from the blood of patients, has been studied. Almost half of these bacteria were found to be blood group active. About 10 per cent of the organisms exhibited high, disproportional activities, which in some instances approached those of crude human blood group mucoids. No significant, specific D (Rho), M, or N activity was found in approximately 70 members of the Enterobacteriaceae. An attempt was made to correlate the observed activity of a given organism of known O somatic antigen with its monosaccharide components. The presence of those sugars which account for the specificity of human blood group mucoids was noted. The bearing of these findings on the origin of human anti-A and anti-B isoantibodies has been mentioned.
Article
The chapter focuses on the developmental aspects of immunity. The ontogenetic development of immune responses in the immature animal and the developmental cellular stages of the immune response in the adult animal are discussed in this chapter. The cellular mechanisms underlying the several immune responses have not received the full attention either to the evolutionary principles underlying the development of all biological systems or to the broad biological rules that govern the proliferative and differentiate activities of cells in any biologically functioning system. The chapter reviews the immunological status of fetal and neonatal mammals as well as several aspects of the ontogeny of the immune response when examined by the most sensitive technique presently available. Developmental stages of immune reactions and their mutual relationships such as relationship of phagocytosis to specific cellular reactions, relationship of delayed hypersensitivity to antibody formation, and dynamics of antibody formation are also presented in this chapter. The increase of immunological capacity with age and the appearance of natural antibodies result solely from specific antigenic stimulation; the chapter discusses the Unitarian concept of cell differentiation and proliferation underlying any form of immunological response. Several methods for studying developmental aspects of immunity and immunological development are also discussed in this chapter.
Article
NATURALLY occurring antibodies to antigens of erythro-cytes, tissues such as liver, and microbes are invariably detectable in the serum of fully grown animals but are not found in the serum of the new-born. Whether these antibodies arise as a result of normal physiological maturation or as a result of inapparent immunization has puzzled immunologists for many years. There is evidence that the blood group and microbial antibodies may be formed as a response to ingested antigens, since their production has been prevented in some cases by rearing the animals in a germ-free environment. Germ-free chicks, for example, promptly developed antibodies to blood group B antigen after the oral administration of Escherichia coli 086, an organism with blood group B antigenic determinants1. The phenomenon of naturally occurring complement-fixing serum substances reactive with extracts of mammalian tissue, including an animal's own tissue, is not readily explained2,3. It is possible that these substances, which are serum globulins, are not antibodies formed in response to antigenic stimulation. When combined with tissue for which they have an affinity, they may conceivably be aggregated and thereby fix complement4.
Article
The normal antibodies of human sera that are capable of reacting with human B, but not O, red blood cells, are heterogeneous in kind and degree of specificity. These antibody populations are fractionable by absorption with red cells of various animals. Sera from different individuals of group A, for example, contain different relative activities of a β-antibody fraction that will crossreact with opossum red cells and one that will not so cross-react. In certain group O sera, most of the “β antibody” fraction that is not cross-reactive with opossum red cells proves to be absorbable by (and therefore cross-reactive with) human A cells. Inhibition with opossum saliva has effects closely comparable to absorption with opossum red cells. Other fractionations and tests have been performed, using red cells of man, rabbits, guinea pigs, hamsters, cotton rats, Norway rats, chickens, sheep and cattle, singly and in various combinations. In addition to a considerable diversity of normal antibody specificities within particular sera, there are marked differences among the sera of individuals of the same classical blood group, as well as among the different blood groups. Immune sera produced by injecting rabbits with human red cells also display antibody populations with diverse patterns of specificity and cross-reactions. Antibody fractions from different sources, cross-reactive with A and B (but not O) human cells, are not all alike; they vary in other details of their specificities, and are often subfractionable by absorption with related antigens. Experimental data upon which the hypothesis of linkage between specific α and β antibodies has been based are reinterpreted in terms of the heterogeneous antibody populations demonstrated in this study. Fractionation of sera by absorption with animal cells offers promise as a source of reagents for details of antigenic variation in human cells otherwise difficult or impossible to detect. For example, reagents for a pattern of reactivity common to A, B, and certain rare “O” antigens may be obtainable by absorbing selected O sera with particular animal cells. The problem of removing all of the specific α antibodies, but leaving the cross-reactive antibodies, has however not been solved. Other implications of the observations reported in this paper, relevant to the origins and behavior of the normal antibodies, have been discussed.
Article
1. Anti-A and anti-B sera from individuals immunized with various blood group substances and by heterospecific pregnancy have been examined by the Coombs test in block titration and by Coombs test after neutralization by blood group substances and found to fall into two groups, one showing enhancement in Coombs titer over the saline agglutinin titer and the other failing to show such enhancement. 2. The results indicate that no proper distinction can be made between such antibodies on the basis of their being “natural” or immune.
Article
While anti-human blood group B agglutinins are present in the majority of ordinary White Leghorn chicks by the age of 30 days, none could be demonstrated in germfree chicks up to the age of 60 days. Anti-B agglutinins in trace amounts were first found in germfree chicks 66 days old and increased to an average titer of about 1:2 by 91 days of age. This titer amounts to about 10 per cent of that found in ordinary chicks. The appearance of antibody in low titer is attributed to trace amounts of non-living antigenic contaminants penetrating the germfree barrier. The necessity of appropriate absorption in order to obtain well defined specificities was pointed out. Several means commonly used to differentiate between normal and immune antibodies were employed in this investigation. None showed a difference between anti-B agglutinins from ordinary chicks and from germfree chicks intentionally immunized with blood group B active E. coli O86 or with B active preparations from human meconium. The implications of these findings on the origin of natural agglutinins are discussed. It is concluded, that measurable anti-human blood group B agglutinins in White Leghorn chicks are acquired early in life and are not inherited. The possibilities as well as limitations of present day germfree technique for this kind of immunological research have been considered.
Article
Human and chicken erythrocytes are readily coated in vitro by blood group active protein-lipopolysaccharides and lipopolysaccharides from E. coli O(86) and E. coli O(128). Serum albumin, alpha(2)- and beta-lipoproteins inhibit this sensitization. Blood group B specific agglutination of erythrocytes with B or B-like antigens was obtained with antibodies purified by adsorption on and elution from B erythrocytes. Anti-blood group B and E. coli O(86)-specific antibodies could be eluted from E. coli O(86)-coated O erythrocytes. Eel anti-H(O) serum agglutinated O erythrocytes and only those A(1)B red cells which were coated with blood group H(O) active E. coli products. Blood group active substances specifically inhibited agglutination of lipopolysaccharide-coated erythrocytes by anti-B and anti-H(O) agglutinins. Demonstrable amounts of lipopolysaccharide could only be removed from coated erythrocytes by washing them at elevated temperatures (58 degrees C) in physiological solutions. Red cell sensitization with B active E. coli O(86) substances was achieved in vivo in a minority of severely diseased infants and in germ-free and ordinary chicks which were in tourniquet shock after treatment with cathartics. Therefore, a possible mode by which erythrocytes of patients with severe intestinal disorders acquire antigens is the fixation of bacterial substances to their surfaces, if there are not enough of the normally interfering plasma factors present.
Article
L-Fucopyranose in α-glycosidic linkage has been thought to be responsible for blood-group-H(O) specificity of human blood-group mucoids as determined with heterologous anti-H(O) reagents from the eel and Lotus tetragonolobus. This conclusion was based on hapten studies. However, some L- and D-fucose-O-methyl ethers were as active as L-fucose. Therefore the stereo-specific requirements for the activities of fucose methyl ethers and their methylglycosides were systematically investigated. Eight fucose-O-methyl ethers and fourteen methylglycopyranosides of fucose were synthesized and characterized. The majority of these sugars were crystallized and ten are novel. Quantitative precipitin-inhibition tests in the eel serum anti-H(O)-H(O) substance system were only in qualitative accord with hemagglutination-inhibition tests. A number of methylated L- and D-fucoses and their methylglycopyranosides were potent inhibitors. The enantiomorphs of 3-O- and 2,3-di-O-methylfucoses had nearly identical activities. 3-O-Methylfucose precipitated the anti-H(O) antibody of some eel sera and may thus be the smallest uncharged antibody-precipitating hapten yet found. The complementary structure for the eel serum antibody is probably smaller than a monosaccharide. It seems to consist of a methyl substituent attached equatorially to a pyranose; there is an ether oxygen adjoining the methyl and an axial, oxygen-carrying substituent cis to the methyl group is on a contiguous C atom. An O-methyl at C-4 is compatible with activity. Hapten requirements for activity in the Lotus system differ; a substituent at C-2 is a precondition in the D series. A furanoid structure substituted with three O-methyl groups is equally active in both series. While appropriate methyl substitution increases the activity of highly active fucose compounds, it can inactivate slightly active fucose ethers.
Article
Subcutaneous injection of non-dialyzable preparations from commercial chicken egg-grown influenza virus vaccines, corresponding in amount to 3 or more protective doses, and from highly purified egg-grown influenza virus stimulate the production of powerful isoagglutinins with anti-A and cross-reacting anti-B specificity in the majority of humans. Potent isohemolysins are also produced. The relation of these antibodies to cytotoxic Forssman antibodies is considered. L'injection sous-cutanée de préparations non-dialysables de vaccine commerciaux du virus de l'influenza cultivé sur œufs de poulet, quantité correspondant à 3 doses protectives ou plus, et de vaccins du virus de l'influenza cultivé sur œufs de poulet hautement purifiés stimule la production de puissantes iso-agglutinines avec la spécificité anti-A et la réactivité croisée anti-B chez la majorité des hommes. De puissantes iso-hémolysines sont également produites. Le rapport entre la présence de ces anticorps et les anticorps du type Forssman cytotoxiques est discuté. Die subkutane Injektion nicht-dialysierbarer Präparationen kommerzieller, auf Hühnereiern gezüchteter Influenza-Virus-Vakzinen, entsprechend der Menge von 3 oder mehr Schutzdosen, sowie von gereinigtem, auf Hühnereiern gezüchtetem Influenza-Virus, bewirkt bei der Mehrzahl der Menschen die Bildung hochaktiver Anti-A- und kreuzreagierender Anti-B-Isoagglutinine. Im weiteren werden kräftige Isohämolysine gebildet. Die Beziehung dieser Antikürper zu den zytotoxischen Forssman-Antikürpern wird diskutiert.
Article
Evidence relating to the problem of the origin of natural antibodies, especially hemagglutinins and hemolysins has been critically reviewed. Based on this analysis it is concluded that natural antibodies are, with possibly rare exceptions, of immune origin. Natural antibodies, like those generally conceded to be of immune origin such as Rh antibodies, occur in the univalent as well as the bivalent form. Natural immunity to bacteria and viruses is generally conceded to be due to undiagnosed or symptomless infections, since such immunity is most frequent among individuals who have been exposed to the disease or who carry the microörganism in their body. The peristence of natural antibodies throughout life is explained by experiments on Rh sensitization showing that antibodies induced by deliberate immunization likewise may persist indefinitely after all contact with the antigen has been discontinued. Natural antibodies for red cells, such as the blood group antibodies and cold hemagglutinins, are shown to be of heterogenetic immune origin and are attributable to the presence of related antigens in bacteria and animal parasites. Polysaccharides of similar chemical structure have been isolated from capsules of penumococci as well as from secretions possessing blood group specificity, thus providing a chemical explanation for such heterogenetic reactions.
Heredity of blood groups: 197. 16. Hirszfeld, L. 1926. t~ber die Konstitutionsserologie im Zusammenhang mit der Blutgruppenforschung
  • T Furuhata
Furuhata, T. 1927. Heredity of blood groups. Jap. Med. World. 7: 197. 16. Hirszfeld, L. 1926. t~ber die Konstitutionsserologie im Zusammenhang mit der Blutgruppenforschung. Ergeb. Hyg. 8: 367.
Zur Kenntnis der Bildung der Normalantikorper. Ungleiche Isoagglutininwerte bei eineiigen Drillengen
  • F Ottensooser
  • W Tobler
Ottensooser, F., and W. Tobler. 1937. Zur Kenntnis der Bildung der Normalantikorper. Ungleiche Isoagglutininwerte bei eineiigen Drillengen. Z. Immunitaetsforsch. Allergie Klin. Immunol. 90: 65.
Contribution a l'etude des antigenes des globules rouges
  • M Dupont
Dupont, M. 1934. Contribution a l'etude des antigenes des globules rouges. Arch. Int. Med. Exp. 9: 133.
Relationship between somatic antigen and blood group substance, especially B substance, of bacterium
  • S Iseki
  • E Onuki
  • K Kashiwagi
Iseki, S., E. Onuki, and K. Kashiwagi. 1958. Relationship between somatic antigen and blood group substance, especially B substance, of bacterium. Gut&ma J. Med. Sci. 7: 7.
Normal and immune hemagglutinins of domestic fowl with respect to their origin, specificity and identity VUber blutgruppen-spezifische Antikorper und Antigene
  • C E Bailey
Bailey, C. E. 1923. Normal and immune hemagglutinins of domestic fowl with respect to their origin, specificity and identity. Amer. J. Hyg. 3: 370. 25. Schiff, F., and L. Adelsberger. 1924. VUber blutgruppen-spezifische Antikorper und Antigene. Cent. Bakteriol. Parasitol. 93: 172.
tber die Entstehung der ABO-Isoantikorper beim Saugling
  • W Korner
  • W Maassen
  • H J Pettenkofer
Korner, W., W. Maassen, and H. J. Pettenkofer. 1962. tber die Entstehung der ABO-Isoantikorper beim Saugling. Z. Immunitaetsforsch. Allergie Klin. Immunol. 123: 473.
Appearance of natural antibodies in young rabbits Horton's contribution to this paper was confined to rearing, injecting, and bleeding chickens, as well as evaluating the manuscript. This statement is inserted at the request of Dr. Horton's superiors
  • W A Hook
  • A F Toussaint
  • L A Simonton
  • L H Muschel
Hook, W. A., A. F. Toussaint, L. A. Simonton, and L. H. Muschel. 1966. Appearance of natural antibodies in young rabbits. Nature (London). 210: 543. Dr. R. E. Horton's contribution to this paper was confined to rearing, injecting, and bleeding chickens, as well as evaluating the manuscript. This statement is inserted at the request of Dr. Horton's superiors. Blood Group Isoantibody Stimulition by Microbes 12 1291
Antigengemeinschaften zwischen gruppen und Enterobacteriaceen
  • H J Pettenkofer
  • W Maassen
  • R Bickerich
Pettenkofer, H. J., W. Maassen, and R. Bickerich. 1960. Antigengemeinschaften zwischen gruppen und Enterobacteriaceen. Allergie Klin. Immunol. 119: 415