[show abstract][hide abstract] ABSTRACT: The killer cell immunoglobulin-like receptor (KIR)-human leukocyte antigen (HLA) interaction represents an example of genetic epistasis, where the concomitant presence of specific genes or alleles encoding receptor-ligand units is necessary for the activity of natural killer (NK) cells. Although KIR and HLA genes segregate independently, they co-evolved under environmental pressures to maintain particular KIR-HLA functional blocks for species survival. We investigated, in 270 Italian healthy individuals, the distribution of KIR and HLA polymorphisms in three climatic areas (from cold north to warm south), to verify their possible geographical stratification. We analyzed the presence of 13 KIR genes and genotyped KIR ligands belonging to HLA class I: HLA-C, HLA-B and HLA-A. We did not observe any genetic stratification for KIR genes and HLA-C ligands in Italy. By contrast, in a north-to-south direction, we found a decreasing trend for the HLA-A3 and HLA-A11 ligands (P = 0.012) and an increasing trend for the HLA-B ligands carrying the Bw4 epitope (P = 0.0003) and the Bw4 Ile80 epitope (P = 0.0005). The HLA-A and HLA-B KIR ligands were in negative linkage disequilibrium (correlation coefficient -0.1211), possibly as a consequence of their similar function in inhibiting NK cells. The distribution of the KIR-HLA functional blocks was different along Italy, as we observed a north-to-south ascending trend for KIR3DL1, when coupled with HLA-B Bw4 ligands (P = 0.0067) and with HLA-B Bw4 Ile80 (P = 0.0027), and a descending trend for KIR3DL2 when coupled with HLA-A3 and HLA-A11 ligands (P = 0.0044). Overall, people from South Italy preferentially use the KIR3DL1-HLA-B Bw4 functional unit, while those from the North Italy equally use both the KIR3DL2-HLA-A3/A11 and the KIR3DL1-HLA-B Bw4 functional units to fight infections. Thus, only KIR3DL receptors, which exert the unique role of microbial sensors through the specific D0 domain, and their cognate HLA-A and HLA-B ligands are selectively pressured in Italy according to geographical north-to-south distribution.
[show abstract][hide abstract] ABSTRACT: Mycosis fungoides (MF) is the most common and one of the least aggressive forms of cutaneous T-cell lymphoma. Several studies have demonstrated the influence of human leucocyte antigen (HLA) genes on the susceptibility of MF, highlighting the importance of certain alleles but, until today, no studies have evaluated the relationship between HLA alleles and the prognosis of patients with MF.
The aim of this retrospective cohort study was to evaluate the polymorphism of HLA class I and class II alleles in a group of 46 MF Caucasian patients, looking for their influence in susceptibility and prognosis of the disease.
Study population included a case-cohort sample of 46 Caucasian patients with MF that, between 1993 and 1997, underwent HLA class I and II genomic typing. All patients were diagnosed and followed up from 1977 to 2012 (mean follow-up of 11 years) and they were divided into three groups according to the evolution of the disease.
Molecular typing at low-resolution level revealed that HLA-A*24, A*68, A*69, B*35 and DQB1*05:02 alleles were involved in susceptibility to MF. Correspondence analysis underlined that long-lasting remission was characterized by HLA-A*24 and HLA-A*25 alleles, frequent relapse by HLA-DRB1*01, DQA1*01:01, DQB1*05:01 alleles and death by HLA-A*68, HLA-B*08, HLA-B*35, HLA-C*03 alleles.
This study suggests that the prognosis of MF patients is not only correlated with clinical/pathological/serological/immunological variables but it also relies on specific HLA alleles.
Journal of the European Academy of Dermatology and Venereology 02/2014; · 2.69 Impact Factor
[show abstract][hide abstract] ABSTRACT: The effect of minor H antigen mismatching on the occurrence of GvHD and GvL after HLA-matched hematopoietic stem-cell transplantation (HSCT) has mainly been demonstrated in single center studies. Yet, the International Histocompatibility and Immunogenetics Workshops (IHIWS) provide a collaborative platform to execute crucial large studies. In collaboration with 20 laboratories of the IHIWS, the role of 10 autosomal and 10 Y-chromosome encoded minor H antigens was investigated on GvHD and relapse incidence in 639 HLA-identical related donor (IRD) and 210 HLA-matched unrelated donor (MUD) HSCT. Donor and recipient DNA samples were genotyped for the minor H antigens HA-1, HA-2, HA-3, HA-8, HB-1, ACC-1, ACC-2, SP110, PANE1, UGT2B17, and HY. The correlations with the primary outcomes GvHD (acute or chronic GvHD), survival, and relapse were statistically analyzed. The results of these multi-center analyses show that none of the HLA class I-restricted HY antigens were found to be associated with any of the primary outcomes. Interestingly, of the HLA class II-restricted HY antigens analyzed, HLA-DQ5 positive recipients showed a significantly increased GvHD-free survival in female-to-male HSCT compared to male-to-female HSCT (p=0.013) in HLA-DQ5-positive recipients. Yet, analysis of the overall gender effect, thus independent of the known HY antigens, between the gender groups demonstrated an increased GvHD incidence in the female to male transplants (p<0.005) and a decreased GvHD free survival in the female to male transplants (p<0.001). Of all autosomally encoded minor H antigens, only mismatching for the broadly expressed minor H antigen HA-8 increased the GvHD incidence in IRD HSCT (Hazard Ration (HR)=5.28; p<0.005), but not in MUD HSCT. Most striking was the influence of hematopoietic restricted minor H antigens on GvL as mismatching for hematopoietic minor H antigens correlated with lower relapse rates (p=0.078), higher relapse free survival (p=0.029) and higher overall survival (p=0.032) in recipients with GvHD, but not in those without GvHD. In conclusion, the significant GvHD effect of the broadly expressed minor H antigen HA-8 favors matching for HA-8 in IRD, but not in MUD, patient/donor pairs. The GvHD-GvL association demonstrating a significant lower relapse in hematopoietic minor H antigen mismatched patient/donor pairs underlines their clinical applicability for adoptive immunotherapy enhancing the GvL effect in a GvHD controllable manner.
Biology of blood and marrow transplantation: journal of the American Society for Blood and Marrow Transplantation 06/2013; · 3.15 Impact Factor
[show abstract][hide abstract] ABSTRACT: BACKGROUND: Cord blood provides haematopoietic stem cells for allogeneic transplantation and, thanks to the naivety of its immune system, has several advantages over other sources of stem cells. In the transplantation setting, the presence of immunosuppressive human leucocyte antigen (HLA)-G molecules has been advocated to prevent both rejection and Graft-versus-Host disease. HLA-G is physiologically expressed throughout pregnancy and is contained in cord blood at birth. Moreover, it has recently been reported that not only cord blood mesenchymal cells, but also CD34(+) cell progenies produce soluble HLA-G (sHLA-G). We tried to identify the largest producer of sHLA-G among 85 healthy cord blood donors at Pavia Cord Blood Bank, correlating the sHLA-G concentration with the HLA-G 14bp insertion/deletion (INS/DEL) genotype and CD34(+) cell concentration. MATERIALS AND METHODS: We measured sHLA-G levels in 36 cord blood plasma stored at 20 °C for 2 months and 49 cord blood plasma stored at 196 °C for 4-6 years, by enzyme-linked immunosorbent assay. All cord blood donors were genotyped for the HLA-G 14bp INS/DEL polymorphism by polymerase chain reaction. For each cord blood unit, we measured the cell concentration by flow cytometry. RESULTS: We did not find differences in sHLA-G levels between cord blood plasma aliquots stored for 4-6 years at 196 °C and cord blood plasma aliquots stored for 2 months at 20 °C. We observed a higher sHLA-G concentration in cord blood plasma donors who carried the HLA-G 14bp INS/INS genotype and had higher CD34(+) cell concentrations (P =0.006). DISCUSSION: This is the first report showing that the best cord blood stem cell donor is also the best sHLA-G producer, particularly if genetically characterized by the HLA-G 14bp INS/INS genotype. If the therapeutic role of sHLA-G molecules were to be finally established in the transplantation setting, our data suggest that cord blood plasma donors can provide a safe source of allogeneic sHLA-G immunosuppressive molecules ready for transfusion.
[show abstract][hide abstract] ABSTRACT: We compared the immunogenetic data from 2666 patients affected by HLA-related autoimmune diseases with those from 4389 ethnically matched controls (3157 cord blood donors CBD, 1232 adult bone marrow donors BMD), to verify the appropriateness of HLA typing requests received in the past decade. The frequency of HLA-B∗27 phenotype was 10.50% in 724 ankylosing spondylitis, 16.80% in 125 uveitis (3.41% BMD, 4.24% CBD, P < 0.0001); HLA-B∗51 allele was 15.57% in 212 Behçet's disease (12.91% BMD, 9.88% CBD, P < 0.0001); the HLA-DRB1-rheumatoid arthritis (RA) shared epitope was 13.72% in 554 RA (10.85% BMD, 13.48% CBD, P = 0.016); the carriers of almost one of HLA-DQB1 susceptibility alleles were 84.91% in 795 celiac disease (CD) and 59.37% in 256 insulin-dependent diabetes mellitus (IDDM) (46.06% in 875 CBD, 42.75% in 662 BMD P < 0.0001). Overall, our results show that the HLA marker frequencies were higher in patients than controls, but lower than expected from the literature data (excluding CD and IDDM) and demonstrate that, in complex immunogenetic conditions, a substantial number of genetic analyses are redundant and inappropriate, burdening to the public health costs. For this reason, we suggest the Italian Scientific Society of Immunogenetics to establish guidelines to improve the appropriateness of typing requests.
BioMed research international. 01/2013; 2013:904247.
[show abstract][hide abstract] ABSTRACT: Whipple's disease (WD) is a very rare chronic systemic condition characterised by a Th2/T regulatory (Treg) dysregulated immune response versus Tropheryma whipplei, a bacterium widely diffuse in the environment. To investigate whether this Th2/Treg polarised response has a genetic background, we investigated the Th1, Th2, Th17 and Treg cytokine genetic profile of 133 patients with WD. Thanks to the European Consortium on WD (QLG1-CT-2002-01049), the polymorphism of 13 cytokine genes was analysed in 111 German and 22 Italian patients using the polymerase chain reaction with sequence-specific primers (PCR-SSP) technique. The frequencies of the genotypes, haplotypes and functional phenotypes were compared with those obtained in 201 German and 140 Italian controls. Clinical heterogeneity was also considered. Functionally, WD patients may be considered as low producers of TGF-β1, having an increased frequency of the genotype TGF-β1+869C/C,+915C/C [12.3 % vs. 3.81 %, odds ratio (OR) = 4.131, p = 0.0002] and high secretors of IL-4, carrying the genotype IL-4-590T/T (5.34 % vs. 1.17 %, OR = 5.09, p = 0.0096). No significant association was found between cytokine polymorphism and clinical variability. Analogously to the recent cellular findings of a Th2/Treg polarised response, we showed that the cytokine genetic profile of WD patients is skewed toward a Th2 and Treg response. This was similar in both German and Italian populations. However, the significant deviations versus the controls are poorer than that expected on the basis of these recent cellular findings.
European Journal of Clinical Microbiology 07/2012; 31(11):3145-50. · 3.02 Impact Factor
[show abstract][hide abstract] ABSTRACT: Type 1 diabetes mellitus (T1DM), celiac disease (CD) and autoimmune thyroid disease (ATD) are autoimmune conditions relatively common in paediatric age and frequently occur in association in the same subject. This event is not by chance and requires an explanation. Here, we studied the distribution of HLA-DQ αβ heterodimers in 334 Italian children with T1DM, ATD and CD alone or in association and in 224 Italian healthy controls. In particular, 164 patients had T1DM (133 alone, 20+ATD, 7+CD and 4+CD+ATD), 118 had ATD (110 alone, 8+CD) and 52 had CD (40 alone, 11+ATD and 1+T1DM). 51 patients suffered from multiple autoimmune diseases. The risk for multiple autoimmune diseases was significantly associated with the increased number of HLA-DQ markers of susceptibility for both T1DM (p = 0.003) and CD (p = 0.006). The presence of one or more diabetogenic DQ molecules significantly increased the probability of developing not only T1DM (p < 0.001) but also CD (p < 0.001) and ATD (p = 0.001). Similarly, the presence of one or more celiac HLA-DQ heterodimers significantly increased the likelihood of developing not only CD (p < 0.001), but also T1DM (p < 0.001) and ATD (p < 0.001). We confirm that the sharing of the immunogenetic background is responsible for the development of multiple autoimmune diseases although with a different risk according to the number and type of susceptible HLA-DQ heterodimers as reported in the algorithm proposed here. It is likely that combinations of DQA1 and DQB1 alleles are the real culprits of the progression towards multiple autoimmune diseases and HLA-DQ genomic typing will improve the capability to predict associated autoimmune diseases in infancy.
[show abstract][hide abstract] ABSTRACT: The HLA genomic structure underlines the permanence of fixed haplotypes transmitted in blocks as allelic combinations. One of the most discussed concerns is how and why such a strong linkage between HLA alleles has been maintained for so long. We hypothesized a possible KIR-driven pressure in the genesis of specific HLA-A,B haplotypes. Certain HLA-A and -B molecules are ligands for the same KIR receptors through the Bw4 binding motif spanning residues 77-83 in the α1 domain. We analyzed the HLA-A and -B genomic types of 9897 Caucasian people (3533 newborns and 6364 adults) subdividing them according to the presence/absence of the HLA-B Bw4 serological epitope. For each HLA-B Bw4- and Bw6-cross-reactive group, we evaluated the presence/absence of HLA-A ligands for KIR3DL1 (HLA-A*23, HLA-A*24, HLA-A*32) and KIR3DL2 (HLA-A*03, HLA-A*11). The frequency of HLA-A KIR ligands significantly increased moving from the HLA-B Bw4/Bw4 to the HLA-B Bw4/Bw6 and the HLA-B Bw6/Bw6 groups among both newborns and adults (P<0.0001). Here, we suggest that, when the HLA-B KIR-ligand motif is lacking, the HLA-A KIR-ligand might have a vicarious role in controlling the natural killer cell-mediated innate immune response. Basing upon this compensatory function in the engagement of KIR receptors, we hypothesize that specific HLA-A,B ancestral haplotypes were generated.
Genes and immunity 05/2012; 13(6):452-7. · 4.22 Impact Factor
[show abstract][hide abstract] ABSTRACT: A letter in response to: Sanchez-Giron F, Villegas-Torres B, Jaramillo-Villafuerte K et al. Association of the genetic marker for abacavir hypersensitivity HLA-B*5701 with HCP5 rs2395029 in Mexican Mestizos. Pharmacogenomics 12(6), 809-814 (2011).
[show abstract][hide abstract] ABSTRACT: The transplantation of two cord blood (CB) units obtained from unrelated donors (double CBT) is an effective strategy for adult patients with hematologic malignancies. Sustained hematopoiesis after double CBT is usually derived from a single donor, and only a few transplantation recipients displaying a stable mixed donor-donor chimerism have been reported. We investigated the mechanisms underlying single-donor predominance in double CBT by studying in vitro the role of the graft-versus-graft cell-mediated immune effect in two-way mixed-lymphocyte culture, along with the contribution of differential hematopoietic progenitor (HP) potency in HP mixed cultures. Results for the two-way mixed-lymphocyte culture showed that despite the weak and variable alloantigen-specific cytotoxic potential displayed by CB mononuclear cells, an immune-mediated dominance for one of the two CB units was detected in the majority of experiments. Alloantigen-induced cytotoxic activity was directed toward both CB-HP and phytohemagglutinin (PHA)-activated T lymphoblastoid cells. The CB unit with the higher fold expansion of CD34(+) cells in single-expansion culture was prevalent in the HP mixed-expansion culture, as shown by DNA chimerism evaluation. Based on these data, we hypothesize that the dominant CB unit is able to develop prevalent cytotoxic activity toward activated lymphocytes of the other CB unit, thereby preventing them from exerting alloantigen-specific cytotoxic potential against both activated lymphocytes and HPs of the dominant unit. In accordance with this hypothesis, we propose the evaluation of alloantigen-induced cytotoxic activity generated in two-way mixed-lymphocyte culture and directed toward PHA-activated T lymphoblastoid cells as a tool to identify the potentially predominant CB unit before double CBT.
Biology of blood and marrow transplantation: journal of the American Society for Blood and Marrow Transplantation 01/2012; 18(7):1108-18. · 3.15 Impact Factor
[show abstract][hide abstract] ABSTRACT: The occurrence of cell-free foetal DNA in maternal circulation opens new possibilities in non-invasive antenatal diagnosis. Real-time polymerase chain reaction (PCR) analysis is an useful approach to foetal RhD blood group determination, thus being important in the prevention of haemolytic disease of foetus and new-born (HDFN).
Using real-time PCR assays we typed 20 samples of plasma, provided in a blinded fashion, from the International Reference Laboratory, two plasma samples sent by the "2010 Workshop on Molecular Blood Group Genotyping"; seven samples from D-negative mothers at the 16th week of gestation provided by our Hospital as prospective validation cases, and two plasma samples received from the "1(st) Collaborative study establishing the sensitivity standard for non-invasive prenatal determination of foetal RHD genotype". To confirm the RHD typing of the seven prospective samples, PCR with sequence specific primers (PCR-SSP) was applied on genomic DNA from amniocytes (5 cases) and paternal peripheral blood (2 cases).
The results for the 31 investigated samples showed 100% concordance. Our measurable benefits were: confidence with a new technology, awareness of having gained the European standard level and increased self-assurance regarding the introduction of this typing technique in prenatal diagnostics.
These results demonstrate the feasibility and accuracy of our validation protocol. RHD typing on cell-free foetal DNA is a procedure which requires particular care and a great degree of expertise for diagnostic use. International collaborations are essential for monitoring the performance of laboratories in the absence of specific quality control programmes.
[show abstract][hide abstract] ABSTRACT: Increasing the safety in Immunogenetics Labs, in the era of antiretroviral pharmacogenomics, represents an imperative goal. To this purpose, we tested saliva and buccal cells as biological sources of DNA, alternative to peripheral blood, for HLA-B*57:01 genomic typing of HIV positive patients eligible to treatment with abacavir.
Blood, saliva and buccal cells of 20 voluntary donors and 20 HIV positive patients were collected. DNA was extracted with a manual commercial kit and an automated platform. Quality and quantity of DNA was evaluated with different procedures. The suitability and reliability of DNAs for HLA-B*57:01 genotyping was checked at low and high resolution level, using PCR-SSP (sequence specific primers PCR), revPCR-SSO (reverse sequence specific oligonucleotides PCR), bead array and SBT (sequence based typing) techniques.
DNA concentrations were qualitatively very good and quantitatively comparable in all the specimens tested with an inferior yield for cotton swabs. Comparing the results of HLA typing with different methodologies, the 100% of reproducibility was achieved.
The viral load of buccal epithelial cells or saliva is extremely low. Here we demonstrated that the DNA from these alternative sources is appropriate for HLA-B*57:01 typing. We strongly recommend the use of this procedure to increase the safety in the lab when dealing with infectious samples.
Clinica chimica acta; international journal of clinical chemistry 10/2011; 412(21-22):1995-8. · 2.54 Impact Factor
[show abstract][hide abstract] ABSTRACT: HLA-DQB1*02 homozygosity was shown to be more common in patients with complicated rather than uncomplicated celiac disease (CD).
To study HLA-DQA1 and DQB1 profile in adult patients with different forms of CD, including patients with complicated and potential CD, the most affected and the most preserved histologic end of the pathologic celiac spectrum.
HLA-DQA1 and DQB1 molecular typing was performed in 218 adult CD patients (169 with uncomplicated CD, 27 with complicated CD, and 22 with potential CD) and 224 healthy stem cell donors. HLA-DQA1 and DQB1 gene polymorphism was analyzed using polymerase chain reaction sequence-specific primers and/or reverse polymerase chain reaction sequence-specific oligonucleotides techniques.
As expected, the frequency of HLA-DQB1*02 allele, DQB1*02 homozygosity, and DQB1*0302 gene were statistically different in the 4 groups. However, multivariate analysis demonstrated that patients with potential CD have a higher frequency of both HLA-DQB1*0302 and HLA-DQB1*0603 alleles and a reduced frequency of DQB1*02 homozygosity compared with patients with uncomplicated and complicated CD.
The increased frequency of DQB1*0302 and the reduced frequency of DQB1*02 homozygosity in potential CD is consistent with the idea that different clinical/pathologic evolutions might be related to different immunogeneses. This could be clinically relevant in the future.
Journal of clinical gastroenterology 06/2011; 46(1):46-50. · 2.21 Impact Factor
[show abstract][hide abstract] ABSTRACT: Even though autoantibodies to pancreatic islet cells are normally found in type 1 diabetes and insulin-resistance due to overweight is more reminiscent of type 2 diabetes, some studies have described β-cell antibodies also in maturity-onset diabetes of the young (MODY) and in type 2 diabetes. A 7-year-old girl was referred to our Unit for incidental hyperglycemia and family history of MODY2 and type 2 diabetes. Genetic evaluation confirmed mutation L134P in exon 4 of the glucokinase gene and a high HLA-risk of type 1 diabetes. During follow-up, she developed type 1 diabetes and overweight-induced metabolic syndrome. The coexistence of MODY, type 1 diabetes and overweight-induced metabolic syndrome confirms that diabetes subtype probably represents a continuum of immune and metabolic dysfunction modified by genetic factors.
[show abstract][hide abstract] ABSTRACT: Chronic fatigue syndrome (CFS) is an inflammatory disease of unknown aetiology. Researchers have proposed infectious, neurological and immunological causes of this syndrome. Recently, the xenotropic murine leukemia virus-related virus was detected in 67% of patients with CFS in a US study. This observation is in agreement with one ascertained aspect of the disease: a decreased efficiency in NK cell lytic activity in CFS patients. Here, we analyzed the genomic polymorphism of killer cell immunoglobulin-like receptors (KIRs) and their HLA class I cognate ligands in patients with certified CFS. An excess of KIR3DS1 was found in CFS patients with respect to controls, as well as an increased frequency of the genotype missing KIR2DS5. Forty-four CFS patients and 50 controls also underwent genomic typing for the HLA-ligands. In the patients, a great proportion of KIR3DL1 and KIR3DS1 receptors were found to be missing their HLA-Bw4Ile80 binding motif. We hypothesize that an excess of KIR3DS1, combined with an excess of ligand-free KIR3DL1 and KIR3DS1 receptors, may hamper the clearance of a pathogen via NK cells, thus favouring the chronicity of the infection.
Molecular Medicine Reports 05/2011; 4(3):535-40. · 1.17 Impact Factor
[show abstract][hide abstract] ABSTRACT: Uncertainty still exists on the role of polymorphisms outside the HLA-DRB1 binding site or inside the HLA-DRB3 binding groove in unrelated hematopoietic SCT (HSCT). The ideal model to solve the conundrum consists of the transplants mismatched for HLA-DRB1*14:01/*14:54 and/or for HLA-DRB3*02:01/*02:02. A task force was set up in Italy to recruit transplanted pairs defined as HLA-DRB1*14:01 before 2006, the year crucial for the proper definition of the HLA-DRB1*14:54 allele in molecular biology. Out of 2723 unrelated pairs, 189 transplanted in Italy from 1995 to 2006 were HLA-DRB1*14:01 positive; 103/189 pairs with good historical DNA were retyped for HLA-DRB1*14 and HLA-DRB3 at-high resolution level; 31/103 pairs had HLA-DRB1*14 and/or HLA-DRB3 mismatched; 99/103, having complete clinical data, underwent statistical analysis for OS, TRM, disease-free survival and acute and chronic GvHD. No significant involvement of HLA-DRB1*14:01/*14:54 or HLA-DRB3*02:01/*02:02 mismatches was found, either alone or combined. Our findings suggest that disparities at exon 3 of the HLA-DRB1 gene seem unlikely to influence the outcome after HSCT. The same may be envisaged for HLA-DRB3(*)02:01 and (*)02:02 alleles which, although differing in the Ag binding site, seem unable to modulate an appreciable immune response in an HSCT setting.
Bone marrow transplantation 10/2010; 46(7):916-22. · 3.00 Impact Factor