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ABSTRACT: Brucella abortus is an intracellular pathogen that progresses the crafty strategy to invade and proliferate within host cells, but the distinct signaling pathways associated with phagocytic mechanisms of B. abortus remain unclear. The present study was performed to test the hypothesis that Toll-like receptor 4 (TLR4) -linked signaling interacting with Janus kinase 2 (JAK2) plays an essential role in B. abortus phagocytosis by macrophages. The effects of TLR4-JAK2 signaling on B. abortus phagocytosis into murine macrophage RAW264.7 were observed through infection assay and confocal microscopy. We determined that the uptake of B. abortus was negatively affected by the dysfunction of TLR4 and JAK2. F-actin polymerization detected by flow cytometry and F-actin assay was amplified for B. abortus entry, whereas that event was attenuated by the disruption of TLR4 and JAK2. Importantly, JAK2 phosphorylation and actin skeleton reorganization were suppressed immediately after B. abortus infection in bone marrow-derived macrophages (BMDMs) from TLR4(-/-) mice, showing the cooperation of JAK2 with TLR4. Furthermore, small GTPase Cdc42 participated in the intermediate pathway of TLR4-JAK2 signaling on B. abortus phagocytosis. Consequently, TLR4-associated JAK2 activation in the early cellular signaling events plays a pivotal role in B. abortus-induced phagocytic process in macrophages, implying the pathogenic significance of JAK2-mediated entry. Here, we elucidate that this specific phagocytic mechanism of B. abortus might provide achievable strategies for inhibiting B. abortus invasion.
Infection and immunity 04/2013; · 4.21 Impact Factor
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ABSTRACT: The molecular and cellular mechanisms leading to immune protection against Eimeria avian coccidiosis are complex and include multiple aspects of innate and adaptive immunities. Innate immunity is mediated by various subpopulations of immune cells that recognize pathogen associated molecular patterns (PAMPs) through their pattern recognition receptors (PRRs) leading to the secretion of soluble factors with diverse functions. Adaptive immunity, which is important in conferring protection against subsequent reinfections, involves subtypes of T and B lymphocytes that mediate antigen-specific immune responses. Recently, global gene expression microarray analysis has been used in an attempt to dissect this complex network of immune cells and molecules during avian coccidiosis. These new studies emphasized the uniqueness of the innate immune response to Eimeria infection, and directly led to the discovery of previously uncharacterized host genes and proteins whose expression levels were modulated following parasite infection. Among these is the IL-17 family of cytokines. This review highlights recent progress in IL-17 research in the context of host immunity to avian coccidiosis.
Developmental and comparative immunology 04/2013; · 3.29 Impact Factor
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ABSTRACT: The Clostridium-related poultry disease, necrotic enteritis (NE), causes substantial economic losses on a global scale. In the present study, a mixture of two plant-derived phytonutrients, Capsicum oleoresin and turmeric oleoresin (XT), was evaluated for its effects on local and systemic immune responses using a co-infection model of experimental NE in commercial broilers. Chickens were fed from hatch with a diet supplemented with XT, or with a non-supplemented control diet, and either uninfected or orally challenged with virulent Eimeria maxima oocysts at 14 d and Clostridium perfringens at 18 d of age. Parameters of protective immunity were as follows: (1) body weight; (2) gut lesions; (3) serum levels of C. perfringens α-toxin and NE B-like (NetB) toxin; (4) serum levels of antibodies to α-toxin and NetB toxin; (5) levels of gene transcripts encoding pro-inflammatory cytokines and chemokines in the intestine and spleen. Infected chickens fed the XT-supplemented diet had increased body weight and reduced gut lesion scores compared with infected birds given the non-supplemented diet. The XT-fed group also displayed decreased serum α-toxin levels and reduced intestinal IL-8, lipopolysaccharide-induced TNF-α factor (LITAF), IL-17A and IL-17F mRNA levels, while cytokine/chemokine levels in splenocytes increased in the XT-fed group, compared with the animals fed the control diet. In conclusion, the present study documents the molecular and cellular immune changes following dietary supplementation with extracts of Capsicum and turmeric that may be relevant to protective immunity against avian NE.
The British journal of nutrition 04/2013; · 3.45 Impact Factor
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ABSTRACT: AIMS: To clarify the effects of Phellinus baumii ethanol extract (PBE) on Brucella abortus pathogenesis in phagocytes focusing on the phagocytic and intracellular trafficking pathway. METHODS AND RESULTS: The effects of PBE on B. abortus infection in macrophages were evaluated through an adherence and infection assays and an analysis of LAMP-1 staining. The phosphorylation of ERK1/2 and the F-actin polymerization associated with PBE during B. abortus uptake were detected by immunoblotting and FACS, respectively. The survival of B. abortus in pure culture was remarkably reduced by PBE in a dose-dependent manner. PBE-treated cells showed significantly decreased uptake, intracellular replication and adherence of B. abortus. The declines of ERK1/2 phosphorylation and F-actin polymerization following B. abortus entry were apparent in PBE-treated cells compared to the control. Moreover, the colocalization of B. abortus-containing phagosomes with LAMP-1 was elevated in PBE-treated cells compared to the control during intracellular trafficking. CONCLUSION: PBE may possess the modulatory effect on pathogenesis of B. abortus through disrupting the phagocytic and intracellular trafficking pathway in phagocyte. © 2012The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.
Journal of Applied Microbiology 11/2012; · 2.34 Impact Factor
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ABSTRACT: Interleukin-17F (IL-17F) is a proinflammatory cytokine, which plays an important role in gut homeostasis. A full-length chicken IL-17F (chIL-17F) cDNA with a 510-bp coding region was identified from ConA-activated chicken splenic lymphocytes. ChIL-17F shares 53% amino acid sequence identity with the previously described chicken IL-17 (chIL-17A) and 38-43% with mammalian homologues. The locus harboring chIL-17 and chIL-17F displayed inverted order compared to those of mammals. ChIL-17F transcript expression was high in lymphoblast cell line CU205 and at moderate levels in small and large intestines and liver. ChIL-17F and chIL-17 expression profiles were examined by quantitative real-time RT-PCR in mitogen-stimulated splenic lymphocytes and intestinal areas affected by Eimeria maxima and Eimeria tenella infections. Expression levels of chIL-17F, like chIL-17, were elevated in mitogen-activated splenic lymphocytes. ChIL-17F, but not chIL-17, expression was upregulated in intestinal tissues affected by E. maxima and E. tenella infections. Recombinant chIL-17F biological activities were similar to that of chIL-17 in primary chicken embryonic fibroblasts. These results suggest that chIL-17F is a unique member of the IL-17 family of cytokines.
Developmental and comparative immunology 08/2012; · 3.29 Impact Factor
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Jin Ju Lee,
Dong Hyeok Kim,
Jeong Ju Lim,
Dae Geun Kim, Wongi Min,
Gon Sup Kim,
Hu Jang Lee,
Man Hee Rhee,
Hyun Park,
Sam Churl Kim,
Hong Hee Chang,
Suk Kim
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ABSTRACT: The anticoccidial effects of Galla Rhois (GR) powder, which contains a major tannin-derived component of 52.7%, were evaluated in chickens following oral infection with Eimeria tenella. One-day-old chickens were assigned to five groups (control, unsupplemented, GR 0.5% supplemented [GRS 0.5%], GRS 1.0% [GRS 1.0%] and salinomycin supplemented [SS]). The chickens were fed a standard diet supplemented or not supplemented with GR or salinomycin for 10 days prior to infection. The birds received the supplemented diets continuously until 10 days post infection. The effects of GR on a E. tenella infection were evaluated by several parameters, including body weight gain, feed intake, oocyst excretion, bloody diarrhoea, and lesion scores. Infected chickens on the GRS and SS diets had a relatively moderate body weight loss (reduction ratio < 15%) and improved feed conversion. GRS and SS chickens produced significantly fewer faecal oocysts (P<0.05) and showed milder bloody diarrhoea compared with the E. tenella-infected control group. Furthermore, the lesion scores of both the GRS 0.5% and GRS 1.0% groups were significantly lower than the scores of the unsupplemented group on day 5 post infection. The lesion scores for the GR groups were similar to the scores for the SS group. In conclusion, this study suggests that GR appears to be as efficacious as salinomycin against E. tenella infection. GR supplementation leads to a reduction in infected chickens, although infected chickens are still affected compared with the uninfected control group. GR-based diets may be beneficial in preventing or treating coccidial infections in poultry.
Avian Pathology 08/2012; 41(4):403-7. · 1.71 Impact Factor
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Dong Hyeok Kim,
Jeong Ju Lim,
Jin Ju Lee,
Dae Geun Kim,
Hu Jang Lee, Wongi Min,
Kwang Dong Kim,
Hong Hee Chang,
Man Hee Rhee,
Masahisa Watarai,
Suk Kim
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ABSTRACT: Brucella abortus, the causative agent of brucellosis, can survive and replicate within host cells. Understanding bacterial virulence factors and bacteria-host cell interactions is critical for controlling brucellosis, yet very little is known about the virulence strategies and signaling pathways activated in phagocytes during infection to ensure their growth and survival. B. abortus was mutagenized by mini-Tn5Km2 transposon mutagenesis to identify virulence genes related to the internalization and intracellular replication of the bacteria. Of the total 2300 mutants used to infect HeLa cells, 23 mutants defective for intercellular growth and the mutated genes were identified. Sequence analysis of DNA flanking the transposon showed various insertion sites in bacterial genes that might be associated with virulence, including genes associated with lipoproteins, amino acid metabolism, translation, transcription, carbohydrate transport, coenzyme transport, inorganic ion transport, energy metabolism, membrane transport, and cell wall/membrane biogenesis. Moreover, mutants were classified into class I, class II and class III as higher, similar, and lower internalization, respectively, into HeLa cells. Furthermore, defective mutants for intracellular growth in HeLa cells were found to be defective in RAW 264.7 cells. Taken together, we suggest that the identified virulence associated genes might contribute to the intracellular growth and survival of B. abortus in phagocytes.
Veterinary Microbiology 02/2012; 158(3-4):322-8. · 3.33 Impact Factor
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ABSTRACT: BACKGROUND: Interleukin (IL) 2 and IL15 receptor β chain (IL2/15Rβ, CD122) play critical roles in signal transduction for the biological activities of IL2 and IL15. Increased knowledge of non-mammalian IL2/15Rβ will enhance the understanding of IL2 and IL15 functions. METHOLOGY/PRINCIPAL FINDINGS: Chicken IL2/15Rβ (chIL2/15Rβ) cDNA was cloned using 5'/3'-RACE. The predicted protein sequence contained 576 amino acids and typical features of the type-I cytokine receptor family. COS-7 cells transfected with chIL2/15Rβ produced proteins of approximately 75 and 62.5 kDa under normal and tunicamycin-treated conditions, respectively. The genomic structure of chIL2/15Rβ was similar to its mammalian counterparts. chIL2/15Rβ transcripts were detected in the lymphoblast cell line CU205 and in normal lymphoid organs and at moderate levels in bursa samples. Expression profiles of chIL2/15Rβ and its related cytokines and receptors were examined in ConA-stimulated splenic lymphocytes and in ceca-tonsils of Eimeria tenella-infected chickens using quantitative real-time PCR. Expression levels of chIL2/15Rβ, chIL2Rα, and chIL15Rα were generally elevated in ceca-tonsils and ConA-activated splenic lymphocytes. However, chIL2 and chIL15 expression levels were differentially regulated between the samples. chIL2 expression was upregulated in ConA-activated splenic lymphocytes, but not in ceca-tonsils. In constrast, chIL15 expression was upregulated in ceca-tonsils, but not in ConA-activated splenic lymphocytes. CONCLUSIONS/SIGNIFICANCE: We identified an avian form of IL2/15Rβ and compared its gene expression pattern with those of chIL2, chIL15, chIL2Rα, and chIL15Rα. Our observations suggest that chIL15 and its receptors, including chIL2/15Rβ, play important roles in mucosal immunity to intestinal intracellular parasites such as Eimeria.
PLoS ONE 01/2012; 7(5):e37704. · 4.09 Impact Factor
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ABSTRACT: Brucella spp. are Gram-negative, facultative, intracellular coccobacilli that are pathogenic to a variety of mammals, including ruminants and humans. The conventional serological test for diagnosing brucellosis in cattle in Korea is the standard tube agglutination test. However, agglutination tests sometimes give false-positive results due to cross-reactions with other pathogens. The outer membrane proteins of Brucella species have been extensively studied for their immunogenicity and serodiagnostic applications. However, an application of B. abortus OMPs for serodiagnosis has not been successfully established. In this study, cloning and expression of B. abortus Omp28, a group 3 antigen, were accomplished by PCR amplification cloning into a pMAL expression system, and purification of a recombinant Omp28 (rOmp28). The immunogenicity of rOmp28 was confirmed by Western blot analysis with Brucella-positive bovine serum. To determine whether rOmp2 has a potential benefit for use in the serodiagnosis of bovine brucellosis, rOmp28-based ELISA and latex bead agglutination test were performed. B. abortus positive (n=122) or negative (n=88) from TAT were positive (118/122, 96.7%) or negative (84/88, 95.4%) in ELISA and were positive (94/122, 77%) or negative (71/88, 81.7%) in that the latex bead agglutination test, respectively. The sensitivity, specificity and accuracy were 96.7, 95.4, 96.2% in ELISA and 77, 80.6, 78.5% in latex bead agglutination test, respectively. These findings suggest that the rOmp28 of B. abortus might be a good candidate for developing serological diagnostic tools for bovine brucellosis.
Journal of Veterinary Medical Science 12/2011; 74(6):687-91. · 0.85 Impact Factor
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Dong Hyeok Kim,
Jeong Ju Lim,
Jin Ju Lee,
Dae Geun Kim,
Hu Jang Lee, Wongi Min,
Kwang Dong Kim,
Hong Hee Chang,
Mehari Endale,
Man Hee Rhee,
Masahisa Watarai,
Suk Kim
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ABSTRACT: Brucella abortus can proliferate within professional and nonprofessional phagocytic host cells and thereby successfully bypass the bacteriocidal effects of phagocytes. However, the intracellular survival mechanism and factors of virulence are not fully understood.
We have investigated the role of the regulator of G protein signaling 2 (RGS2), an intracellular calcium ([Ca(2+)](i)) regulator of the host cell, in the intracellular survival of B. abortus within phagocytes.
B. abortus infection markedly induced RGS2 messenger RNA expression in early phase and increased the [Ca(2+)](i) level up to 24 hours postinfection within macrophages from wild-type mice. The [Ca(2+)](i) level, however, was not influenced by B. abortus infection within macrophages from RGS2-deficient mice. Furthermore, B. abortus survival was reduced within RGS2-deficient macrophages, and hence bacterial proliferation was inhibited in RGS2-deficient mice. Moreover, treatment with the Ca(2+) chelator ethylenediaminetetraacetic acid (EDTA) or 1,2-bis-(2-amino-phenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTA-AM) and the L-type Ca(2+) channel-blocking agent nifedipine or genistein also showed a reduced intracellular replication of B. abortus within macrophages.
These results indicate that B. abortus infection induces host RGS2 expression and that up-regulation of [Ca(2+)](i) levels is an essential factor for the intracellular survival of B. abortus within phagocytes.
The Journal of Infectious Diseases 12/2011; 205(3):445-52. · 6.41 Impact Factor
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Jin Ju Lee,
Jae Hyung Bae,
Dong Hyeok Kim,
Jeong Ju Lim,
Dae Geun Kim,
Hu Jang Lee, Wongi Min,
Man Hee Rhee,
Hong Hee Chang,
Hyun Park,
Suk Kim
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ABSTRACT: Galla Rhois (GR) has long been applied in traditional Korean and Oriental medicine. Although GR has an anti-bacterial effect, the anti-bacterial mechanism and therapeutic efficiency of GR for intracellular parasitic Brucella infection are still unclear.
The objective of this study was to investigate the antibacterial and therapeutic effects of GR ethanol extract (GRE), which is a natural antibacterial component for the treatment of Brucella abortus infection.
The antibacterial activity of GRE towards Brucella abortus was evaluated by incubating Brucella abortus with GRE. Following treatment with GRE, Brucella abortus adherence, uptake, intracellular growth, and intracellular trafficking in macrophages were monitored. Mice were infected intraperitoneally with Brucella abortus and treated orally with GRE for 14 days, and then the weight and CFUs from each spleen were monitored.
The viability of Brucella abortus was markedly decreased in a dose-dependent manner. Moreover, Brucella abortus internalization and intracellular growth within macrophages were reduced in GRE-treated cells. The number of bacteria that adhered to GRE-pretreated cells was significantly lower than that of untreated cells. With regards to intracellular trafficking, treatment with GRE augmented the colocalization of Brucella abortus-containing phagosomes with LAMP-1. GRE-treated mice showed considerably decreased weight and bacterial burdens in the spleen compared to untreated mice.
GRE exhibits antibacterial and protective effects on Brucella abortus in vitro and in vivo. These results highlight the beneficial effects of GRE in the prevention and treatment of brucellosis.
Journal of ethnopharmacology 11/2011; 138(2):602-9. · 2.32 Impact Factor
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ABSTRACT: A total of 170 fresh fecal samples (healthy; n=137, diarrheic; n=33) were collected from pet rabbits. By using PCR and formol-ether concentration method, a total 13/137 healthy rabbit feces were positive for L. intracellularis, 6/137 for Salmonella, and 13/137 for Eimeria. On the other hand, a total 17/33 diarrheic rabbit fecal samples were positive for L. intracellularis, 10/33 for Salmonella, and 21/33 for Eimeria. From these results, more than 20% of clinically normal and 97% of diarrheic rabbits were positive for single or concurrent infection of three pathogens. To the best of our knowledge, this is the first report to describe the prevalence of the microorganisms L. intracellularis, Salmonella and Eimeria in pet rabbits.
Journal of Veterinary Medical Science 09/2011; 74(2):263-5. · 0.85 Impact Factor
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ABSTRACT: Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that plays an important role in host defense against a variety of microorganisms including protozoan parasites. Interestingly, some microbial pathogens also express a MIF-like protein, although its role in disease pathogenesis is not well understood. The aim of this study was to compare an Eimeria-encoded MIF (E.MIF) protein with chicken MIF (C.MIF) on the basis of their structural, immunological, and biological properties. E.MIF and C.MIF proteins, each with a glutathione S-transferase epitope tag, were expressed in Escherichia coli or COS-7 cells and purified by glutathione affinity chromatography. Rabbit antisera against the purified proteins demonstrated their mutual immunological cross-reactivity on Western blots, and immunolocalized intracellular native E.MIF to the Eimeria schizont, merozoite, and oocyst life cycle stages. HD11 chicken macrophages treated in vitro with C.MIF recombinant protein expressed increased levels of transcripts encoding interleukin-6 (IL-6), IL-17, and tumor necrosis factor superfamily member 15 (TNFSF15), but decreased levels of IL-8 transcripts, compared with cells treated with the PBS control; similar treatment with E.MIF only down-regulated IL-8 transcripts. Unlike recombinant E.MIF, C.MIF exhibited in vitro chemotactic activity for HD11 cells. Conversely, E.MIF, but not C.MIF, enhanced protection against experimental Eimeria infection, compared with the PBS control. These studies provide evidence for overlapping structural and antigenic properties, but distinct immunoregulatory roles, of E.MIF and C.MIF.
Vaccine 09/2011; 29(48):8998-9004. · 3.77 Impact Factor
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ABSTRACT: During experimental Eimeria infections in chickens, facilities are often contaminated by fecal oocysts known to be highly resistant to both chemical and enzymatic treatments. Thus, studies using experimental Eimeria infections have been limited due to the difficulty of complete elimination of residual oocysts from both cages and facilities. To overcome this limitation, simple, inexpensive, and disposable cages were constructed from cardboard boxes and tested during experimental Eimeria maxima infections. The cages were used in animal rooms with only a 1.7% evidence of coccidia contamination between adjacent cages. No significant differences in fecal oocyst output and body weight gain were noted between animals housed in disposable cages and animals housed in wire control cages. This cage design is a useful means for preventing oocyst contamination during experimental conditions, suggesting that this disposable cage design could be used for other avian infectious disease studies.
The Korean Journal of Parasitology 09/2011; 49(3):299-302. · 1.04 Impact Factor
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Sung Hyen Lee,
Hyun S Lillehoj,
Seung I Jang,
Cynthia Baldwin,
Dannielle Tompkins,
Bettina Wagner,
Mark Parcells,
Emilio Del Cacho,
Yeong Ho Hong, Wongi Min,
Erik P Lillehoj
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ABSTRACT: This study was carried out to develop and characterize mouse monoclonal antibodies (mAbs) against chicken CD25 (chCD25), the alpha chain of the interleukin-2 (IL-2) receptor. A recombinant chimeric chCD25/IgG4 fusion protein was expressed in Chinese hamster ovary (CHO) cells and isolated from spent cell culture medium by protein G affinity chromatography. Purified chCD25 protein was used to immunize mice, from which 54 stable hybridomas secreting chCD25 mAbs were produced. Two mAbs, chCD25-32 and chCD25-54, with high binding affinity for chCD25-expressing CHO cells were selected for further characterization. By flow cytometry, both mAbs detected cells in the spleen, bursa of Fabricius, intestinal duodenum, and immunostained established chicken T cell, B cell, and macrophage cell lines. Both mAbs reacted with a 55 kDa protein on Western blots of lysates from concanavalin A (Con A)-stimulated spleen mononuclear cells. Intraperitoneal injection of chickens with bacterial lipopolysaccharide increased the percentage of chCD25(+) spleen cells by approximately 4-fold compared with untreated animals. In vitro stimulation of spleen cells with Con A increased the percentage of chCD25(+) cells by up to 50-fold compared with cells treated with medium alone. Finally, the chCD25-32 mAb suppressed IL-2-driven spleen cell proliferation and reduced IL-2-induced nitric oxide production. These mAbs may be useful for future investigation of chicken regulatory T cells.
Veterinary Immunology and Immunopathology 08/2011; 144(3-4):396-404. · 2.08 Impact Factor
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ABSTRACT: The chicken, which is the host for seven species of Eimeria, typically is infected simultaneously by multiple Eimeria species and the oocysts of coccidia are excreted in the feces. A prerequisite for investigation of individual Eimeria species is to isolate a single oocyst from fecal samples. A novel method for isolating a single Eimeria oocyst from poultry litter using a micromanipulator was developed. This simple method is fast and reliable, and provides direct isolation of a single sporulated oocyst from fecal samples harboring multiple Eimeria species or samples contaminated by other species of parasite.
Research in Veterinary Science 04/2011; 90(2):260-1. · 1.65 Impact Factor
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ABSTRACT: Common cytokine receptor γ chain (γ(c)) family cytokines play crucial roles in the regulation of innate and adaptive immune responses. Unlike mammals, chickens possess two different γ(c) transcripts. To determine if this difference is present in other avian species, γ(c) cDNA and genomic clones from ducks and quails were investigated. Two different γ(c) transcripts were identified in both species and designated as duck γ(c)-a (duγ(c)-a), duγ(c)-b, quail γ(c)-a (quγ(c)-a), and quγ(c)-b. Comparisons between the duck and quail γ(c) cDNA and genomic sequences indicated that the two transcripts were produced by alternative splicing. Unexpectedly, the duγ(c)-b contained the fifth intron, a frame-switching 88-bp insertion, resulting in a receptor molecule lacking a transmembrane region. These findings indicate a possibility that avian species, unlike mammals, express two different γ(c) transcripts due to alternative splicing. This study is the first demonstration of an alternatively spliced γ(c) isoform that lacks a transmembrane domain.
Veterinary Immunology and Immunopathology 03/2011; 140(1-2):159-65. · 2.08 Impact Factor
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ABSTRACT: This study was carried out to develop and characterize mouse monoclonal antibodies (mAbs) against chicken CD80 (chCD80). A recombinant plasmid containing a chCD80/horse IgG4 fusion gene was constructed and expressed in CHO cells to produce recombinant chCD80/IgG4 protein. Chicken CD80 was purified from the chCD80/IgG4 fusion protein following enterokinase digestion, and used to immunize BALB/c mice, resulting in 158 hybridomas that produced mAbs against chCD80. Three mAbs with high binding specificity for recombinant chCD80/IgG4-transfected CHO cells were identified by flow cytometry, and one of these (#112) was selected for further characterization. Immunoprecipitation of CD80/IgG4-CHO cell extract, or lipopolysaccharide (LPS)-treated monocytes identified 35.0kDa proteins. Immunohistochemical analysis revealed chCD80-expressing cells exclusively in the bursal follicles at the outer portion of the cortex, and throughout the red pulp and the outer boundary of the white pulp in the spleen. By immunofluorescence microscopy, chCD80 was observed on intestinal dendritic cells. LPS treatment of bursa or spleen monocytes for 24 or 48h increased chCD80 expression. Finally, addition of chCD80 mAb to Con A-stimulated spleen cells inhibited the expression of major histocompatibility complex class II antigens and IL-2-driven proliferation of lymphoblast cells. In summary, these chCD80 mAbs will serve as valuable immunological reagents for basic and applied poultry immunology research.
Comparative immunology, microbiology and infectious diseases 02/2011; 34(3):273-9. · 2.99 Impact Factor
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ABSTRACT: Aloes have been widely used for a broad range of pharmacological activities, including parasitic problems. Avian coccidiosis is the most costly and wide-spread parasitic disease in the poultry industry, and has been mainly controlled by the use of chemotherapeutic agents. Due to the emergence of drug-resistant strains, alternative control strategies are needed. In this study, the protective effects of Aloe vera-based diets were assessed in broiler chickens following oral infection with Eimeria maxima. Chickens were fed a regular diet supplemented with ground Aloe vera throughout the duration of the experiment beginning 2 days prior to infection with 1 × 10(4) sporulated oocysts of E. maxima. No significant differences were found in body weight gain or loss between the Aloe vera-supplemented and unsupplemented groups with or without E. maxima infections. Fecal oocyst shedding decreased significantly (p < 0.05) in all of the treatment groups that were supplemented with Aloe vera as compared to the unsupplemented group. Furthermore, the Aloe vera-supplemented group showed significantly fewer intestinal lesions (p < 0.05) than the unsupplemented group following infection. The findings of this study suggest that Aloe vera could be used an alternative treatment for controlling avian coccidiosis.
Experimental Parasitology 01/2011; 127(1):322-5. · 2.12 Impact Factor
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ABSTRACT: Relative expression levels of immune- and non-immune-related mRNAs in chicken intestinal intraepithelial lymphocytes experimentally infected with Eimeria acervulina, E. maxima, or E. tenella were measured using a 10K cDNA microarray. Based on a cutoff of >2.0-fold differential expression compared with uninfected controls, relatively equal numbers of transcripts were altered by the three Eimeria infections at 1, 2, and 3 days post-primary infection. By contrast, E. tenella elicited the greatest number of altered transcripts at 4, 5, and 6 days post-primary infection, and at all time points following secondary infection. When analyzed on the basis of up- or down-regulated transcript levels over the entire 6 day infection periods, approximately equal numbers of up-regulated transcripts were detected following E. tenella primary (1,469) and secondary (1,459) infections, with a greater number of down-regulated mRNAs following secondary (1,063) vs. primary (890) infection. On the contrary, relatively few mRNA were modulated following primary infection with E. acervulina (35 up, 160 down) or E. maxima (65 up, 148 down) compared with secondary infection (E. acervulina, 1,142 up, 1,289 down; E. maxima, 368 up, 1,349 down). With all three coccidia, biological pathway analysis identified the altered transcripts as belonging to the categories of "Disease and Disorder" and "Physiological System Development and Function". Sixteen intracellular signaling pathways were identified from the differentially expressed transcripts following Eimeria infection, with the greatest significance observed following E. acervulina infection. Taken together, this new information will expand our understanding of host-pathogen interactions in avian coccidiosis and contribute to the development of novel disease control strategies.
PLoS ONE 01/2011; 6(11):e27712. · 4.09 Impact Factor
