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Halabi S, Kaufman J. New vistas unfold: Chicken MHC molecules reveal unexpected ways to present peptides to the immune system. Front Immunol 2022; 13:886672. [PMID: 35967451 PMCID: PMC9372762 DOI: 10.3389/fimmu.2022.886672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 07/07/2022] [Indexed: 11/27/2022] Open
Abstract
The functions of a wide variety of molecules with structures similar to the classical class I and class II molecules encoded by the major histocompatibility complex (MHC) have been studied by biochemical and structural studies over decades, with many aspects for humans and mice now enshrined in textbooks as dogma. However, there is much variation of the MHC and MHC molecules among the other jawed vertebrates, understood in the most detail for the domestic chicken. Among the many unexpected features in chickens is the co-evolution between polymorphic TAP and tapasin genes with a dominantly-expressed class I gene based on a different genomic arrangement compared to typical mammals. Another important discovery was the hierarchy of class I alleles for a suite of properties including size of peptide repertoire, stability and cell surface expression level, which is also found in humans although not as extreme, and which led to the concept of generalists and specialists in response to infectious pathogens. Structural studies of chicken class I molecules have provided molecular explanations for the differences in peptide binding compared to typical mammals. These unexpected phenomena include the stringent binding with three anchor residues and acidic residues at the peptide C-terminus for fastidious alleles, and the remodelling binding sites, relaxed binding of anchor residues in broad hydrophobic pockets and extension at the peptide C-terminus for promiscuous alleles. The first few studies for chicken class II molecules have already uncovered unanticipated structural features, including an allele that binds peptides by a decamer core. It seems likely that the understanding of how MHC molecules bind and present peptides to lymphocytes will broaden considerably with further unexpected discoveries through biochemical and structural studies for chickens and other non-mammalian vertebrates.
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Affiliation(s)
- Samer Halabi
- Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Jim Kaufman
- Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
- Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
- *Correspondence: Jim Kaufman,
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2
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Abstract
Compared to the major histocompatibility complex (MHC) of typical mammals, the chicken BF/BL region is small and simple, with most of the genes playing central roles in the adaptive immune response. However, some genes of the chicken MHC are almost certainly involved in innate immunity, such as the complement component C4 and the lectin-like receptor/ligand gene pair BNK and Blec. The poorly expressed classical class I molecule BF1 is known to be recognised by natural killer (NK) cells and, analogous to mammalian immune responses, the classical class I molecules BF1 and BF2, the CD1 homologs and the butyrophilin homologs called BG may be recognised by adaptive immune lymphocytes with semi-invariant receptors in a so-called adaptate manner. Moreover, the TRIM and BG regions next to the chicken MHC, along with the genetically unlinked Y and olfactory/scavenger receptor regions on the same chromosome, have multigene families almost certainly involved in innate and adaptate responses. On this chicken microchromosome, the simplicity of the adaptive immune gene systems contrasts with the complexity of the gene systems potentially involved in innate immunity.
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Tregaskes CA, Kaufman J. Chickens as a simple system for scientific discovery: The example of the MHC. Mol Immunol 2021; 135:12-20. [PMID: 33845329 PMCID: PMC7611830 DOI: 10.1016/j.molimm.2021.03.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 03/08/2021] [Accepted: 03/17/2021] [Indexed: 01/07/2023]
Abstract
Chickens have played many roles in human societies over thousands of years, most recently as an important model species for scientific discovery, particularly for embryology, virology and immunology. In the last few decades, biomedical models like mice have become the most important model organism for understanding the mechanisms of disease, but for the study of outbred populations, they have many limitations. Research on humans directly addresses many questions about disease, but frank experiments into mechanisms are limited by practicality and ethics. For research into all levels of disease simultaneously, chickens combine many of the advantages of humans and of mice, and could provide an independent, integrated and overarching system to validate and/or challenge the dogmas that have arisen from current biomedical research. Moreover, some important systems are simpler in chickens than in typical mammals. An example is the major histocompatibility complex (MHC) that encodes the classical MHC molecules, which play crucial roles in the innate and adaptive immune systems. Compared to the large and complex MHCs of typical mammals, the chicken MHC is compact and simple, with single dominantly-expressed MHC molecules that can determine the response to infectious pathogens. As a result, some fundamental principles have been easier to discover in chickens, with the importance of generalist and specialist MHC alleles being the latest example.
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Affiliation(s)
- Clive A Tregaskes
- University of Cambridge, Department of Pathology, Tennis Court Road, Cambridge, CB2 1QP, United Kingdom
| | - Jim Kaufman
- University of Cambridge, Department of Pathology, Tennis Court Road, Cambridge, CB2 1QP, United Kingdom; University of Edinburgh, Institute for Immunology and Infection Research, Ashworth Laboratories, Kings Buildings, Edinburgh, EH9 3FL, United Kingdom.
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4
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Halabi S, Ghosh M, Stevanović S, Rammensee HG, Bertzbach LD, Kaufer BB, Moncrieffe MC, Kaspers B, Härtle S, Kaufman J. The dominantly expressed class II molecule from a resistant MHC haplotype presents only a few Marek's disease virus peptides by using an unprecedented binding motif. PLoS Biol 2021; 19:e3001057. [PMID: 33901176 PMCID: PMC8101999 DOI: 10.1371/journal.pbio.3001057] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 05/06/2021] [Accepted: 03/31/2021] [Indexed: 12/14/2022] Open
Abstract
Viral diseases pose major threats to humans and other animals, including the billions of chickens that are an important food source as well as a public health concern due to zoonotic pathogens. Unlike humans and other typical mammals, the major histocompatibility complex (MHC) of chickens can confer decisive resistance or susceptibility to many viral diseases. An iconic example is Marek's disease, caused by an oncogenic herpesvirus with over 100 genes. Classical MHC class I and class II molecules present antigenic peptides to T lymphocytes, and it has been hard to understand how such MHC molecules could be involved in susceptibility to Marek's disease, given the potential number of peptides from over 100 genes. We used a new in vitro infection system and immunopeptidomics to determine peptide motifs for the 2 class II molecules expressed by the MHC haplotype B2, which is known to confer resistance to Marek's disease. Surprisingly, we found that the vast majority of viral peptide epitopes presented by chicken class II molecules arise from only 4 viral genes, nearly all having the peptide motif for BL2*02, the dominantly expressed class II molecule in chickens. We expressed BL2*02 linked to several Marek's disease virus (MDV) peptides and determined one X-ray crystal structure, showing how a single small amino acid in the binding site causes a crinkle in the peptide, leading to a core binding peptide of 10 amino acids, compared to the 9 amino acids in all other reported class II molecules. The limited number of potential T cell epitopes from such a complex virus can explain the differential MHC-determined resistance to MDV, but raises questions of mechanism and opportunities for vaccine targets in this important food species, as well as providing a basis for understanding class II molecules in other species including humans.
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Affiliation(s)
- Samer Halabi
- University of Cambridge, Department of Pathology, Cambridge, United Kingdom
- University of Edinburgh, Institute for Immunology and Infection Research, Edinburgh, United Kingdom
| | - Michael Ghosh
- University of Tübingen, Department of Immunology, Institute of Cell Biology, Tübingen, Germany
| | - Stefan Stevanović
- University of Tübingen, Department of Immunology, Institute of Cell Biology, Tübingen, Germany
| | - Hans-Georg Rammensee
- University of Tübingen, Department of Immunology, Institute of Cell Biology, Tübingen, Germany
| | | | | | | | - Bernd Kaspers
- Ludwig Maximillians University, Veterinary Faculty, Planegg, Germany
| | - Sonja Härtle
- Ludwig Maximillians University, Veterinary Faculty, Planegg, Germany
| | - Jim Kaufman
- University of Cambridge, Department of Pathology, Cambridge, United Kingdom
- University of Edinburgh, Institute for Immunology and Infection Research, Edinburgh, United Kingdom
- University of Cambridge, Department of Veterinary Medicine, Cambridge, United Kingdom
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5
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Kaufman J. From Chickens to Humans: The Importance of Peptide Repertoires for MHC Class I Alleles. Front Immunol 2020; 11:601089. [PMID: 33381122 PMCID: PMC7767893 DOI: 10.3389/fimmu.2020.601089] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/30/2020] [Indexed: 12/21/2022] Open
Abstract
In humans, killer immunoglobulin-like receptors (KIRs), expressed on natural killer (NK) and thymus-derived (T) cells, and their ligands, primarily the classical class I molecules of the major histocompatibility complex (MHC) expressed on nearly all cells, are both polymorphic. The variation of this receptor-ligand interaction, based on which alleles have been inherited, is known to play crucial roles in resistance to infectious disease, autoimmunity, and reproduction in humans. However, not all the variation in response is inherited, since KIR binding can be affected by a portion of the peptide bound to the class I molecules, with the particular peptide presented affecting the NK response. The extent to which the large multigene family of chicken immunoglobulin-like receptors (ChIRs) is involved in functions similar to KIRs is suspected but not proven. However, much is understood about the two MHC-I molecules encoded in the chicken MHC. The BF2 molecule is expressed at a high level and is thought to be the predominant ligand of cytotoxic T lymphocytes (CTLs), while the BF1 molecule is expressed at a much lower level if at all and is thought to be primarily a ligand for NK cells. Recently, a hierarchy of BF2 alleles with a suite of correlated properties has been defined, from those expressed at a high level on the cell surface but with a narrow range of bound peptides to those expressed at a lower level on the cell surface but with a very wide repertoire of bound peptides. Interestingly, there is a similar hierarchy for human class I alleles, although the hierarchy is not as wide. It is a question whether KIRs and ChIRs recognize class I molecules with bound peptide in a similar way, and whether fastidious to promiscuous hierarchy of class I molecules affect both T and NK cell function. Such effects might be different from those predicted by the similarities of peptide-binding based on peptide motifs, as enshrined in the idea of supertypes. Since the size of peptide repertoire can be very different for alleles with similar peptide motifs from the same supertype, the relative importance of these two properties may be testable.
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Affiliation(s)
- Jim Kaufman
- School of Biological Sciences, Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom.,Department of Pathology, University of Cambridge, Cambridge, United Kingdom
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6
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Potts ND, Bichet C, Merat L, Guitton E, Krupa AP, Burke TA, Kennedy LJ, Sorci G, Kaufman J. Development and optimization of a hybridization technique to type the classical class I and class II B genes of the chicken MHC. Immunogenetics 2019; 71:647-663. [PMID: 31761978 PMCID: PMC6900278 DOI: 10.1007/s00251-019-01149-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 11/17/2019] [Indexed: 01/02/2023]
Abstract
The classical class I and class II molecules of the major histocompatibility complex (MHC) play crucial roles in immune responses to infectious pathogens and vaccines as well as being important for autoimmunity, allergy, cancer and reproduction. These classical MHC genes are the most polymorphic known, with roughly 10,000 alleles in humans. In chickens, the MHC (also known as the BF-BL region) determines decisive resistance and susceptibility to infectious pathogens, but relatively few MHC alleles and haplotypes have been described in any detail. We describe a typing protocol for classical chicken class I (BF) and class II B (BLB) genes based on a hybridization method called reference strand-mediated conformational analysis (RSCA). We optimize the various steps, validate the analysis using well-characterized chicken MHC haplotypes, apply the system to type some experimental lines and discover a new chicken class I allele. This work establishes a basis for typing the MHC genes of chickens worldwide and provides an opportunity to correlate with microsatellite and with single nucleotide polymorphism (SNP) typing for approaches involving imputation.
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Affiliation(s)
- Nicola D Potts
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK.,LGC Ltd., Newmarket Road, Fordham, Ely, CB7 5WW, UK
| | - Coraline Bichet
- BioGéoSciences, CNRS UMR 5561, Université de Bourgogne Franche-Comté, 6 Boulevard Gabriel, 21000, Dijon, France.,Institute of Avian Research, An der Vogelwarte 21, 26386, Wilhelmshaven, Germany
| | - Laurence Merat
- Plate-Forme d'Infectiologie Expérimentale (PFIE), UE-1277, INRA Centre Val de Loire, 37380, Nouzilly, France
| | - Edouard Guitton
- Plate-Forme d'Infectiologie Expérimentale (PFIE), UE-1277, INRA Centre Val de Loire, 37380, Nouzilly, France
| | - Andrew P Krupa
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, S10 2TN, Sheffield, UK
| | - Terry A Burke
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, S10 2TN, Sheffield, UK
| | - Lorna J Kennedy
- Division of Population Health, Health Services Research & Primary Care, University of Manchester, Oxford Road, M13 9PL, Manchester, UK
| | - Gabriele Sorci
- BioGéoSciences, CNRS UMR 5561, Université de Bourgogne Franche-Comté, 6 Boulevard Gabriel, 21000, Dijon, France
| | - Jim Kaufman
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK. .,Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK.
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7
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Afrache H, Tregaskes CA, Kaufman J. A potential nomenclature for the Immuno Polymorphism Database (IPD) of chicken MHC genes: progress and problems. Immunogenetics 2019; 72:9-24. [PMID: 31741010 PMCID: PMC6971145 DOI: 10.1007/s00251-019-01145-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 10/20/2019] [Indexed: 12/25/2022]
Abstract
Among the genes with the highest allelic polymorphism and sequence diversity are those encoding the classical class I and class II molecules of the major histocompatibility complex (MHC). Although many thousands of MHC sequences have been deposited in general sequence databases like GenBank, the availability of curated MHC sequences with agreed nomenclature has been enormously beneficial. Along with the Immuno Polymorphism Database-IMunoGeneTics/human leukocyte antigen (IPD-IMGT/HLA) database, a collection of databases for curated sequences of immune importance has been developed. A recent addition is an IPD-MHC database for chickens. For many years, the nomenclature system for chicken MHC genes has been based on a list of standard, presumed to be stable, haplotypes. However, these standard haplotypes give different names to identical sequences. Moreover, the discovery of new recombinants between haplotypes and a rapid increase in newly discovered alleles leaves the old system untenable. In this review, a new nomenclature is considered, for which alleles of different loci are given names based on the system used for other MHCs, and then haplotypes are named according to the alleles present. The new nomenclature system is trialled, first with standard haplotypes and then with validated sequences from the scientific literature. In the trial, some class II B sequences were found in both class II loci, presumably by gene conversion or inversion, so that identical sequences would receive different names. This situation prompts further suggestions to the new nomenclature system. In summary, there has been progress, but also problems, with the new IPD-MHC system for chickens.
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Affiliation(s)
- Hassnae Afrache
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Clive A Tregaskes
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Jim Kaufman
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK. .,Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB2 0ES, UK.
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Chakraborty P, Kuo R, Vervelde L, Dutia BM, Kaiser P, Smith J. Macrophages from Susceptible and Resistant Chicken Lines have Different Transcriptomes following Marek's Disease Virus Infection. Genes (Basel) 2019; 10:genes10020074. [PMID: 30678299 PMCID: PMC6409778 DOI: 10.3390/genes10020074] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/10/2019] [Accepted: 01/21/2019] [Indexed: 12/12/2022] Open
Abstract
Despite successful control by vaccination, Marek’s disease (MD) has continued evolving to greater virulence over recent years. To control MD, selection and breeding of MD-resistant chickens might be a suitable option. MHC-congenic inbred chicken lines, 61 and 72, are highly resistant and susceptible to MD, respectively, but the cellular and genetic basis for these phenotypes is unknown. Marek’s disease virus (MDV) infects macrophages, B-cells, and activated T-cells in vivo. This study investigates the cellular basis of resistance to MD in vitro with the hypothesis that resistance is determined by cells active during the innate immune response. Chicken bone marrow-derived macrophages from lines 61 and 72 were infected with MDV in vitro. Flow cytometry showed that a higher percentage of macrophages were infected in line 72 than in line 61. A transcriptomic study followed by in silico functional analysis of differentially expressed genes was then carried out between the two lines pre- and post-infection. Analysis supports the hypothesis that macrophages from susceptible and resistant chicken lines display a marked difference in their transcriptome following MDV infection. Resistance to infection, differential activation of biological pathways, and suppression of oncogenic potential are among host defense strategies identified in macrophages from resistant chickens.
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Affiliation(s)
- Pankaj Chakraborty
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK; (P.C.); (R.K.); (L.V.); (B.M.D.)
- Chittagong Veterinary and Animal Sciences University, Khulshi, Chittagong 4225, Bangladesh
| | - Richard Kuo
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK; (P.C.); (R.K.); (L.V.); (B.M.D.)
| | - Lonneke Vervelde
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK; (P.C.); (R.K.); (L.V.); (B.M.D.)
| | - Bernadette M. Dutia
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK; (P.C.); (R.K.); (L.V.); (B.M.D.)
| | - Pete Kaiser
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK; (P.C.); (R.K.); (L.V.); (B.M.D.)
| | - Jacqueline Smith
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK; (P.C.); (R.K.); (L.V.); (B.M.D.)
- Correspondence: ; Tel.: +44-(0)131-6519155
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9
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Mucksová J, Plachý J, Staněk O, Hejnar J, Kalina J, Benešová B, Trefil P. Cytokine response to the RSV antigen delivered by dendritic cell-directed vaccination in congenic chicken lines. Vet Res 2017; 48:18. [PMID: 28381295 PMCID: PMC5382389 DOI: 10.1186/s13567-017-0423-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 01/12/2017] [Indexed: 01/05/2023] Open
Abstract
Systems of antigen delivery into antigen-presenting cells represent an important novel strategy in chicken vaccine development. In this study, we verified the ability of Rous sarcoma virus (RSV) antigens fused with streptavidin to be targeted by specific biotinylated monoclonal antibody (anti-CD205) into dendritic cells and induce virus-specific protective immunity. The method was tested in four congenic lines of chickens that are either resistant or susceptible to the progressive growth of RSV-induced tumors. Our analyses confirmed that the biot-anti-CD205-SA-FITC complex was internalized by chicken splenocytes. In the cytokine expression profile, several significant differences were evident between RSV-challenged progressor and regressor chicken lines. A significant up-regulation of IL-2, IL-12, IL-15, and IL-18 expression was detected in immunized chickens of both regressor and progressor groups. Of these cytokines, IL-2 and IL-12 were most up-regulated 14 days post-challenge (dpc), while IL-15 and IL-18 were most up-regulated at 28 dpc. On the contrary, IL-10 expression was significantly down-regulated in all immunized groups of progressor chickens at 14 dpc. We detected significant up-regulation of IL-17 in the group of immunized progressors. LITAF down-regulation with iNOS up-regulation was especially observed in the progressor group of immunized chickens that developed large tumors. Based on the increased expression of cytokines specific for activated dendritic cells, we conclude that our system is able to induce partial stimulation of specific cell types involved in cell-mediated immunity.
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Affiliation(s)
- Jitka Mucksová
- BIOPHARM, Research Institute of Biopharmacy and Veterinary Drugs, Jílové U Prahy, Czech Republic
| | - Jiří Plachý
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Ondřej Staněk
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jiří Hejnar
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jiří Kalina
- BIOPHARM, Research Institute of Biopharmacy and Veterinary Drugs, Jílové U Prahy, Czech Republic
| | - Barbora Benešová
- BIOPHARM, Research Institute of Biopharmacy and Veterinary Drugs, Jílové U Prahy, Czech Republic
| | - Pavel Trefil
- BIOPHARM, Research Institute of Biopharmacy and Veterinary Drugs, Jílové U Prahy, Czech Republic.
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Bateson ZW, Hammerly SC, Johnson JA, Morrow ME, Whittingham LA, Dunn PO. Specific alleles at immune genes, rather than genome‐wide heterozygosity, are related to immunity and survival in the critically endangered Attwater's prairie‐chicken. Mol Ecol 2016; 25:4730-44. [DOI: 10.1111/mec.13793] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 07/17/2016] [Accepted: 07/19/2016] [Indexed: 12/20/2022]
Affiliation(s)
- Zachary W. Bateson
- Behavioral and Molecular Ecology Group Department of Biological Sciences University of Wisconsin‐Milwaukee PO Box 413 Milwaukee WI 53201 USA
| | - Susan C. Hammerly
- Department of Biological Sciences Institute of Applied Sciences University of North Texas 1155 Union Circle Denton TX 76203 USA
| | - Jeff A. Johnson
- Department of Biological Sciences Institute of Applied Sciences University of North Texas 1155 Union Circle Denton TX 76203 USA
| | - Michael E. Morrow
- Attwater Prairie Chicken National Wildlife Refuge PO Box 519 Eagle Lake TX 77434 USA
| | - Linda A. Whittingham
- Behavioral and Molecular Ecology Group Department of Biological Sciences University of Wisconsin‐Milwaukee PO Box 413 Milwaukee WI 53201 USA
| | - Peter O. Dunn
- Behavioral and Molecular Ecology Group Department of Biological Sciences University of Wisconsin‐Milwaukee PO Box 413 Milwaukee WI 53201 USA
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11
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Rogers SL, Kaufman J. Location, location, location: the evolutionary history of CD1 genes and the NKR-P1/ligand systems. Immunogenetics 2016; 68:499-513. [PMID: 27457887 PMCID: PMC5002281 DOI: 10.1007/s00251-016-0938-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 07/04/2016] [Indexed: 01/14/2023]
Abstract
CD1 genes encode cell surface molecules that present lipid antigens to various kinds of T lymphocytes of the immune system. The structures of CD1 genes and molecules are like the major histocompatibility complex (MHC) class I system, the loading of antigen and the tissue distribution for CD1 molecules are like those in the class II system, and phylogenetic analyses place CD1 between class I and class II sequences, altogether leading to the notion that CD1 is a third ancient system of antigen presentation molecules. However, thus far, CD1 genes have only been described in mammals, birds and reptiles, leaving major questions as to their origin and evolution. In this review, we recount a little history of the field so far and then consider what has been learned about the structure and functional attributes of CD1 genes and molecules in marsupials, birds and reptiles. We describe the central conundrum of CD1 evolution, the genomic location of CD1 genes in the MHC and/or MHC paralogous regions in different animals, considering the three models of evolutionary history that have been proposed. We describe the natural killer (NK) receptors NKR-P1 and ligands, also found in different genomic locations for different animals. We discuss the consequence of these three models, one of which includes the repudiation of a guiding principle for the last 20 years, that two rounds of genome-wide duplication at the base of the vertebrates provided the extra MHC genes necessary for the emergence of adaptive immune system of jawed vertebrates.
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Affiliation(s)
- Sally L Rogers
- Department of Biosciences, University of Gloucestershire, Cheltenham, GL50 4AZ, UK
| | - Jim Kaufman
- Department of Pathology, University of Cambridge, Cambridge, CB2 1QP, UK. .,Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, UK.
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12
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Ohta Y, Flajnik MF. Coevolution of MHC genes (LMP/TAP/class Ia, NKT-class Ib, NKp30-B7H6): lessons from cold-blooded vertebrates. Immunol Rev 2016; 267:6-15. [PMID: 26284468 DOI: 10.1111/imr.12324] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Comparative immunology provides the long view of what is conserved across all vertebrate taxa versus what is specific to particular organisms or group of organisms. Regarding the major histocompatibility complex (MHC) and coevolution, three striking cases have been revealed in cold-blooded vertebrates: lineages of class Ia antigen-processing and -presenting genes, evolutionary conservation of NKT-class Ib recognition, and the ancient emergence of the natural cytotoxicity receptor NKp30 and its ligand B7H6. While coevolution of transporter associated with antigen processing (TAP) and class Ia has been documented in endothermic birds and two mammals, lineages of LMP7 are restricted to ectotherms. The unambiguous discovery of natural killer T (NKT) cells in Xenopus demonstrated that NKT cells are not restricted to mammals and are likely to have emerged at the same time in evolution as classical α/β and γ/δ T cells. NK cell receptors evolve at a rapid rate, and orthologues are nearly impossible to identify in different vertebrate classes. By contrast, we have detected NKp30 in all gnathostomes, except in species where it was lost. The recently discovered ligand of NKp30, B7H6, shows strong signs of coevolution with NKp30 throughout evolution, i.e. coincident loss or expansion of both genes in some species. NKp30 also offers an attractive IgSF candidate for the invasion of the RAG transposon, which is believed to have initiated T-cell receptor/immunoglobulin adaptive immunity. Besides reviewing these intriguing features of MHC evolution and coevolution, we offer suggestions for future studies and propose a model for the primordial or proto MHC.
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Affiliation(s)
- Yuko Ohta
- Department of Microbiology and Immunology, University of Maryland Baltimore School of Medicine, Baltimore, MD, USA
| | - Martin F Flajnik
- Department of Microbiology and Immunology, University of Maryland Baltimore School of Medicine, Baltimore, MD, USA
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13
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Miller MM, Taylor RL. Brief review of the chicken Major Histocompatibility Complex: the genes, their distribution on chromosome 16, and their contributions to disease resistance. Poult Sci 2016; 95:375-92. [PMID: 26740135 PMCID: PMC4988538 DOI: 10.3382/ps/pev379] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 11/11/2015] [Indexed: 12/25/2022] Open
Abstract
Nearly all genes presently mapped to chicken chromosome 16 (GGA 16) have either a demonstrated role in immune responses or are considered to serve in immunity by reason of sequence homology with immune system genes defined in other species. The genes are best described in regional units. Among these, the best known is the polymorphic major histocompatibility complex-B (MHC-B) region containing genes for classical peptide antigen presentation. Nearby MHC-B is a small region containing two CD1 genes, which encode molecules known to bind lipid antigens and which will likely be found in chickens to present lipids to specialized T cells, as occurs with CD1 molecules in other species. Another region is the MHC-Y region, separated from MHC-B by an intervening region of tandem repeats. Like MHC-B, MHC-Y is polymorphic. It contains specialized class I and class II genes and c-type lectin-like genes. Yet another region, separated from MHC-Y by the single nucleolar organizing region (NOR) in the chicken genome, contains olfactory receptor genes and scavenger receptor genes, which are also thought to contribute to immunity. The structure, distribution, linkages and patterns of polymorphism in these regions, suggest GGA 16 evolves as a microchromosome devoted to immune defense. Many GGA 16 genes are polymorphic and polygenic. At the moment most disease associations are at the haplotype level. Roles of individual MHC genes in disease resistance are documented in only a very few instances. Provided suitable experimental stocks persist, the availability of increasingly detailed maps of GGA 16 genes combined with new means for detecting genetic variability will lead to investigations defining the contributions of individual loci and more applications for immunogenetics in breeding healthy poultry.
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Affiliation(s)
- Marcia M Miller
- Beckman Research Institute, City of Hope, Department of Molecular and Cellular Biology, Duarte, CA 91010
| | - Robert L Taylor
- Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV 26506
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Genetic variability, evidence of potential recombinational event and selection of LEI0258 in chicken. Gene 2013; 537:126-31. [PMID: 24374474 DOI: 10.1016/j.gene.2013.12.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 12/16/2013] [Accepted: 12/17/2013] [Indexed: 01/18/2023]
Abstract
The chicken major histocompatibility complex (MHC) plays an important role in the immune response, disease resistance, productivity, and other important economic traits of the chicken. Therefore, a description of the polymorphisms of this region is crucial for understanding the genetic pattern of the MHC. The tandem repeat LEI0258 is located within the B region of the chicken MHC and is surprisingly strongly associated with serology. This marker has been used worldwide to provide a picture of the core area of the chicken MHC-B region and to categorize chicken MHC haplotypes. Thus, insight into the evolutionary pattern of LEI0258 may be useful for understanding MHC diversity. In the current study, 30 alleles of LEI0258 from 12 populations were screened and sequenced, and alleles that have previously been published in GenBank were also analyzed. The resulting 124 alleles were classified into four clusters according to the SNPs and indels found within the sequences flanking the repeats. Furthermore, a recombination region was identified between -30 and +43 that suggests that recombination may have played a role in the evolution of this MHC. Finally, strong evidence regarding the selection and evolutionary dynamics of the LEI0258 region is presented. Generally speaking, microsatellite is a classic anonymous marker which changes by genetic drift rather than by direct selection. Although, the genotypes of LEI0258 in MHC-B correlate with serology, its mechanism of inheritance and evolution was unclear. This study not only establishes a framework of further diversity or association studies in LEI0258, but also unraveling the reason what driving force and formulate the evolutionary dynamics of this region.
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Straub C, Neulen ML, Sperling B, Windau K, Zechmann M, Jansen CA, Viertlboeck BC, Göbel TW. Chicken NK cell receptors. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2013; 41:324-333. [PMID: 23542703 DOI: 10.1016/j.dci.2013.03.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 03/19/2013] [Accepted: 03/19/2013] [Indexed: 06/02/2023]
Abstract
Natural killer cells are innate immune cells that destroy virally infected or transformed cells. They recognize these altered cells by a plethora of diverse receptors and thereby differ from other lymphocytes that use clonally distributed antigen receptors. To date, several receptor families that play a role in either activating or inhibiting NK cells have been identified in mammals. In the chicken, NK cells have been functionally and morphologically defined, however, a conclusive analysis of receptors involved in NK cell mediated functions has not been available. This is partly due to the low frequencies of NK cells in blood or spleen that has hampered their intensive characterization. Here we will review recent progress regarding the diverse NK cell receptor families, with special emphasis on novel families identified in the chicken genome with potential as chicken NK cell receptors.
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MESH Headings
- Animals
- Antigens, CD/genetics
- Antigens, CD/immunology
- Chickens/genetics
- Chickens/immunology
- Gene Expression Regulation
- Genome/immunology
- Immunity, Innate
- Killer Cells, Natural/cytology
- Killer Cells, Natural/immunology
- Lectins, C-Type/classification
- Lectins, C-Type/genetics
- Lectins, C-Type/immunology
- Ligands
- Mammals/immunology
- Phylogeny
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/immunology
- Receptors, Natural Killer Cell/classification
- Receptors, Natural Killer Cell/genetics
- Receptors, Natural Killer Cell/immunology
- Signal Transduction
- Signaling Lymphocytic Activation Molecule Family Member 1
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Affiliation(s)
- Christian Straub
- Institute for Animal Physiology, Department of Veterinary Sciences, University of Munich, Germany
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16
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Monson MS, Mendoza KM, Velleman SG, Strasburg GM, Reed KM. Expression profiles for genes in the turkey major histocompatibility complex B-locus. Poult Sci 2013; 92:1523-34. [PMID: 23687148 DOI: 10.3382/ps.2012-02951] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The major histocompatibility complex (MHC) is a highly polymorphic region of the genome essential to immune responses and animal health. In galliforms, the MHC is divided into 2 genetically unlinked regions (MHC-B and MHC-Y). Many MHC-B genes are involved in adaptive or innate immunity, yet others have nonimmune or unknown functions. The sequenced MHC-B region of the turkey (Meleagris gallopavo) contains 40 genes, the majority of which are predicted transcripts based on comparison with the chicken or quail, without direct evidence for expression. This study was designed to test for the presence of MHC-B gene transcripts in a panel of immune and nonimmune system tissues from domestic turkeys. This analysis provides the first locus-wide examination of MHC-B gene expression in any avian species. Most MHC-B genes were broadly expressed across tissues. Expression of all predicted genes was verified by reverse-transcription PCR, including B-butyrophilin 2 (BTN2), a predicted gene with no previous evidence for expression in any species. Previously undescribed splice variants were also detected and sequenced from 3 genes. Characterization of MHC-B expression patterns helps elucidate unknown gene functions and potential gene coregulation. Determining turkey MHC-B expression profiles increases our overall understanding of the avian MHC and provides a necessary resource for future research on the immunological response of these genes.
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Affiliation(s)
- M S Monson
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, 55108, USA
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17
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Butter C, Staines K, van Hateren A, Davison TF, Kaufman J. The peptide motif of the single dominantly expressed class I molecule of the chicken MHC can explain the response to a molecular defined vaccine of infectious bursal disease virus (IBDV). Immunogenetics 2013; 65:609-18. [PMID: 23644721 PMCID: PMC3710569 DOI: 10.1007/s00251-013-0705-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 04/17/2013] [Indexed: 12/22/2022]
Abstract
In contrast to typical mammals, the chicken MHC (the BF-BL region of the B locus) has strong genetic associations with resistance and susceptibility to infectious pathogens as well as responses to vaccines. We have shown that the chicken MHC encodes a single dominantly expressed class I molecule whose peptide-binding motifs can determine resistance to viral pathogens, such as Rous sarcoma virus and Marek’s disease virus. In this report, we examine the response to a molecular defined vaccine, fp-IBD1, which consists of a fowlpox virus vector carrying the VP2 gene of infectious bursal disease virus (IBDV) fused with β-galactosidase. We vaccinated parental lines and two backcross families with fp-IBD1, challenged with the virulent IBDV strain F52/70, and measured damage to the bursa. We found that the MHC haplotype B15 from line 15I confers no protection, whereas B2 from line 61 and B12 from line C determine protection, although another locus from line 61 was also important. Using our peptide motifs, we found that many more peptides from VP2 were predicted to bind to the dominantly expressed class I molecule BF2*1201 than BF2*1501. Moreover, most of the peptides predicted to bind BF2*1201 did in fact bind, while none bound BF2*1501. Using peptide vaccination, we identified one B12 peptide that conferred protection to challenge, as assessed by bursal damage and viremia. Thus, we show the strong genetic association of the chicken MHC to a T cell vaccine can be explained by peptide presentation by the single dominantly expressed class I molecule.
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Affiliation(s)
- Colin Butter
- Institute for Animal Health, Compton, Reading, Berkshire RG20 7NN UK
- The Pirbright Institute, Compton Laboratory, Compton, RG20 7NN UK
| | - Karen Staines
- Institute for Animal Health, Compton, Reading, Berkshire RG20 7NN UK
- The Pirbright Institute, Compton Laboratory, Compton, RG20 7NN UK
| | - Andrew van Hateren
- Institute for Animal Health, Compton, Reading, Berkshire RG20 7NN UK
- Institute for Life Science, University of Southampton, Building 85, M55, Southampton, SO17 1BJ UK
| | - T. Fred Davison
- Institute for Animal Health, Compton, Reading, Berkshire RG20 7NN UK
| | - Jim Kaufman
- Institute for Animal Health, Compton, Reading, Berkshire RG20 7NN UK
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP UK
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES UK
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18
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Chazara O, Chang CS, Bruneau N, Benabdeljelil K, Fotsa JC, Kayang BB, Loukou NE, Osei-Amponsah R, Yapi-Gnaore V, Youssao IAK, Chen CF, Pinard-van der Laan MH, Tixier-Boichard M, Bed'hom B. Diversity and evolution of the highly polymorphic tandem repeat LEI0258 in the chicken MHC-B region. Immunogenetics 2013; 65:447-59. [PMID: 23529664 DOI: 10.1007/s00251-013-0697-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 03/10/2013] [Indexed: 12/15/2022]
Abstract
The chicken major histocompatibility complex (MHC) is located on the microchromosome 16 and is described as the most variable region in the genome. The genes of the MHC play a central role in the immune system. Particularly, genes encoding proteins involved in the antigen presentation to T cells. Therefore, describing the genetic polymorphism of this region is crucial in understanding host-pathogen interactions. The tandem repeat LEI0258 is located within the core area of the B region of the chicken MHC (MHC-B region) and its genotypes correlate with serology. This marker was used to provide a picture of the worldwide diversity of the chicken MHC-B region and to categorize chicken MHC haplotypes. More than 1,600 animals from 80 different populations or lines of chickens from Africa, Asia, and Europe, including wild fowl species, were genotyped at the LEI0258 locus. Fifty novel alleles were described after sequencing. The resulting 79 alleles were classified into 12 clusters, based on the SNPs and indels found within the sequences flanking the repeats. Furthermore, hypotheses were formulated on the evolutionary dynamics of the region. This study constitutes the largest variability report for the chicken MHC and establishes a framework for future diversity or association studies.
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Affiliation(s)
- Olympe Chazara
- Génétique Animale et Biologie Intégrative, INRA, AgroParisTech, UMR 1313, Jouy-en-Josas, France.
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19
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20
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Zhang L, Katselis GS, Moore RE, Lekpor K, Goto RM, Hunt HD, Lee TD, Miller MM. MHC class I target recognition, immunophenotypes and proteomic profiles of natural killer cells within the spleens of day-14 chick embryos. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2012; 37:446-456. [PMID: 22446732 DOI: 10.1016/j.dci.2012.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 03/08/2012] [Accepted: 03/11/2012] [Indexed: 05/31/2023]
Abstract
Chicken natural killer (NK) cells are not well defined, so little is known about the molecular interactions controlling their activity. At day 14 of embryonic development, chick spleens are a rich source of T-cell-free CD8αα(+), CD3(-) cells with natural killing activity. Cell-mediated cytotoxicity assays revealed complex NK cell discrimination of MHC class I, suggesting the presence of multiple NK cell receptors. Immunophenotyping of freshly isolated and recombinant chicken interleukin-2-stimulated d14E CD8αα(+) CD3(-) splenocytes provided further evidence for population heterogeneity. Complex patterns of expression were found for CD8α, chB6 (Bu-1), CD1-1, CD56 (NCAM), KUL01, CD5, and CD44. Mass spectrometry-based proteomics revealed an array of NK cell proteins, including the NKR2B4 receptor. DAVID and KEGG analyses and additional immunophenotyping revealed NK cell activation pathways and evidence for monocytes within the splenocyte cultures. This study provides an underpinning for further investigation into the specificity and function of NK cells in birds.
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Affiliation(s)
- Lei Zhang
- Department of Molecular and Cellular Biology, Beckman Research Institute, City of Hope, Duarte, CA 91010-3000, USA
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21
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Haplotype variation, recombination, and gene conversion within the turkey MHC-B locus. Immunogenetics 2010; 62:465-77. [PMID: 20461369 DOI: 10.1007/s00251-010-0451-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2009] [Accepted: 04/27/2010] [Indexed: 12/18/2022]
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22
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Chaves LD, Krueth SB, Reed KM. Defining the turkey MHC: sequence and genes of the B locus. THE JOURNAL OF IMMUNOLOGY 2009; 183:6530-7. [PMID: 19864609 DOI: 10.4049/jimmunol.0901310] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The MHC, the most polymorphic and gene dense region in the vertebrate genome, contains many loci essential to immunity. In mammals, this region spans approximately 4 Mb. Studies of avian species have found the MHC to be greatly reduced in size and gene content with an overall locus organization differing from that of mammals. The chicken MHC has been mapped to two distinct regions (MHC-B and -Y) of a single chromosome. MHC-B haplotypes possess tightly linked genes encoding the classical MHC molecules and few other disease resistance genes. Furthermore, chicken haplotypes possess a dominantly expressed class I and class II B locus that have a significant effect on the progression or regression of pathogenic disease. In this study, we present the MHC-B region of the turkey (Meleagris gallopavo) as a similarly constricted locus, with 34 genes identified within a 0.2-Mb region in near-perfect synteny with that of the chicken MHC-B. Notable differences between the two species are three BG and class II B loci in the turkey compared with one BG and two class II B loci in the chicken MHC-B. The relative size and high level of similarity of the turkey MHC in relation to that of the chicken suggest that similar associations with disease susceptibility and resistance may also be found in turkey.
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Affiliation(s)
- Lee D Chaves
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.
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Cooley AM, Willis JH. Genetic divergence causes parallel evolution of flower color in Chilean Mimulus. THE NEW PHYTOLOGIST 2009; 183:729-739. [PMID: 19453433 DOI: 10.1111/j.1469-8137.2009.02858.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Deciphering the genetic architecture of phenotypic change provides a framework for understanding how evolution proceeds at a genetic level, and paves the way for work at the molecular level. A series of intra- and interspecific crosses were used to investigate the genetic control of recently evolved floral pigmentation phenotypes in a group of closely related Mimulus species from central Chile. An intraspecific polymorphism was found to be controlled by a single Mendelian locus. Differences between species, by contrast, were composed of multiple independent patterning elements, including both Mendelian and polygenic traits. The most striking phenotypic novelty in this group, anthocyanin pigmentation in the petal lobes, has evolved three times independently. The results illustrate how genetically simple modular elements can interact with polygenic or quantitative traits to create complex new phenotypes. The repeated evolution of petal lobe anthocyanins suggests that natural selection may have played a role in the evolution of red coloration in the Chilean Mimulus, and shows that red coloration has been achieved via different genetic pathways in these closely related species.
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Affiliation(s)
| | - John H Willis
- Department of Biology, Duke University, Durham, NC 27708, USA
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24
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Abstract
Natural killer (NK) activity has been examined in birds for over 30 years, but evidence that avian NK activity plays crucial roles in disease is only suggestive. In chickens, NK activity is mediated by TCR0 cells in the intestinal epithelium, but elsewhere subsets of alphabeta and gammadelta T cells (NKT cells) may be more important. There are few lectin-like NK receptor genes, located in the genomic region syntenic with the natural killer complex (NKC) as well as the major histocompatibility complex (MHC). In contrast, a huge number of Ig-like receptor genes are located in a region syntenic with the leukocyte receptor complex (LRC).
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