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Vasoya D, Tzelos T, Benedictus L, Karagianni AE, Pirie S, Marr C, Oddsdóttir C, Fintl C, Connelley T. High-Resolution Genotyping of Expressed Equine MHC Reveals a Highly Complex MHC Structure. Genes (Basel) 2023; 14:1422. [PMID: 37510326 PMCID: PMC10379315 DOI: 10.3390/genes14071422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/29/2023] [Accepted: 07/04/2023] [Indexed: 07/30/2023] Open
Abstract
The Major Histocompatibility Complex (MHC) genes play a key role in a number of biological processes, most notably in immunological responses. The MHCI and MHCII genes incorporate a complex set of highly polymorphic and polygenic series of genes, which, due to the technical limitations of previously available technologies, have only been partially characterized in non-model but economically important species such as the horse. The advent of high-throughput sequencing platforms has provided new opportunities to develop methods to generate high-resolution sequencing data on a large scale and apply them to the analysis of complex gene sets such as the MHC. In this study, we developed and applied a MiSeq-based approach for the combined analysis of the expressed MHCI and MHCII repertoires in cohorts of Thoroughbred, Icelandic, and Norwegian Fjord Horses. The approach enabled us to generate comprehensive MHCI/II data for all of the individuals (n = 168) included in the study, identifying 152 and 117 novel MHCI and MHCII sequences, respectively. There was limited overlap in MHCI and MHCII haplotypes between the Thoroughbred and the Icelandic/Norwegian Fjord horses, showcasing the variation in MHC repertoire between genetically divergent breeds, and it can be inferred that there is much more MHC diversity in the global horse population. This study provided novel insights into the structure of the expressed equine MHC repertoire and highlighted unique features of the MHC in horses.
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Affiliation(s)
- Deepali Vasoya
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Roslin EH25 9RG, UK
| | - Thomas Tzelos
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Roslin EH25 9RG, UK
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK
| | - Lindert Benedictus
- Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands
| | - Anna Eleonora Karagianni
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Roslin EH25 9RG, UK
| | - Scott Pirie
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Roslin EH25 9RG, UK
| | - Celia Marr
- Rossdales Equine Hospital, Cotton End Road, Exning, Newmarket CD8 7NN, UK
| | - Charlotta Oddsdóttir
- The Institute for Experimental Pathology at Keldur, University of Iceland Keldnavegur 3, 112 Reykjavík, Iceland
| | - Constanze Fintl
- Department of Companion Animal Clinical Sciences, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, P.O. Box 5003, 1432 Ås, Norway
| | - Timothy Connelley
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Roslin EH25 9RG, UK
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Yao S, Liu J, Qi J, Chen R, Zhang N, Liu Y, Wang J, Wu Y, Gao GF, Xia C. Structural Illumination of Equine MHC Class I Molecules Highlights Unconventional Epitope Presentation Manner That Is Evolved in Equine Leukocyte Antigen Alleles. THE JOURNAL OF IMMUNOLOGY 2016; 196:1943-54. [DOI: 10.4049/jimmunol.1501352] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 12/03/2015] [Indexed: 01/20/2023]
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3
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Bergmann T, Moore C, Sidney J, Miller D, Tallmadge R, Harman RM, Oseroff C, Wriston A, Shabanowitz J, Hunt DF, Osterrieder N, Peters B, Antczak DF, Sette A. The common equine class I molecule Eqca-1*00101 (ELA-A3.1) is characterized by narrow peptide binding and T cell epitope repertoires. Immunogenetics 2015; 67:675-89. [PMID: 26399241 DOI: 10.1007/s00251-015-0872-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 09/14/2015] [Indexed: 11/29/2022]
Abstract
Here we describe a detailed quantitative peptide-binding motif for the common equine leukocyte antigen (ELA) class I allele Eqca-1*00101, present in roughly 25 % of Thoroughbred horses. We determined a preliminary binding motif by sequencing endogenously bound ligands. Subsequently, a positional scanning combinatorial library (PSCL) was used to further characterize binding specificity and derive a quantitative motif involving aspartic acid in position 2 and hydrophobic residues at the C-terminus. Using this motif, we selected and tested 9- and 10-mer peptides derived from the equine herpesvirus type 1 (EHV-1) proteome for their capacity to bind Eqca-1*00101. PSCL predictions were very efficient, with an receiver operating characteristic (ROC) curve performance of 0.877, and 87 peptides derived from 40 different EHV-1 proteins were identified with affinities of 500 nM or higher. Quantitative analysis revealed that Eqca-1*00101 has a narrow peptide-binding repertoire, in comparison to those of most human, non-human primate, and mouse class I alleles. Peripheral blood mononuclear cells from six EHV-1-infected, or vaccinated but uninfected, Eqca-1*00101-positive horses were used in IFN-γ enzyme-linked immunospot (ELISPOT) assays. When we screened the 87 Eqca-1*00101-binding peptides for T cell reactivity, only one Eqca-1*00101 epitope, derived from the intermediate-early protein ICP4, was identified. Thus, despite its common occurrence in several horse breeds, Eqca-1*00101 is associated with a narrow binding repertoire and a similarly narrow T cell response to an important equine viral pathogen. Intriguingly, these features are shared with other human and macaque major histocompatibility complex (MHC) molecules with a similar specificity for D in position 2 or 3 in their main anchor motif.
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Affiliation(s)
- Tobias Bergmann
- Institut für Virologie, Freie Universtiät Berlin, 14163, Berlin, Germany
| | - Carrie Moore
- Department of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA, 92037, USA
| | - John Sidney
- Department of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA, 92037, USA
| | - Donald Miller
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Rebecca Tallmadge
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Rebecca M Harman
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Carla Oseroff
- Department of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA, 92037, USA
| | - Amanda Wriston
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA
| | - Jeffrey Shabanowitz
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA
| | - Donald F Hunt
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA.,Department of Pathology, University of Virginia, Charlottesville, VA, 22904, USA
| | | | - Bjoern Peters
- Department of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA, 92037, USA
| | - Douglas F Antczak
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Alessandro Sette
- Department of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA, 92037, USA.
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Lau Q, Griffith JE, Higgins DP. Identification of MHCII variants associated with chlamydial disease in the koala (Phascolarctos cinereus). PeerJ 2014; 2:e443. [PMID: 25024912 PMCID: PMC4081129 DOI: 10.7717/peerj.443] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 06/02/2014] [Indexed: 01/19/2023] Open
Abstract
Chlamydiosis, the most common infectious disease in koalas, can cause chronic urogenital tract fibrosis and infertility. High titres of serum immunoglobulin G against 10 kDa and 60 kDa chlamydial heat-shock proteins (c-hsp10 and c-hsp60) are associated with fibrous occlusion of the koala uterus and uterine tube. Murine and human studies have identified associations between specific major histocompatibility complex class II (MHCII) alleles or genotypes, and higher c-hsp 60 antibody levels or chlamydia-associated disease and infertility. In this study, we characterised partial MHCII DAB and DBB genes in female koalas (n = 94) from a single geographic population, and investigated associations among antibody responses to c-hsp60 quantified by ELISA, susceptibility to chlamydial infection, or age. The identification of three candidate MHCII variants provides additional support for the functional role of MHCII in the koala, and will inform more focused future studies. This is the first study to investigate an association between MHC genes with chlamydial pathogenesis in a non-model, free-ranging species.
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Affiliation(s)
- Quintin Lau
- Faculty of Veterinary Science, The University of Sydney , NSW , Australia
| | - Joanna E Griffith
- Faculty of Veterinary Science, The University of Sydney , NSW , Australia
| | - Damien P Higgins
- Faculty of Veterinary Science, The University of Sydney , NSW , Australia
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5
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Kydd JH, Case R, Minke J, Audonnet JC, Wagner B, Antczak DF. Immediate-early protein of equid herpesvirus type 1 as a target for cytotoxic T-lymphocytes in the Thoroughbred horse. J Gen Virol 2014; 95:1783-1789. [PMID: 24836672 DOI: 10.1099/vir.0.065888-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Cytotoxic T-lymphocytes (CTLs) are associated with protective immunity against disease caused by equid herpesvirus type 1 (EHV-1). However, the EHV-1 target proteins for CTLs are poorly defined. This limits the development of vaccine candidates designed to stimulate strong CTL immunity. Here, classical CTL assays using lymphocytes from horses of three defined MHC class I types that experienced natural infection with EHV-1 and a modified vaccinia virus construct containing an EHV-1 gene encoding the immediate-early (IE) protein are reported. Horses homozygous for the equine leukocyte antigen (ELA)-A2 haplotype, but not the ELA-A5 haplotype, produced MHC-restricted CTL responses against the IE protein. Previously, horses homozygous for the ELA-A3 haplotype also mounted CTL responses against the IE protein. Both haplotypes are common in major horse breeds, including the Thoroughbred. Thus, the IE protein is an attractive candidate molecule for future studies of T-cell immunity to EHV-1 in the horse.
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Affiliation(s)
- Julia H Kydd
- Animal Health Trust, Lanwades Park, Kennett, Newmarket, Suffolk CB8 7UU, UK
| | - Ruth Case
- Animal Health Trust, Lanwades Park, Kennett, Newmarket, Suffolk CB8 7UU, UK
| | - Julius Minke
- Merial SAS, R&D, 254 rue Marcel Merieux, Lyon, France
| | | | - Bettina Wagner
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, NY 14853, USA
| | - Douglas F Antczak
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, NY 14853, USA
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The determination of in vivo envelope-specific cell-mediated immune responses in equine infectious anemia virus-infected ponies. Vet Immunol Immunopathol 2012; 148:302-10. [PMID: 22795699 DOI: 10.1016/j.vetimm.2012.06.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Revised: 06/15/2012] [Accepted: 06/18/2012] [Indexed: 11/24/2022]
Abstract
Distinct from human lentivirus infection, equine infectious anemia virus (EIAV)-infected horses will eventually enter an inapparent carrier state in which virus replication is apparently controlled by adaptive immune responses. Although recrudescence of disease can occur after immune suppression, the actual immune correlate associated with protection has yet to be determined. Therefore, EIAV provides a model for investigating immune-mediated protective mechanisms against lentivirus infection. Here, we have developed a method to monitor EIAV-envelope specific cellular immunity in vivo. An EIA carrier horse with no clinical signs infected 7 years ago and 4 related experimental ponies infected 6 months previously were used in this study. Forty-four 20-mer peptides, representing the entire surface unit protein (gp90) of EIAV, were combined into 14 peptide pools and intradermally injected into the neck of EIAV-infected horses. An identical volume of saline alone was injected into a fifteenth site as a negative control. After 48 h, those sites with palpable infiltrations were measured prior to the collection of 2mm and 4mm punch biopsies. Total RNA was extracted from each 2mm biopsy for determination of CD3 and interferon-γ (IFN-γ) mRNA expression by real-time PCR. The 4mm skin biopsies were formalin-fixed and paraffin-embedded for immunohistochemistry (IHC) staining for CD3, CD20, CD25 and MAC387 (macrophage marker). Peripheral blood mononuclear cells (PBMC) were obtained prior to the injection and tested for in vitro reactivity against the same peptides. Histological examination showed that some of the envelope peptides elicited a lymphocytic cellular infiltration at the injection site, as evidenced by positive staining for CD3. Gp90 peptide-specific increases in CD3 and IFN-γ gene expression were also detected in the injection sites. Furthermore, differences were found between in vivo and in vitro responses to gp90 specific peptides. These results demonstrate a novel method for detecting in vivo cell-mediated immune responses to EIAV-specific peptides that is readily applicable to other host/pathogen systems.
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7
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Yao S, Qi J, Liu J, Chen R, Pan X, Li X, Gao F, Xia C. Expression, refolding and preliminary X-ray crystallographic analysis of equine MHC class I molecule complexed with an EIAV-Env CTL epitope. Acta Crystallogr Sect F Struct Biol Cryst Commun 2012; 68:20-3. [PMID: 22232164 PMCID: PMC3253827 DOI: 10.1107/s1744309111038139] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 09/18/2011] [Indexed: 05/31/2023]
Abstract
In order to clarify the structure and the peptide-presentation characteristics of the equine major histocompatibility complex (MHC) class I molecule, a complex of equine MHC class I molecule (ELA-A1 haplotype, 7-6 allele) with mouse β(2)-microglobulin and the cytotoxic T lymphocyte (CTL) epitope Env-RW12 (RVEDVTNTAEYW) derived from equine infectious anaemia virus (EIAV) envelope protein (residues 195-206) was refolded and crystallized. The crystal, which belonged to space group P2(1), diffracted to 2.3 Å resolution and had unit-cell parameters a = 82.5, b = 71.4, c = 99.8 Å, β = 102.9°. The crystal structure contained two molecules in the asymmetric unit. These results should help to determine the first equine MHC class I molecule structure presenting an EIAV CTL epitope.
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MESH Headings
- Amino Acid Sequence
- Animals
- Crystallography, X-Ray
- Epitopes, T-Lymphocyte/chemistry
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/metabolism
- Gene Expression
- Gene Products, env/chemistry
- Gene Products, env/immunology
- Histocompatibility Antigens Class I/chemistry
- Histocompatibility Antigens Class I/immunology
- Histocompatibility Antigens Class I/metabolism
- Horses/immunology
- Horses/metabolism
- Infectious Anemia Virus, Equine/chemistry
- Infectious Anemia Virus, Equine/immunology
- Molecular Sequence Data
- Protein Folding
- T-Lymphocytes, Cytotoxic/chemistry
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/metabolism
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Affiliation(s)
- Shugang Yao
- Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xi Lu No. 2, Haidian District, Beijing 100094, People’s Republic of China
| | - Jianxun Qi
- CAS Key Laboratory of Pathogenic Microbiology and Immunology (CASPMI), Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, People’s Republic of China
| | - Jun Liu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology (CASPMI), Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, People’s Republic of China
- Section of Digestive Diseases, Department of Internal Medicine, School of Medicine, Yale University, New Haven, CT 06520, USA
| | - Rong Chen
- Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xi Lu No. 2, Haidian District, Beijing 100094, People’s Republic of China
| | - Xiaocheng Pan
- Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xi Lu No. 2, Haidian District, Beijing 100094, People’s Republic of China
| | - Xiaoying Li
- Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xi Lu No. 2, Haidian District, Beijing 100094, People’s Republic of China
| | - Feng Gao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences (CAS), Beijing 100101, People’s Republic of China
| | - Chun Xia
- Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xi Lu No. 2, Haidian District, Beijing 100094, People’s Republic of China
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Development of a DNA microarray for detection of expressed equine classical MHC class I sequences in a defined population. Immunogenetics 2010; 62:633-9. [PMID: 20683590 DOI: 10.1007/s00251-010-0463-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Accepted: 06/28/2010] [Indexed: 10/19/2022]
Abstract
Development of an accurate and efficient molecular-based equine MHC class I typing method would facilitate the study of T lymphocyte immune responses in horses. Here, a DNA microarray was designed to detect expressed classical MHC class I genes comprising serologically defined equine leukocyte antigen (ELA)-A haplotypes represented in a closed Arabian horse breeding herd. Initially, cloning and sequencing of RT-PCR products were used to identify sequences associated with the ELA-A1, A4, and W11 haplotypes, and one undefined haplotype, in six horses. Subsequently, sequence-specific, conserved (positive control), and random nucleotide (negative control) 23- to 27-mer oligonucleotide microarray probes were designed and spotted onto an epoxy-coated masked slide using a robotic arrayer. Bulk RT-PCR products from each horse were biotinylated by nick translation, hybridized to the array, and detected using tyramide signal amplification. The microarray consistently detected eight of nine classical MHC class I transcripts and allowed ELA haplotypic associations to be made. Cloning and sequencing of RT-PCR products were then performed in a group of ELA disparate horses and ponies, in which six novel sequences were identified. This group was used to determine the specificity of the array. Overall, the microarray was more efficient than cloning and sequencing for detecting expressed classical MHC class I sequences in this defined population of horses, and was significantly more specific than serology. These results confirmed the utility of a microarray-based method for high-resolution MHC class I typing in the horse. With additional probes the array could be useful in a broader population.
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Tallmadge RL, Campbell JA, Miller DC, Antczak DF. Analysis of MHC class I genes across horse MHC haplotypes. Immunogenetics 2010; 62:159-72. [PMID: 20099063 DOI: 10.1007/s00251-009-0420-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2009] [Accepted: 12/12/2009] [Indexed: 11/28/2022]
Abstract
The genomic sequences of 15 horse major histocompatibility complex (MHC) class I genes and a collection of MHC class I homozygous horses of five different haplotypes were used to investigate the genomic structure and polymorphism of the equine MHC. A combination of conserved and locus-specific primers was used to amplify horse MHC class I genes with classical and nonclassical characteristics. Multiple clones from each haplotype identified three to five classical sequences per homozygous animal and two to three nonclassical sequences. Phylogenetic analysis was applied to these sequences, and groups were identified which appear to be allelic series, but some sequences were left ungrouped. Sequences determined from MHC class I heterozygous horses and previously described MHC class I sequences were then added, representing a total of ten horse MHC haplotypes. These results were consistent with those obtained from the MHC homozygous horses alone, and 30 classical sequences were assigned to four previously confirmed loci and three new provisional loci. The nonclassical genes had few alleles and the classical genes had higher levels of allelic polymorphism. Alleles for two classical loci with the expected pattern of polymorphism were found in the majority of haplotypes tested, but alleles at two other commonly detected loci had more variation outside of the hypervariable region than within. Our data indicate that the equine major histocompatibility complex is characterized by variation in the complement of class I genes expressed in different haplotypes in addition to the expected allelic polymorphism within loci.
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Affiliation(s)
- Rebecca L Tallmadge
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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10
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Mealey RH, Leib SR, Littke MH, Wagner B, Horohov DW, McGuire TC. Viral load and clinical disease enhancement associated with a lentivirus cytotoxic T lymphocyte vaccine regimen. Vaccine 2009; 27:2453-68. [PMID: 19368787 DOI: 10.1016/j.vaccine.2009.02.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 02/04/2009] [Accepted: 02/18/2009] [Indexed: 10/21/2022]
Abstract
Effective DNA-based vaccines against lentiviruses will likely induce CTL against conserved viral proteins. Equine infectious anemia virus (EIAV) infects horses worldwide, and serves as a useful model for lentiviral immune control. Although attenuated live EIAV vaccines have induced protective immune responses, DNA-based vaccines have not. In particular, DNA-based vaccines have had limited success in inducing CTL responses against intracellular pathogens in the horse. We hypothesized that priming with a codon-optimized plasmid encoding EIAV Gag p15/p26 with co-administration of a plasmid encoding an equine IL-2/IgG fusion protein as a molecular adjuvant, followed by boosting with a vaccinia vector expressing Gag p15/p26, would induce protective Gag-specific CTL responses. Although the regimen induced Gag-specific CTL in four of seven vaccinated horses, CTL were not detected until after the vaccinia boost, and protective effects were not observed in EIAV challenged vaccinates. Unexpectedly, vaccinates had significantly higher viral loads and more severe clinical disease, associated with the presence of vaccine-induced CTL. It was concluded that (1) further optimization of the timing and route of DNA immunization was needed for efficient CTL priming in vivo, (2) co-administration of the IL-2/IgG plasmid did not enhance CTL priming by the Gag p15/p26 plasmid, (3) vaccinia vectors are useful for lentivirus-specific CTL induction in the horse, (4) Gag-specific CTL alone are either insufficient or a more robust Gag-specific CTL response is needed to limit EIAV viremia and clinical disease, and (5) CTL-inducing vaccines lacking envelope immunogens can result in lentiviral disease enhancement. Although the mechanisms for enhancement associated with this vaccine regimen remain to be elucidated, these results have important implications for development of lentivirus T cell vaccines.
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Affiliation(s)
- Robert H Mealey
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, 99164-7040, United States.
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11
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Draper LA, Grainger K, Deegan LH, Cotter PD, Hill C, Ross RP. Cross-immunity and immune mimicry as mechanisms of resistance to the lantibiotic lacticin 3147. Mol Microbiol 2009; 71:1043-54. [PMID: 19183281 DOI: 10.1111/j.1365-2958.2008.06590.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Lantibiotics are antimicrobial peptides that possess great potential as clinical therapeutic agents. These peptides exhibit many beneficial traits and in many cases the emergence of resistance is extremely rare. In contrast, producers of lantibiotics synthesize dedicated immunity proteins to provide self-protection. These proteins have very specific activities and cross-immunity is rare. However, producers of two peptide lantibiotics, such as lacticin 3147, face the unusual challenge of exposure to two active peptides (alpha and beta). Here, in addition to establishing the contribution of LtnI and LtnFE to lacticin 3147 immunity, investigations were carried out to determine if production of a closely related lantibiotic (i.e. staphylococcin C55) or possession of LtnI/LtnFE homologues could provide protection. Here we establish that not only are staphylococcin C55 producers cross-immune to lacticin 3147, and therefore represent a natural repository of Staphylococcus aureus strains that are protected against lacticin 3147, but that functional immunity homologues are also produced by strains of Bacillus licheniformis and Enterococcus faecium. This result raises the spectre of resistance through immune mimicry, i.e. the emergence of lantibiotic-resistant strains from the environment resulting from the possession/acquisition of immunity gene homologues. These phenomena will have to be considered carefully when developing lantibiotics for clinical application.
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12
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Mealey RH, Littke MH, Leib SR, Davis WC, McGuire TC. Failure of low-dose recombinant human IL-2 to support the survival of virus-specific CTL clones infused into severe combined immunodeficient foals: lack of correlation between in vitro activity and in vivo efficacy. Vet Immunol Immunopathol 2008; 121:8-22. [PMID: 17727961 PMCID: PMC2967287 DOI: 10.1016/j.vetimm.2007.07.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2007] [Revised: 06/24/2007] [Accepted: 07/11/2007] [Indexed: 01/08/2023]
Abstract
Although CTL are important for control of lentiviruses, including equine infectious anemia virus (EIAV), it is not known if CTL can limit lentiviral replication in the absence of CD4 help and neutralizing antibody. Adoptive transfer of EIAV-specific CTL clones into severe combined immunodeficient (SCID) foals could resolve this issue, but it is not known whether exogenous IL-2 administration is sufficient to support the engraftment and proliferation of CTL clones infused into immunodeficient horses. To address this question we adoptively transferred EIAV Rev-specific CTL clones into four EIAV-challenged SCID foals, concurrent with low-dose aldesleukin (180,000U/m2), a modified recombinant human IL-2 (rhuIL-2) product. The dose was calculated based on the specific activity on equine PBMC in vitro, and resulted in plasma concentrations considered sufficient to saturate high affinity IL-2 receptors in humans. Despite specific activity on equine PBMC that was equivalent to recombinant equine IL-2 and another form of rhuIL-2, aldesleukin did not support the engraftment and expansion of infused CTL clones, and control of viral load and clinical disease did not occur. It was concluded that survival of Rev-specific CTL clones infused into EIAV-challenged SCID foals was not enhanced by aldesleukin at the doses used in this study, and that in vitro specific activity did not correlate with in vivo efficacy. Successful adoptive immunotherapy with CTL clones in immunodeficient horses will likely require higher doses of rhuIL-2, co-infusion of CD4+ T lymphocytes, or administration of equine IL-2.
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Affiliation(s)
- Robert H Mealey
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington 99164-7040, United States.
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13
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Mealey RH, Littke MH, Leib SR, Davis WC, McGuire TC. Cloning and large-scale expansion of epitope-specific equine cytotoxic T lymphocytes using an anti-equine CD3 monoclonal antibody and human recombinant IL-2. Vet Immunol Immunopathol 2007; 118:121-8. [PMID: 17498813 PMCID: PMC2002571 DOI: 10.1016/j.vetimm.2007.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2007] [Revised: 03/20/2007] [Accepted: 04/05/2007] [Indexed: 11/20/2022]
Abstract
Cytotoxic T lymphocytes are involved in controlling intracellular pathogens in many species, including horses. Particularly, CTL are critical for the control of equine infectious anemia virus (EIAV), a lentivirus that infects horses world-wide. In humans and animal models, CTL clones are valuable for evaluating the fine specificity of epitope recognition, and for adoptive immunotherapy against infectious and neoplastic diseases. Cloned CTL would be equally useful for similar studies in the horse. Here we present the first analysis of a method to generate equine CTL clones. Peripheral blood mononuclear cells were obtained from an EIAV-infected horse and stimulated with the EIAV Rev-QW11 peptide. Sorted CD8+ T cells were cloned by limiting dilution, and expanded without further antigen addition using irradiated PBMC, anti-equine CD3, and human recombinant IL-2. Clones could be frozen and thawed without detrimental effects, and could be subsequently expanded to numbers exceeding 2 x 10(9)cells. Flow cytometry of expanded clones confirmed the CD3+/CD8+ phenotype, and chromium release assays confirmed CTL activity. Finally, sequencing TCR beta chain genes confirmed clonality. Our results provide a reliable means to generate large numbers of epitope-specific equine CTL clones that are suitable for use in downstream applications, including functional assays and adoptive transfer studies.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/immunology
- CD3 Complex/immunology
- Clone Cells/cytology
- Clone Cells/drug effects
- Epitopes, T-Lymphocyte/immunology
- Horses/immunology
- Humans
- Interleukin-2/immunology
- Interleukin-2/pharmacology
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Recombinant Proteins
- T-Lymphocytes, Cytotoxic/cytology
- T-Lymphocytes, Cytotoxic/drug effects
- T-Lymphocytes, Cytotoxic/immunology
- Time Factors
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Affiliation(s)
- Robert H Mealey
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA.
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