Immunodominance of a single CTL epitope in a primate species with limited MHC class I polymorphism.
MHC class I molecules play a crucial role in immunity to viral infections by presenting viral peptides to cytotoxic T lymphocytes. One of the hallmarks of MHC class I genes in outbred populations is their extraordinary polymorphism, yet the significance of this diversity is poorly understood. Certain species with reduced MHC class I diversity, such as the cotton-top tamarin (Saguinus oedipus), are more susceptible to fatal viral infections. To explore the relationship between this primate's limited MHC class I diversity and its susceptibility to viruses, we infected five cotton-top tamarins with influenza virus. Every tamarin recognized the same immunodominant CTL epitope of the influenza nucleoprotein. Surprisingly, this nucleoprotein peptide was bound by Saoe-G*08, an MHC class I molecule expressed by every cotton-top tamarin. Two tamarins also made a subdominant response to an epitope of the matrix (M1) protein. This peptide appeared to be bound by another common MHC class I molecule. With the exception of an additional subdominant response to the polymerase (PB2) protein in one individual, no other influenza-specific CTL responses were detected. In populations or species with limited MHC class I polymorphism like the cotton-top tamarin, a dependence on shared MHC class I molecules may enhance susceptibility to viral infection, since viruses that evade MHC class I-restricted recognition in one individual will likely evade recognition in the majority of individuals.
Evans
D T
DT
Wisconsin Regional Primate Research Center, University of Wisconsin, Madison 53715, USA.
Piekarczyk
M S
MS
Allen
T M
TM
Boyson
J E
JE
Yeager
M
M
Hughes
A L
AL
Gotch
F M
FM
Hinshaw
V S
VS
Watkins
D I
DI
D000818:Animals; D017951:Antigen Presentation; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002999:Clone Cells; D005805:Genes, MHC Class I / Q000276:immunology*; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D016056:Immunodominant Epitopes / Q000276:immunology* / Q000378:metabolism; D009980:Influenza A virus / Q000276:immunology; D009698:Nucleoproteins / Q000276:immunology; D009976:Orthomyxoviridae Infections / Q000276:immunology; D011110:Polymorphism, Genetic / Q000276:immunology*; D012324:RNA-Dependent RNA Polymerase; D016865:Reassortant Viruses / Q000276:immunology; D012452:Saguinus; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000378:metabolism; D014763:Viral Matrix Proteins / Q000276:immunology / Q000378:metabolism; D014764:Viral Proteins / Q000276:immunology
D015395:Histocompatibility Antigens Class I; D016056:Immunodominant Epitopes; C031540:M-protein, influenza virus; C488936:M1 protein, Influenza A virus; D009698:Nucleoproteins; C057027:PB2 protein, Influenzavirus A; D014763:Viral Matrix Proteins; D014764:Viral Proteins; D012324:RNA-Dependent RNA Polymerase