title: Epitope-Specific Vaccination Limits Clonal Expansion of Heterologous Naive T Cells during Viral Challenge.
abstract: Despite robust secondary T cell expansion primed by vaccination, the impact on primary immune responses to heterotypic antigens remains undefined. Here we show that secondary expansion of epitope-specific memory CD8+T cells primed by prior infection with recombinant pathogens limits the primary expansion of naive CD8+T cells with specificity to new heterologous antigens, dampening protective immunity against subsequent pathogen challenge. The degree of naive T cell repression directly paralleled the magnitude of the recall response. Suppressed primary T cell priming reflects competition for antigen accessibility, since clonal expansion was not inhibited if the primary and secondary epitopes were expressed on different dendritic cells. Interestingly, robust recall responses did not impact antigen-specific NK cells, suggesting that adaptive and innate lymphocyte responses possess different activation requirements or occur in distinct anatomical locations. These findings have important implications in pathogen vaccination strategies that depend on the targeting of multiple T cell epitopes.
authors.affiliation: Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
authors.forename: Lexus R
authors.initials: LR
authors.lastname: Johnson
authors.affiliation: Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
authors.forename: Orr-El
authors.initials: OE
authors.lastname: Weizman
authors.affiliation: Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
authors.forename: Moritz
authors.initials: M
authors.lastname: Rapp
authors.affiliation: Division of Infectious Diseases, Cincinnati Children's Hospital, Cincinnati, OH 45229, USA.
authors.forename: Sing Sing
authors.initials: SS
authors.lastname: Way
authors.affiliation: Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Department of Immunology and Microbial Pathogenesis, Weill Cornell Medical College, New York, NY 10065, USA. Electronic address: sunj@mskcc.org.
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Sun
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000378:metabolism; D000941:Antigens / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D049109:Cell Proliferation; D002999:Clone Cells; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D008087:Listeria / Q000502:physiology; D051379:Mice; D018146:Muromegalovirus / Q000502:physiology*; D011995:Recombination, Genetic / Q000235:genetics; D013601:T-Lymphocytes / Q000276:immunology*; D014611:Vaccination
chemical_list: D000941:Antigens; D018984:Epitopes, T-Lymphocyte
keywords: CD8+ T cell; NK cell; antigen competition; antigen presenting cell; clonal expansion; mouse cytomegalovirus; recall response; recombinant Listeria monocytogenes; vaccination