title: Distinct regulation of H2-M3-restricted memory T cell responses in lymph node and spleen.
abstract: CD8 T cell populations restricted by H2-M3 MHC class Ib molecules expand rapidly during primary Listeria monocytogenes infection but only minimally upon reinfection. In contrast, CD8 T cells restricted by MHC class Ia molecules undergo more delayed expansion during primary infection but rapid and robust expansion following reinfection. In this study we demonstrate that primary H2-M3-restricted CD8 T cell responses are unaffected by the frequency of naive MHC class Ia-restricted T cells during L. monocytogenes infection. The magnitude of H2-M3-restricted memory responses, in contrast, is down-modulated by increasing frequencies of MHC class Ia-restricted effector T cells following secondary systemic infection. Suppression by MHC class Ia-restricted T cells, however, is not a universal feature of MHC class Ib-restricted memory responses. Primary systemic L. monocytogenes infection followed by secondary tissue infection, for example, results in robust expansion of H2-M3-restricted memory T cells in draining lymph nodes, despite the activation of MHC class Ia-restricted memory T cell responses. Thus, whereas MHC class Ia-restricted memory T cell populations predominate in spleens following systemic reinfection, H2-M3-restricted memory T cell responses remain prominent in lymph nodes draining localized infections. Our studies demonstrate that interactions between CD8 T cell populations can differ, depending on the status of the responding T cells (naive vs memory) and the route of reinfection. These results may have important implications for prime-boost vaccination strategies.
authors.affiliation: Infectious Diseases Service, Department of Medicine and Laboratory of Antimicrobial Immunity, Immunology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Ploss
authors.forename: Ingrid
authors.initials: I
authors.lastname: Leiner
authors.forename: Eric G
authors.initials: EG
authors.lastname: Pamer
mesh_terms: D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000276:immunology; D006183:H-2 Antigens / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007114:Immunization; D007156:Immunologic Memory; D008089:Listeria monocytogenes / Q000276:immunology; D008088:Listeriosis / Q000276:immunology; D008198:Lymph Nodes / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D013154:Spleen / Q000276:immunology*
chemical_list: D006183:H-2 Antigens; C032876:H-2Kb protein, mouse; C078177:H2-M3 antigen; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II