title: MHC class Ia-restricted memory T cells inhibit expansion of a nonprotective MHC class Ib (H2-M3)-restricted memory response.
abstract: Listeria monocytogenes infection generates major histocompatibility complex (MHC) class Ia-restricted and MHC class Ib-(H2-M3)-restricted effector and memory CD8+ T cells. However, only MHC class Ia-restricted memory cells expand after rechallenge, and it is unknown if MHC class Ib-restricted memory CD8+ T cells generated by vaccination are protective. We show here that H2-M3-restricted memory CD8+ T cells were capable of secondary expansion but, in contrast to primary H2-M3-restricted effector cells, failed to provide protective immunity. In lm-immune mice, MHC class Ia-restricted memory CD8+ T cells prevented the expansion of H2-M3-restricted memory T cell populations by limiting dendritic cell antigen presentation. Thus, protective immunity by H2-M3-restricted T cells is limited to primary infection, indicating that memory MHC class Ia-restricted T cells prevent nonessential immune responses during secondary infection.
authors.affiliation: Interdisciplinary Program in Immunology, The University of Iowa, Iowa City, IA 52242, USA.
authors.forename: Sara E
authors.initials: SE
authors.lastname: Hamilton
authors.forename: Brandon B
authors.initials: BB
authors.lastname: Porter
authors.forename: Kelly A Nordyke
authors.initials: KA
authors.lastname: Messingham
authors.forename: Vladimir P
authors.initials: VP
authors.lastname: Badovinac
authors.forename: John T
authors.initials: JT
authors.lastname: Harty
mesh_terms: D000818:Animals; D017951:Antigen Presentation; D000942:Antigens, Bacterial / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000276:immunology; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D007156:Immunologic Memory; D008089:Listeria monocytogenes / Q000276:immunology; D008088:Listeriosis / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D008822:Mice, Transgenic
chemical_list: D000942:Antigens, Bacterial; D015395:Histocompatibility Antigens Class I