title: Cutting Edge: Epitope-dependent effect of Nef-mediated HLA class I down-regulation on ability of HIV-1-specific CTLs to suppress HIV-1 replication.
abstract: It is believed that Nef-mediated HLA class I down-regulation is one of the mechanisms that allow HIV-1-infected cells to escape from being killed by HIV-1-specific human CTLs. In this study, we show that the effect of Nef-mediated HLA class I down-regulation on the ability of HIV-1-specific CTLs to suppress HIV-1 replication is epitope dependent. The CTLs specific for two Pol epitopes presented by HLA-B*5101, one of the HLA alleles associated with slow progression to AIDS, effectively killed HIV-1-infected CD4+ T cells and suppressed HIV-1 replication. In contrast, those specific for the other four epitopes failed to kill HIV-1-infected CD4+ T cells and partially or hardly suppressed HIV-1 replication. The difference of the ability between these two types of CTLs may result from the difference of the number of HLA class I epitope complex on the surface of NL-432-infected CD4+ T cells.
authors.affiliation: Division of Viral Immunology, Center for AIDS Research, Kumamoto University, 2-2-2 Honjo, Kumamoto 860-0811, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Tomiyama
authors.forename: Mamoru
authors.initials: M
authors.lastname: Fujiwara
authors.forename: Shinichi
authors.initials: S
authors.lastname: Oka
authors.forename: Masafumi
authors.initials: M
authors.lastname: Takiguchi
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D015536:Down-Regulation; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D005434:Flow Cytometry; D015693:Gene Products, nef / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology* / Q000502:physiology; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D006801:Humans; D066298:In Vitro Techniques; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014779:Virus Replication / Q000276:immunology; D054311:nef Gene Products, Human Immunodeficiency Virus
chemical_list: D018984:Epitopes, T-Lymphocyte; D015693:Gene Products, nef; D015395:Histocompatibility Antigens Class I; D054311:nef Gene Products, Human Immunodeficiency Virus