title: Cutting edge: major CD8 T cell response to live bacillus Calmette-Guérin is mediated by CD1 molecules.
abstract: MHC class I-restricted CD8(+) T cells are a crucial component of the host defense against mycobacterial infection in mice, but it has often proved very difficult to identify the CD8 T cell response in humans. Human group 1 CD1 molecules (CD1a, -b, -c) mediate MHC-independent presentation of mycobacteria-derived lipid and glycolipid Ags to CD8(+) T cells, and their intracellular localization to the endocytic system may favor efficient monitoring of phagosome-resident mycobacteria. Here, we show that bacillus Calmette-Guérin (BCG)-immunized subjects contain a significant circulating pool of CD8(+) T cells that recognize BCG-infected DCs in a CD1-dependent, but MHC-independent, manner. These CD1-restricted T cells efficiently detected live, rather than dead, BCG and produced IFN-gamma, an important cytokine for protection against mycobacterial infection. These results emphasize that lipid-reactive CD8(+) T cells may contribute to host defense against mycobacterial infection.
authors.affiliation: Department of Microbiology and Immunology, Nippon Medical School, Tokyo, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Kawashima
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Norose
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Enomoto
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Narazaki
authors.forename: Eiji
authors.initials: E
authors.lastname: Watari
authors.forename: Shigeo
authors.initials: S
authors.lastname: Tanaka
authors.forename: Hidemi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Ikuya
authors.initials: I
authors.lastname: Yano
authors.forename: Michael B
authors.initials: MB
authors.lastname: Brenner
authors.forename: Masahiko
authors.initials: M
authors.lastname: Sugita
mesh_terms: D000328:Adult; D019138:Antibodies, Blocking / Q000494:pharmacology; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000382:microbiology; D018949:Antigens, CD1 / Q000097:blood / Q000276:immunology / Q000502:physiology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000382:microbiology*; D003713:Dendritic Cells / Q000276:immunology / Q000382:microbiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D019169:Jurkat Cells; D008297:Male; D009163:Mycobacterium bovis / Q000254:growth & development / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000382:microbiology
chemical_list: D019138:Antibodies, Blocking; D018949:Antigens, CD1; C419394:CD1b antigen; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II