title: Major histocompatibility complex class I-specific and -restricted killing of beta 2-microglobulin-deficient cells by CD8+ cytotoxic T lymphocytes.
abstract: Cytotoxic T lymphocytes (CTLs) recognize major histocompatibility complex (MHC) class I molecules, normally composed of a heavy chain, a beta 2-microglobulin (beta 2m), and peptide antigens. beta 2m is considered essential for the assembly and intracellular transport of MHC class I molecules as well as their peptide presentation to CTLs. Contrary to this dogma, we now report the generation of allospecific and restricted CD8+ and TCR alpha beta+ CTLs (where TCR is T-cell receptor) capable of killing beta 2m-deficient cells. Such CTLs were obtained by priming mice with live allogeneic beta 2m- spleen cells or mutant lymphoma cells producing MHC class I protein but no detectable beta 2m. Although both beta 2m- and beta 2m-expressing lymphoma cells were rejected in allogeneic mice, only the former were efficient inducers of CTLs recognizing beta 2m- cells. These CTLs were MHC class I (H-2Kb or Db)-specific and CD8-dependent and did not require serum as a source of external beta 2m in the culture. They could be induced across major and minor histocompatibility barriers. The H-2-restricted CTLs generated in the latter case failed to kill the antigen-processing-deficient target RMA-S cells. The results show that MHC class I heavy chains in beta 2m- cells can be transported to the cell surface and act as antigens or antigen-presenting molecules to allospecific and MHC-restricted CTLs.
authors.affiliation: Department of Tumor Biology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: R
authors.initials: R
authors.lastname: Glas
authors.forename: L
authors.initials: L
authors.lastname: Franksson
authors.forename: C
authors.initials: C
authors.lastname: Ohlén
authors.forename: P
authors.initials: P
authors.lastname: Höglund
authors.forename: B
authors.initials: B
authors.lastname: Koller
authors.forename: H G
authors.initials: HG
authors.lastname: Ljunggren
authors.forename: K
authors.initials: K
authors.lastname: Kärre
mesh_terms: D000818:Animals; D016827:CD8 Antigens / Q000032:analysis; D003602:Cytotoxicity, Immunologic; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D008285:Major Histocompatibility Complex; D051379:Mice; D008815:Mice, Inbred Strains; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D001613:beta 2-Microglobulin / Q000276:immunology*
chemical_list: D016827:CD8 Antigens; D015395:Histocompatibility Antigens Class I; D001613:beta 2-Microglobulin