title: Alpha1/alpha2 domains of H-2D(d), but not H-2L(d), induce "missing self" reactivity in vivo--no effect of H-2L(d) on protection against NK cells expressing the inhibitory receptor Ly49G2.
abstract: Introduction of the MHC class I transgene H-2Dd on C57BL/6 (B6) background conveys NK cell-mediated "missing self" reactivity against transgene-negative cells, and down-regulates expression of the inhibitory receptors Ly49A and Ly49G2 in NK cells. We here present an analysis of transgenic mice expressing chimeric H-2Dd/Ld MHC class I transgenes, and show that the alpha1/alpha2 domains of H-2Dd were necessary and sufficient to induce "missing self" recognition and to down-modulate Ly49A and Ly49G2 receptors. In contrast, transgenes containing the alpha1/alpha2 domains of H-2Ld induced none of these changes, suggesting that not all MHC class I alleles in a host necessarily take part in NK cell education. The lack of effect of the alpha1/alpha2 domains of H-2Ld on NK cell specificity was surprising, considering that both H-2Ld and H-2Dd have been reported to interact with Ly49G2. Therefore, the role of H-2Ld for protection against NK cells expressing Ly49G2 was re-investigated in a transfection system. In contradiction to earlier reports, we show that H-2Dd, but not H-2Ld, abolished killing by sorted Ly49G2+ NK cells, indicating that H-2Ld does not inhibit NK cells via the Ly49G2 receptor.
authors.affiliation: Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden.
authors.forename: M H
authors.initials: MH
authors.lastname: Johansson
authors.forename: E
authors.initials: E
authors.lastname: Höglund
authors.forename: M C
authors.initials: MC
authors.lastname: Nakamura
authors.forename: J C
authors.initials: JC
authors.lastname: Ryan
authors.forename: P
authors.initials: P
authors.lastname: Höglund
mesh_terms: D000818:Animals; D000950:Antigens, Ly; D003602:Cytotoxicity, Immunologic; D006183:H-2 Antigens / Q000235:genetics / Q000276:immunology*; D064532:Histocompatibility Antigen H-2D; D007694:Killer Cells, Natural / Q000276:immunology*; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D055650:NK Cell Lectin-Like Receptor Subfamily A; D011971:Receptors, Immunologic / Q000235:genetics / Q000276:immunology*; D055630:Receptors, NK Cell Lectin-Like; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology
chemical_list: D000950:Antigens, Ly; D006183:H-2 Antigens; D064532:Histocompatibility Antigen H-2D; C527088:Klra1 protein, mouse; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins; D055650:NK Cell Lectin-Like Receptor Subfamily A; D011971:Receptors, Immunologic; D055630:Receptors, NK Cell Lectin-Like; D011993:Recombinant Fusion Proteins