title: [Fetomaternal tolerance: role of HLA-G molecule in the protection of the fetus against maternal natural killer activity].
abstract: HLA-G is a non-classical major histocompatibility complex class I molecule selectively expressed on extravillous trophoblast cells at the fetal-maternal interface. HLA-G may play an important role in maintaining maternal immune tolerance of the semi-allogenic fetus. In this study, we demonstrate for the first time the protective role of HLA-G during pregnancy. Indeed, cytotrophoblast cells of the fetus are resistant to lytic activity by maternal decidual natural killer cells. In order to precisely characterize the immunological functions of HLA-G products, we have investigated the protective role of the membrane-bound HLA-G1 and HLA-G2 isoforms against NK cell cytotoxicity. For this purpose, HLA-G1 and HLA-G2 cDNAs were transfected into the HLA-class I negative human K562 cell line. We demonstrate that both HLA-G1 and HLA-G2 transfectants inhibit NK cytolysis observed in peripheral blood from 25 donors (males and females). This led us to the conjecture that HLA-G is the public ligand for natural killer inhibitory receptors present in all individuals.
authors.affiliation: Service de recherches en hémato-immunologie, hôpital Saint-Louis, Paris, France.
authors.forename: N
authors.initials: N
authors.lastname: Rouas-Freiss
authors.forename: M
authors.initials: M
authors.lastname: Kirszenbaum
authors.forename: J
authors.initials: J
authors.lastname: Dausset
authors.forename: E D
authors.initials: ED
authors.lastname: Carosella
mesh_terms: D003602:Cytotoxicity, Immunologic; D005260:Female; D006680:HLA Antigens / Q000276:immunology*; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D006801:Humans; D007108:Immune Tolerance; D007112:Immunity, Maternally-Acquired; D007694:Killer Cells, Natural / Q000276:immunology*; D011247:Pregnancy; D014327:Trophoblasts / Q000276:immunology
chemical_list: D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I
vernacular_title: Tolérance foetomaternelle: rôle de la molécule HLA-G dans la protection du foetus contre l'activité natural killer maternelle.