title: Relation of GIX antigen of thymocytes to envelope glycoprotein of murine leukemia virus.
abstract: Expression of Gix surface antigen on thymocytes is an inherited mendelian train of certain strains of mice. We report here the following new findings: (a) Gix antigen was found free in the serum of Gix+ mouse strains. (b) Expression vs. nonexpression of Gix antigen was invariably correlated with presence or absence of the group-specific antigen of Murine leukemia virus (MuLV) gp69/71 in the serum of mice of inbred and segregating populations. (c) Gix antigen could be removed from normal Gix+ mouse serum by precipitation with antiserum to MuLV gp 69/71. (d) Anti-gp69/71 serum was weakly cytotoxic for Gix+ thymocytes, and partially blocked the cytotoxic activity of Gix antibody for Gix+ thymocytes. (e) Purified AKR virus absorbed Gix activity, and disruption of the virions did not increase their absorbing capacity. These serological data indicate that Gix antigen is a constituent of gp69/71, the glycoprotein which is the major component of the MuLV envelope. On present evidence, Gix antigen is represented in intact virions and is probably accessible to Gix antibody.
mesh_terms: D000042:Absorption; D000818:Animals; D000906:Antibodies; D000914:Antibodies, Viral / Q000032:analysis; D000956:Antigens, Viral / Q000032:analysis*; D002462:Cell Membrane / Q000276:immunology; D003165:Complement System Proteins; D003601:Cytotoxicity Tests, Immunologic; D000939:Epitopes; D005455:Fluorescent Antibody Technique; D005838:Genotype; D006023:Glycoproteins / Q000276:immunology*; D007106:Immune Sera; D007519:Isoantigens / Q000032:analysis*; D009052:Leukemia Virus, Murine / Q000276:immunology*; D051379:Mice; D008815:Mice, Inbred Strains; D008967:Molecular Biology; D010641:Phenotype; D013601:T-Lymphocytes / Q000276:immunology*; D014764:Viral Proteins / Q000032:analysis*
chemical_list: D000906:Antibodies; D000914:Antibodies, Viral; D000956:Antigens, Viral; D000939:Epitopes; D006023:Glycoproteins; D007106:Immune Sera; D007519:Isoantigens; D014764:Viral Proteins; D003165:Complement System Proteins