title: Independent regulation of H-2K and H-2D gene expression in murine teratocarcinoma somatic cell hybrids.
abstract: Cells of two teratocarcinoma stem cell lines (PCC4 azaguanine [aza] 1 and F9 5-bromodeoxyuridine [BrdU]) were fused with normal mouse spleen cells and mouse thymoma-derived cells (BW 5147), respectively. Hybrid clones were tested for the expression of molecules coded by the H-2K and -2D genes both by absorption analysis of conventional H-2 sera and by indirect antibody-binding radioimmunoassay with monoclonal antibodies. Somatic cell hybrids between PCC4 aza 1 and spleen cells morphologically resemble teratocarcinoma stem cells and do not express H-2 antigens. However, after differentiation in vitro, one of these hybrid clones expresses the H-2K and -2D gene products of both parental cell lines, one close expresses H-2-D- but not H-2K-coded antigenic determinants, and one clone remains H-2 negative. Somatic cell hybrids between F9 BrdU and BW 5147 resemble fibroblasts. Analysis of a series of hybrid clones revealed some clones that express both the H-2K- and H-2D-coded antigenic specificities of both parental alleles, some that express H-2D gene products strongly and the H-2K gene products very weakly, and some that express H-2D- but not H-2K-coded molecules. These results imply independent regulation of expression of the H-2K and -2D genes. The H-2D gene products appear to be preferentially expressed if the hybrid cells are capable of expressing H-2. The results suggest complex regulatory mechanisms that are H-2K and H-2D specific.
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D002454:Cell Differentiation; D002999:Clone Cells / Q000276:immunology; D005796:Genes; D006183:H-2 Antigens / Q000235:genetics*; D006822:Hybrid Cells / Q000276:immunology*; D007518:Isoantibodies; D008285:Major Histocompatibility Complex; D051379:Mice; D009374:Neoplasms, Experimental / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013724:Teratoma / Q000235:genetics / Q000276:immunology*
chemical_list: D006183:H-2 Antigens; D007518:Isoantibodies