title: Differential expression of the human Thy-1 gene in rodent-human somatic cell hybrids [corrected].
abstract: Thy-1 is a cell surface differentiation marker which shows distinct patterns of tissue-specific expression in different species. In man, the Thy-1 antigen is encoded by chromosome 11. We have examined the regulatory signals determining human Thy-1 expression through serologic analysis of rodent-human somatic cell hybrids retaining human chromosome 11 in which the fusion partners belong to distinct differentiation lineages. Cell surface expression of human Thy-1 was determined by mixed hemadsorption assays with two monoclonal antibodies (mAb), K117 and L127, shown to detect authentic human Thy-1 through analysis of COS-7 monkey kidney cells transfected with a cloned human Thy-1 gene. Three different patterns of human Thy-1 expression were observed when hybrid cells, constructed with different human and rodent cell types, were tested with mAb K117 and L127. Hybrids formed between Thy-1+ human neuroblastoma cells and Thy-1- mouse neuroblastoma cells, or hybrids between Thy-1+ human fibroblasts and the Thy-1- mouse kidney carcinoma, RAG, retain human Thy-1 expression. In contrast, hybrids formed between either Thy-1+ human neuroblastoma cells or Thy-1+ human fibroblasts and Thy-1- mouse L cells lose expression of human Thy-1 even though chromosome 11 is retained. Finally, hybrids formed between Thy-1- human peripheral lymphocytes or a Thy-1- lymphoblastoid B cell line and Thy-1- Chinese hamster fibroblasts begin to express human Thy-1. These studies suggest that both positive and negative trans-acting signals may play a role in the tissue-specific regulation of the human Thy-1 gene.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000951:Antigens, Neoplasm / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D000954:Antigens, Surface / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D002522:Chlorocebus aethiops; D002880:Chromosomes, Human, Pair 11; D006224:Cricetinae; D003412:Cricetulus; D005786:Gene Expression Regulation; D006801:Humans; D006822:Hybrid Cells / Q000276:immunology*; D007739:L Cells / Q000276:immunology; D051379:Mice; D009447:Neuroblastoma / Q000473:pathology; D009928:Organ Specificity; D018800:Thy-1 Antigens
chemical_list: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D018800:Thy-1 Antigens