title: A viral long terminal repeat expressed in CD4+CD8+ precursors is downregulated in mature peripheral CD4-CD8+ or CD4+CD8- T cells.
abstract: The long terminal repeat from a thymotropic mouse mammary tumor virus variant, DMBA-LV, was used to drive the expression of two reporter genes, murine c-myc and human CD4, in transgenic mice. Expression was observed specifically in thymic immature cells. Expression of c-myc in these cells induced oligoclonal CD4+ CD8+ T-cell thymomas. Expression of human CD4 was restricted to thymic progenitor CD4- CD8- and CD4+ CD8+ T cells and was shut off in mature CD4+ CD8- and CD4- CD8+ T cells, known to be derived from the progenitor double-positive T cells. These results suggest the existence of similar and common factors in CD4+ CD8- and CD4- CD8+ T cells and support a model of differentiation of CD4+ CD8+ T cells through common signal(s) involved in turning off the expression of the CD4 or CD8 gene.
authors.affiliation: Laboratory of Molecular Biology, Clinical Research Institute of Montreal, Quebec, Canada.
authors.forename: Y
authors.initials: Y
authors.lastname: Paquette
authors.forename: L
authors.initials: L
authors.lastname: Doyon
authors.forename: A
authors.initials: A
authors.lastname: Laperrière
authors.forename: Z
authors.initials: Z
authors.lastname: Hanna
authors.forename: J
authors.initials: J
authors.lastname: Ball
authors.forename: R P
authors.initials: RP
authors.lastname: Sekaly
authors.forename: P
authors.initials: P
authors.lastname: Jolicoeur
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D016375:Antisense Elements (Genetics); D015704:CD4 Antigens / Q000235:genetics* / Q000276:immunology*; D016827:CD8 Antigens / Q000276:immunology*; D005434:Flow Cytometry; D016259:Genes, myc; D006801:Humans; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics*; D051379:Mice; D008819:Mice, Nude; D008822:Mice, Transgenic; D010641:Phenotype; D015347:RNA Probes; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D013945:Thymoma / Q000235:genetics / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology; D013953:Thymus Neoplasms / Q000235:genetics / Q000276:immunology; D014158:Transcription, Genetic
chemical_list: D000911:Antibodies, Monoclonal; D016375:Antisense Elements (Genetics); D015704:CD4 Antigens; D016827:CD8 Antigens; D015347:RNA Probes