A viral long terminal repeat expressed in CD4+CD8+ precursors is downregulated in mature peripheral CD4-CD8+ or CD4+CD8- T cells.
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.
Paquette
Y
Y
Laboratory of Molecular Biology, Clinical Research Institute of Montreal, Quebec, Canada.
Doyon
L
L
Laperrière
A
A
Hanna
Z
Z
Ball
J
J
Sekaly
R P
RP
Jolicoeur
P
P
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
D000911:Antibodies, Monoclonal; D016375:Antisense Elements (Genetics); D015704:CD4 Antigens; D016827:CD8 Antigens; D015347:RNA Probes