title: Emergence of double-positive CD4/CD8 cells from adult peripheral blood mononuclear cells infected with human T cell leukemia virus type I (HTLV-I).
abstract: It is known that the human T lymphotropic retrovirus type I (HTLV-I) preferentially selects lymphocytes expressing the CD4 phenotype in vivo and in vitro. The present study shows that the emergence of double-positive (DP) CD4/CD8 cells was a constant, even if transient, phenomenon occurring in early phases after the in vitro HTLV-I infection of adult human peripheral blood mononuclear cells (PBMC). Moreover, purified CD8+ lymphocytes, isolated from human PBMC after challenge with HTLV-I, gave origin to a relatively stable DP CD4/CD8 cell line after a few weeks in culture. Conversely, isolated CD4+ T lymphocytes did not show DP emergence during either the early phases of HTLV-I infection or long-term culture. One of the DP cell lines was maintained in culture for more than 1 year and was characterized on the basis of virological and phenotypic features. This cell line bore HTLV-I sequences as demonstrated by PCR analysis, and 60-90% of the DP cells expressed the virus core protein p19. In addition the phenotype of this DP cell line infected with HTLV-I highly expressed antigens associated to activation such as CD45R0, CD18, and CD54.
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Rome Tor Vergata, Italy.
authors.forename: B
authors.initials: B
authors.lastname: Macchi
authors.forename: G
authors.initials: G
authors.lastname: Graziani
authors.forename: J
authors.initials: J
authors.lastname: Zhang
authors.forename: A
authors.initials: A
authors.lastname: Mastino
mesh_terms: D015703:Antigens, CD / Q000096:biosynthesis; D018821:CD18 Antigens; D015704:CD4 Antigens / Q000276:immunology*; D016827:CD8 Antigens / Q000276:immunology*; D015815:Cell Adhesion Molecules / Q000096:biosynthesis; D002454:Cell Differentiation / Q000276:immunology; D002460:Cell Line / Q000276:immunology; D002478:Cells, Cultured / Q000276:immunology; D015490:HTLV-I Infections / Q000276:immunology*; D006801:Humans; D066298:In Vitro Techniques; D018799:Intercellular Adhesion Molecule-1; D017493:Leukocyte Common Antigens / Q000096:biosynthesis; D009000:Monocytes / Q000276:immunology*; D014758:Viral Core Proteins / Q000096:biosynthesis
chemical_list: D015703:Antigens, CD; D018821:CD18 Antigens; D015704:CD4 Antigens; D016827:CD8 Antigens; D015815:Cell Adhesion Molecules; D014758:Viral Core Proteins; D018799:Intercellular Adhesion Molecule-1; D017493:Leukocyte Common Antigens