title: Phenotypical and functional evaluation of CD8+/S6F1+ T lymphocytes in haemophiliac individuals with HIV-1 infection.
abstract: In this study we investigated the distribution of the S6F1 antigen, an epitope of the lymphocyte function-associated antigen, on CD8+ T lymphocytes in a series of 15 HIV-1+ and 20 HIV-1- haemophiliac patients. MoAbs recognizing the S6F1 antigen have been claimed to distinguish between killer effectors (brightly S6F1+ stained) and suppressor cells (dimly S6F1+ stained) within the CD8+ lymphoid population. In addition, we tried to find a correlation between the spontaneous in vitro immunoglobulin synthesis from patients' peripheral blood lymphocytes and the pattern of S6F1 expression. Although the total number of double-positive CD8+/S6F1+ cells was similar in both HIV-1+ and HIV-1- haemophiliac patients, a significant increase in the CD8+/S6F1+ population bright versus dim was documented in HIV-1-infected with respect to HIV-1- haemophiliacs (bright/dim ratio 3.97 +/- 0.61 versus 0.75 +/- 0.1, respectively, P < 0.005). This finding was correlated to a significant increase in spontaneous in vitro immunoglobulin production in HIV-1+ subjects compared with control haemophiliacs (P < 0.005). Purified CD8+ lymphocytes from HIV-1+ subjects showed a reduced suppressor activity on mitogen-induced immunoglobulin production. Taken together, these data suggest that HIV-1 infection favours the generation of CD8+/S6F1+ bright cells with putative cytotoxic-associated function, leading to a progressive reduction in the number of CD8+/S6F1+ dim suppressor lymphocytes. This phenomenon may contribute to the polyclonal hypergammaglobulinaemia present in HIV-1+ haemophiliac patients.
authors.affiliation: Centro Transfusionale, O.C. Castelfranco Veneto, Treviso, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Cavallin
authors.forename: A
authors.initials: A
authors.lastname: Traldi
authors.forename: R
authors.initials: R
authors.lastname: Zambello
mesh_terms: D000293:Adolescent; D000328:Adult; D016827:CD8 Antigens / Q000276:immunology*; D002478:Cells, Cultured; D005434:Flow Cytometry; D015658:HIV Infections / Q000276:immunology*; D006679:HIV Seropositivity / Q000276:immunology; D015497:HIV-1 / Q000276:immunology*; D006467:Hemophilia A / Q000276:immunology*; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis; D016130:Immunophenotyping; D016169:Lymphocyte Function-Associated Antigen-1 / Q000276:immunology*; D008934:Mitogens / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D016827:CD8 Antigens; D007136:Immunoglobulins; D016169:Lymphocyte Function-Associated Antigen-1; D008934:Mitogens