Plaeger-Marshall S, Hausner MA, Gudeman V, Smith D, Giorgi JV; International Conference on AIDS.

Int Conf AIDS. 1989 Jun 4-9; 5: 572 (abstract no. T.C.P.31).

UCLA School of Medicine, Los Angeles, CA, USA

OBJECTIVE: We previously have identified specific subsets of CD8 cells that increase in individuals with HIV infection. The present study was designed to characterize the function of CD8 subsets to determine their role in the immune response to HIV. METHODS: Subjects were 20-30 HIV seropositive (HM+) or seronegative (HM-) male homosexuals participating in the Los Angeles Multicenter AIDS Cohort Study, or healthy heterosexuals (HT). Monoclonal antibodies were directed against Leu7(HNK-1), and OKT10(CD38). Complement lysis was used to deplete cell subsets. Cytotoxic function was assessed by lectin-dependent cellular cytotoxicity (LDCC) employing Concanavalin A and 51 Cr-labelled CEM target cells in a 4 hour assay. RESULTS: Initial experiments showed that HM+ had elevated levels of LDCC (34+/-12% lysis) compared to HM- (24+/-11) or HT (20+/-9) controls. LDCC in HM- correlated with levels of CD8 cells bearing Leu7, whereas LDCC in HM+ correlated with levels of CD8 OKT10+ cells. Cell depletion experiments to more directly assess the role of CD8 subsets in LDCC confirmed that CD8 cells mediate LDCC in HM- and HM+ (80-90% inhibition). Depletion of Leu 7 removed greater than 50% of the lytic activity in HM- and an average of 35% in HM+. Depletion of OKT10+ CD8 cells had no effect on LDCC of HM-; preliminary experiments in HM+ have been variable. CONCLUSION: Our data indicate that, as has been shown previously in healthy control subjects, LDCC in HM- appears to be mediated predominantly by CD8 Leu7+ cells. However, despite the increased levels of CD8 Leu7+ cells, this CD8 cell subset does not appear to be the major contributor to the elevated LDCC in HM+.

Publication Types:

• Meeting Abstracts

Keywords:

• ADP-ribosyl Cyclase
• AIDS Vaccines
• Acquired Immunodeficiency Syndrome
• Antigens, CD
• Antigens, CD8
• CD8-Positive T-Lymphocytes
• HIV
• HIV Infections
• HIV Seropositivity
• Los Angeles
• Male
• T-Lymphocytes, Cytotoxic
• immunology

Other ID:

• 00298689

UI: 102178888

From Meeting Abstracts