Preferential loss of Leu 8-, CD45R, HLA-DR+ CD8 cell subsets during in vitro culture of mononuclear cells from human immunodeficiency virus type I (HIV)-seropositive former blood donors.

Recent data from our laboratory showed that the CD4:CD8 cell ratio increased significantly during in vitro culture of unstimulated mononuclear cells (MC) from HIV-infected persons. To test the hypothesis that this increase reflected a decline in CD8 cell levels, changes in CD4 and CD8 cell levels during culture of MC were assessed quantitatively. These analyses were accomplished using a Spectrum III flow cytometer, which analyzes a constant volume (0.02 ml) of cell suspension. The number of cells counted within this volume (termed the sip count) thus reflects the cell number in the suspension. To establish day 0 sip counts, aliquots consisting of 200,000 lymphocytes were treated with monoclonal antibodies, resuspended in 1 ml of buffer, and analyzed. Also on day 0, identical cell aliquots were placed in microtiter wells and cultured for 3 days. Cells retrieved from individual wells were then analyzed as on day 0. The mean relative recoveries (RR) of lymphocytes, CD4 cells, and CD8 cells were significantly lower in the HIV group (N = 28) than in the control group (N = 26). For the HIV group, CD8 cell RR was significantly lower than CD4 cell RR. Dual-color analyses showed that CD4 cell loss in the HIV group did not occur preferentially within CD4 subsets defined by Leu 8 or CD45R expression. Similarly, CD8 cell loss did not occur preferentially within CD8 subsets defined by Leu 7 expression. In contrast, CD8 cell loss did preferentially affect Leu 8-, CD45R-, and HLA-DR+ CD8 subsets, compared to the reciprocal CD8 subsets.(ABSTRACT TRUNCATED AT 250 WORDS)