A SEMIQUANTITATIVE ASSAY FOR CD8(-CELL-MEDIATED SUPPRESSION OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 INFECTION() T)

A reproducible, semiquantitative assay was developed to measure the le vel of the anti-human immunodeficiency virus type 1 (anti-HIV-1) suppr essive activity of CD8(+) T cells. The assay had a wide dynamic range and could be applied to a relatively small number of fresh and cryopre served peripheral blood mononuclear cells and purified CD8(+) T cells. The suppressive activity was not due to cytolytic activity and was no t major histocompatibility complex class I restricted. Suppression of HIV-1 infection by CD8(+) T cells was consistently demonstrable with b oth endogenously infected autologous CD4(+) T cells and exogenously in fected allogeneic CD4(+) T cells. This assay can be used to monitor th e level of antiviral activity of CD8(+) T cells in a retrospective and prospective manner in studies of the natural history of HIV-1 infecti on and of subjects receiving anti-HIV-1 therapy and vaccines.