Administration of an anti-CD8 monoclonal antibody interferes with the clearance of chimeric simian/human immunodeficiency virus during primary infections of rhesus macaques.

Parenteral administration of a mouse anti-human CD8 monoclonal antibody (MAb) to rhesus macaques resulted in a transient depletion of CD8+ cells in both the peripheral blood and lymphoid tissues. When administered during primary chimeric simian/human immunodeficiency virus infections, the CD8 MAb caused marked elevations of plasma and cell-associated virus levels in both the peripheral blood and lymphoid tissues and led to prolonged depletion of CD4 cells. Taken together, these results directly demonstrate that CD8+ T lymphocytes are actively involved in controlling the acute phase of primate lentivirus infections.