DELETION OF T-LYMPHOCYTES IN HUMAN CD4 TRANSGENIC MICE INDUCED BY HIV-GP120 AND GP120-SPECIFIC ANTIBODIES FROM AIDS PATIENTS

CD4, a T cell receptor for major histocompatibility complex class II a ntigen, is a key regulator of immunological reactivities. When engaged together with the T cell antigen receptor, CD4 enhances immune reacti ons, whereas when ligated independently of the antigen receptor CD4 in hibits the activation of T cells or initiates their deletion. CD4 serv es also as a receptor for the human immunodeficiency virus (HIV), whic h binds the receptor with high avidity through its envelope molecule, gp120. Studies in tissue culture have shown that its affinity to CD4 g ives the virus opportunities to utilize CD4-mediated signaling and to manipulate immunocytes. We show here in human CD4 transgenic mice that appropriately cross-linked HIV envelope protein causes massive deleti on of MV-reactive T cells in vivo.