Studies of Acquired Immune Deficiency Syndrome (AIDS) are planned to focus on (a) laboratory research on the pathogenesis of AIDS and on specific anti-HTLV-III immunity in an epidemiologic context to delineate factors relevant to establishment of HTLV-III/LAV infection and to protection against the progrssion of HTLV-III/LAV infection to major immune cell damage and clinical AIDS; (b) clinical trials to treat or prevent HTLV-III/LAV infection, and the reultant opportunistic infections and to repair the immunologic deficiency in AIDs patients by use of anti-viral agents and cellular reconstitution and other means. Immunologic studies will focus on disorders within the CD4 populations, especially those occuring in the earliest periods after HTLV-III/LAV viral infections. Antibodies to HTLV-III/LAV that prevent immune cell damage and T cell and NK cell factors that help prevent KS and OI will be defined. Immune cell changes in the absence oif HTLV-III/LAV infection which may permit KS developmemt will be sought. A series of phase II trials are proposed for patients with AIDs-KS using several anti-HTLV-III drugs to determine their anti-retroviral and immunorestorative effects and whether eradication of the virus induces KS tumor regression. Also, anti-viral agents will be used prior to marrow infusion in order to facilitate immune restoration.