Although a clinical translation specifically addressing the effect of anti-Tat Abs in treating AIDS-KS is not available now, observational and interventional studies by our and other groups (extensively reviewed in [67]), indicating that the presence of anti-Tat antibodies and anti-Tat immunity are effective in controlling HIV/AIDS progression, suggest a protective role of anti-Tat antibodies due to the neutralization of extracellular Tat activities. This evidence concerns the gene TAT and Kaposi's sarcoma.