HUMAN HERPESVIRUS-8 - DETECTION OF NOVEL HERPESVIRUS-LIKE DNA-SEQUENCES IN KAPOSIS-SARCOMA AND OTHER LESIONS

Kaposi's sarcoma (KS) is a malignancy suspected of having an infectiou s etiology. Unique viral DNA sequences were recognized in KS lesions, using a novel technique that identifies small differences between two complex genomes. The virus had homology with the herpesvirus family, e specially Epstein Barr virus (EBV), yet it was distinct from the known herpesviridae, and was appropriately named human herpesvirus 8 (HHV-8 ) or Kaposi's sarcoma-associated herpesvirus (KSHV). HHV-8 DNA sequenc es were present in AIDS-associated KS, classic KS, African endemic KS, Mediterranean KS, iatrogenic KS, and KS in homosexual men without HIV infection. HHV-8 DNA sequences were also present in peripheral blood mononuclear cells (PBMC) of KS+ patients; body-cavity-based lymphomas in HIV positive patients without KS; and in tissue from a number of ma lignant and non-malignant lesions in patients without HIV infection. T he role of HHV-8 in KS and other malignancies is not known. Viruses ar e notoriously trophic for lesional tissue. Therefore, in order to dete rmine the role of HHV-8 in KS pathogenesis, HHV-8 needs to be isolated and shown to induce immortalization in a suitable system. Regardless of its role in KS, another human herpesvirus has been discovered, and the extent of its pathogenicity needs to be uncovered.