HUMAN-HERPES-VIRUS-8 (KAPOSIS-SARCOMA HERPESVIRUS)

Human herpes virus 8 (HHV-8) is a recently discovered herpesvirus rela ted to Herpesvirus saimiri and Epstein-Barr virus (EBV). It has been a ssigned to the Rhadinovirus genus (gamma-2 herpesvirus) on the basis o f its genomic sequence and structure. HHV-8 is the first member of thi s genus known to infect humans and it is now evident that it is the li kely cause of Kaposi's sarcoma (KS). The virus is present in endotheli al and spindle cells of KS, and in HIV disease the presence of HHV-8 i n peripheral blood, and/or serum IgG antibodies to HHV-8, predicts the development of AIDS-related KS. HHV-8 can also infect CD19 + B cells and is of aetiological significance in the development of body cavity B cell lymphomas of AIDS. Of note, the translation products of viral o pen reading frames (ORFs) reveal HHV-8 to be a molecular pirate, capab le of producing homologues of several human gene products that may res ult in alterations in cell cycle arrest, inhibit apoptosis and cell-me diated immune responses, and thus provide the potential for tumour pro duction. (C) 1998 Elsevier Science Ltd. All rights reserved.