Intrahost genetic variability of human herpes virus-8.

Studies were conducted to determine whether HHV-8 hyperactivity could be the consequence of the propensity of the host to multiple HHV-8 infection. The aim of the present work was to investigate HHV-8 intrahost genetic variability. HHV-8 subgenomic DNA was amplified by PCR from patients infected with HIV, health care workers (HCW) and bone marrow transplant recipients (BMT), and from oral lesional tissues of AIDS-Kaposi's sarcoma (KS) patients. As controls, blood from HIV-negative health care workers, and the cell lines BC-1, BC-2, and BCP-1 were used. Clones derived from amplicons originating from DNA fragments in open reading frame (ORF) 26 and ORF K1 were isolated. For each ORF, intra-specimen nucleotide sequence differences were determined. The extent of HHV-8 variation in clones derived from blood of patients infected with HIV was significantly higher than in blood from health care workers or post-bone marrow transplantation patients or in AIDS-KS tissue. Among the clones derived from the latter three categories of specimens, sequence variations were not significant. It is concluded that HIV-infected individuals can have multiple of HHV-8, but AIDS-KS lesions are associated with infection by a single HHV-8 variant or a small group of related variants.