Detection and genetic polymorphism of human herpes virus type 8 in endemicor epidemic Kaposi's sarcoma from West and Central Africa, and South America

Kaposi's-sarcoma-associated herpesvirus(KSHV)/human-herpes-virus-8(HHV-8) s equences originally detected in AIDS-associated Kaposi's sarcoma have been found in almost every KS tested, whether endemic, classic, iatrogenic or ep idemic. Most of the studies on African KS involved East African patients. W e report herewith the study of 17 African or Guyanan KS patients, 3 with ep idemic KS (EKS) from Central African Republic, 3 from Senegal(2 EKS and I e ndemic KS), 3 EKS from Cameroon and 8 from French Guiana (3 EKS and 5 endem ic KS). Serum-specific antibodies directed against latent and/or lytic HHV- 8 antigens were present in 16 of them (94%), detected either by immunofluor escence assay and/or by immunoperoxidase. Polymerase chain reaction (PCR), using specific primers for HHV-8 ORF26 (233 bp) and ORF75 (601 bp), was car ried out on DNA extracted from KS cutaneous biopsies, clinically uninvolved skin biopsies and peripheral-blood mononuclear cells (PBMC). HHV-8 DNA was detected in 16 out of 16 (100%) KS biopsies, regardless of their origin or clinico-pathological sub-type, in 7 out of 15 (47%) normal skin samples an d 7 out of 16 (44%) PBMC. Comparative PCR, carried out in 7 patients, regul arly found a much higher viral load in KS biopsies than in autologous norma l skin and PBMC samples. Sequencing of fragments of the ORF26 and of the OR F75 demonstrated that the 16 HHV-B strains were of the A, B or C sub-type. Furthermore, sequences of the entire ORF KI of 4 strains showed that these HHV-8 strains of African origin were of the A5 or the B sub type. (C) 2000 Wiley-Liss, Inc.