Quantitation of human herpes virus 8 DNA in paraffin-embedded biopsies of HIV-associated and classical Kaposi's sarcoma by PCR

Background: Kaposi's sarcoma occurs in patients seropositive and seronegative for the human immunodeficiency virus (HIV) and has been associated with human herpes virus 8 (HHV8). The purpose of this study was to determine and to compare the amount of HHV8 DNA in formalin-fixed tissue sections of Kaposi's sarcoma. Methods: From 27 biopsies of Kaposi's sarcoma patients, tissue sections were taken and deparaffinized. Four patients were HIV seronegative and 13 were HIV seropositive. After extraction of DNA copy numbers of HHV8 and beta -globin were determined in every sample by quantitative PCR ELISA using an internal quantitation standard. Results were expressed as HHV8 per beta -globin. Results: No significant differences were found between biopsies from HIV-positive and HIV-negative patients (14.8+/-19.6 HHV8 per 1000 beta -globin in HIV-positive versus 18.0+/-23.5 in HIV-negative patients). Conclusions: These data suggest that HHV8 viral load in Kaposi's sarcoma is relatively low and does not differ in HIV-positive and HIV-negative samples. The importance of viral load determination for prognosis or treatment monitoring remains to be elucidated.