Quantitation of Cell-Free and Cell-Associated Kaposi's Sarcoma-Associated Herpesvirus DNA by Real-Time PCR

A real-time PCR assay for quantitation of Kaposi's sarcoma-associated herpes virus (KSHV or human herpesvirus 8) DNA was evaluated. The linear dynamic range was 10 to 10(5) copies of KSHV DNA (r(2) > 0.99). The accuracy of DNA purification and quantitation was less than ±0.4 log(10) copies for samples that contained from 10 to 10(5) copies of KSHV DNA. Cell-associated KSHV DNA was quantitated over a range of infected cell frequencies from 0.1 to 10(−5), and cell-free KSHV DNA in plasma was quantitated over a range of 100 to 10(6) copies/ml. Real-time PCR provides a convenient method for quantitation of cell-free and cell-associated KSHV DNA in laboratory and clinical specimens.