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 herpe s 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 DN A purification and quantitation was less than +/-0.4 log(10) copies for sam ples that contained from 10 to 105 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 10 0 to 10(6) copies/ml. Real-time PCR provides a convenient method for quanti tation of cell-free and cell-associated KSHV DNA in laboratory and clinical specimens.