DETECTION AND QUANTIFICATION OF HUMAN-IMMUNODEFICIENCY-VIRUS RNA IN PATIENT SERUM BY USE OF THE POLYMERASE CHAIN-REACTION

Human immunodeficiency virus (HIV) RNA was detected and quantified in the serum of HIV-seropositive individuals using the polymerase chain reaction (PCR) and a nonisotopic enzymelinked affinity assay. Of 55 HIV-infected patients who were not receiving therapy, serum HIV RNA was detected in 9 of 19 who were asymptomatic, 11 of 16 with AIDS-related complex (ARC), and 18 of 20 with AIDS, with copy numbers ranging from 10(2) to greater-than-or-equal-to 5 x 10(4)/200-mu-l of serum based on a relationship between absorbance and known copy number of gag gene RNA. Linear regression analysis demonstrated a correlation between infectious titer in 42 patient sera cocultured with donor peripheral blood mononuclear cells (PBMC) and PCR product absorbance (r = .70, P < .01). Serum HIV RNA detected by PCR also correlated with serum p24 antigen positivity, CD4 counts < 400/mm3, and the presence of HIV-related symptoms or disease. Quantification of infectious HIV RNA in cell-free serum by PCR may be useful as a marker for disease progression or in monitoring antiviral therapy.