Detection of reverse transcriptase by a highly sensitive assay in sera from persons infected with human immunodeficiency virus type 1

In an ultrasensitive assay for reverse transcriptase (RT), an in vitro-transcribed heteropoly-meric RNA sequence was used as a template and polymerase chain reaction (PCR) amplification with Southern blot hybridization served as a detection system for the cDNA reaction product. The assay, called Amp-RT, detected 9 tested retroviruses in unconcentrated culture supernatants diluted 10²- to 10⁵-fold. A comparative analysis using human immunodeficiency virus type 1 (HIV-l) revealed that Amp-RT was 100, 000 times more sensitive than the standard RT assay, 10, 000 times more sensitive than p24 antigen capture and branched DNA assays, and 100 times more sensitive than RT-PCR or TCID₅₀assays. Analysis of serum specimens from 42 HIV-l-infected persons by Amp-RT showed that 36 samples (85.7%) were RT-positive. In contrast, 41 serum specimens from persons seronegative for HIV-1 and human T lymphotropic virus types I and II were all Amp-RT-negative.