Detection of Reverse Transcriptase by a Highly Sensitive Assay in Sera from Persons Infected with Human Immunodeficiency Virus Type 1

Abstract
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 TCID50 assays. 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.