r-82150 and zidovudine-triphosphate

To study the functional properties of HIV-1 reverse transcriptase (RT) from intact viral particles without the requirement for tissue culture expansion, a method that couples HIV-1 reverse transcription utilizing its endogenous RT (ERT) with polymerase chain reaction amplification (PCR) was developed. Detection of endogenous reverse transcripts from HIV particles by ERT-PCR was compared to HIV RNA PCR detection using avian myeloblastosis virus (AMV) RT from plasma samples from 45 HIV-1 infected patients. The HIV ERT-PCR method was capable of detecting plasma viremia with the same efficiency (29/29 patients) as the AMV RT HIV RNA PCR in patients with CD4 cell counts of less than 500/mm3. The determination of HIV-RT drug sensitivities using four well-characterized HIV-1 lab strains was assessed. The ERT-PCR method detected reduced sensitivity to TIBO R82150 (10 microM) in a TIBO resistant strain but not in the TIBO sensitive HTLV-IIIB viral mixture or an HTLV-IIIB clone. In summary, the HIV ERT-PCR method provides a useful approach for the detection of HIV and the characterization of RT sensitivities among HIV-1 strains.

Topics: Antiviral Agents; Benzodiazepines; Dideoxynucleotides; DNA, Viral; Drug Resistance, Microbial; HIV Reverse Transcriptase; HIV-1; Humans; Imidazoles; Polymerase Chain Reaction; Reverse Transcriptase Inhibitors; RNA-Directed DNA Polymerase; Sensitivity and Specificity; Thymine Nucleotides; Zidovudine

Recently, several classes of compounds have been shown to be potent, selective, and specific inhibitors of human immunodeficiency virus type 1 replication in vitro. These include the tetrahydroimidazo[4,5,1-jk][1,4]-benzodiazepin-2(1H)-one and -thione (TIBO) and the 1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)thymine (HEPT) derivatives. Both the TIBO and HEPT derivatives specifically inhibit human immunodeficiency virus type 1 reverse transcriptase (RT). From a comparative study of the characteristics of RT inhibition by TIBO and HEPT, and from the competition between TIBO and HEPT for RT inhibition, we infer that both classes of compounds, although structurally unrelated, are targeted at the same site of the enzyme. Detailed functional and kinetic analyses indicate that this target site is functionally and possibly also spatially related to the substrate binding site.

Topics: Antiviral Agents; Benzodiazepines; Dideoxynucleotides; HIV-1; Imidazoles; Kinetics; Molecular Structure; Recombinant Proteins; Reverse Transcriptase Inhibitors; Structure-Activity Relationship; Templates, Genetic; Thymidine; Thymine Nucleotides; Uracil; Zidovudine