DEVELOPMENT AND EVALUATION OF AN HIV-1 TRANSFECTION-NEUTRALIZATION ASSAY

We developed a transfection-neutralization assay for human immunodefic iency virus type 1 (HIV-1) infectious molecular clones. In this assay CD4 negative adherent cells, transfected in microtiter plates with fix ed amounts of proviral DNA of molecular HIV-1 clones, are cocultivated with CD4 positive T cell lines or primary peripheral blood mononuclea r cells (PBMC) in the presence of anti-HIV-l sera or monoclonal antibo dies (MAbs). Results obtained with this technique were reproducible an d compared favorably with a conventional cell-free infection inhibitio n assay. The transfection-neutralization assay obviates the need for v irus stock preparation and, therefore, is particularly suitable for th e evaluation of HIV-1 clones with slow replication kinetics and of rec ombinant chimeric HIV-1 clones inclined to undergo additional mutation s during stock preparation. The potential value of this assay for the analysis of the specificity of neutralizing sera and MAbs was demonstr ated in experiments with V3 chimeric molecular clones.