A BROADLY NEUTRALIZING HUMAN MONOCLONAL-ANTIBODY AGAINST GP41 OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1

We have established a hybridoma clone, designated 2F5, secreting a neu tralizing human monoclonal antibody (MAb) specific for gp41 of human i mmunodeficiency virus type 1 (HIV-1). The epitope of MAb 2F5 was mappe d to amino acid sequence Glu-Leu-Asp-Lys-Trp-Ala on the ectodomain of gp41. In this study different in vitro test systems were used to chara cterize the neutralizing properties of MAb 2F5. In syncytium inhibitio n assays, fusion inhibition experiments, and neutralization assays on different HIV-susceptible cells (H9, U937, and peripheral blood mononu clear cells) MAb 2F5 showed broad-spectrum neutralizing capacity again st HIV-1 laboratory isolates IIIB, MN, RF, and SF2. In addition, prima ry isolates from AIDS patients were also neutralized.