Partial purification of native HIV transmembrane protein gp41: generation of polyclonal and monoclonal antibodies.

We partially purified the human immunodeficiency virus (HIV) glycoprotein gp41 from infected H9 cells by immunoaffinity chromatography using a column containing the M25 monoclonal antibody (diMarzo-Veronese et al., 1985). A pH 11.5 buffer worked best for eluting the glycoprotein from this column. The eluted gp41 was used in a sensitive slot blot immunoassay to detect antibodies to HIV in human sera and to prepare rabbit polyclonal antibodies and the 41-1S mouse monoclonal antibody. These antibodies reacted with gp41 in immunoprecipitation and in Western blot assays, but did not neutralize HIV in a syncytium-forming microassay. A pH 2.5 buffer was found to be the most effective solution for eluting gp41 from a 41-1S monoclonal antibody column.