Human monoclonal antibody directed against gag gene products of the human immunodeficiency virus.

Tonsillar B lymphocytes from an asymptomatic individual infected with HIV were transformed with EBV. A cloned lymphoblastoid cell line was obtained that secreted human mAb (IgG4 subtype) against the known gag gene products of 55,000 and 25,000 Da and a protein of 40,000 Da. The latter p40 protein appears to be a HIV gag-related gene product that is also recognized immunologically by individuals infected by HIV. Although the mAb detects infection of cells by different HIV isolates, it does not neutralize HIV or show activity in an antibody-dependent cytotoxicity assay.