Abstract: Methods and composition for HIV diagnosis and treatment using monoclonal antibodies reactive with one or more neutralizing regions of HIV proteins, using the peptides or homologs thereof from that region, and using related nucleic acid segments. Exemplary neutralizing regions include selected portions of the env and gag genes from various HIV isolates. Monoclonal antibody secreting cell lines include HIV-gp110-1, -2, -3, -4, -5 and -6 (A.T.C.C. Accession Nos. HB9175, HB9176, HB9177, HV9405, HB9406 and HB9404, respectively) and HIV-p25-2, -3, -6 and -7 (A.T.C.C. Accession Nos. HB9407, HB9408, HB9409 and HB9410, respectively).

Abstract: Monoclonal antibodies capable of binding antigenic determinants within regions of the core proteins of the Human Immunodeficiency Virus and immortalized cell lines producing those monoclonal antibodies are provided. The monoclonal antibodies find use in a variety of ways, including HIV antigen detection in biological samples. Using these methods, individuals may be identified who are infected with HIV but who have not yet developed anti-HIV antibodies. The methods also find use in monitoring in vitro growth of HIV, and the efficacy of therapeutic agents and vaccines.