Immunoreagents reactive with a conserved epitope of human immunodeficiency virus type I (HIV-1) gp120 and methods of use

A method for determining the efficacy of a monoclonal antibody to neutralize primary isolates of Human Immunodeficiency Virus Type 1, said method comprising the steps of:

• providing a known concentration of H9 cells in a first receptacle, a second receptacle, a third receptacle, a fourth receptacle, and a fifth receptacle, wherein all five receptacles comprise the same concentration of H9 cells for inoculation;
• providing a primary HIV-1 isolate;
• adding fifty percent tissue culture infective doses of the primary HIV-1 isolate to four increasing concentrations of the monoclonal antibody, whereby resulting in four different mixtures of primary HIV-1 isolate and monoclonal antibody, wherein each mixture is contained in a separate container, and wherein the monoclonal antibody is selected from the group consisting of monoclonal antibodies produced by the cell line deposited with the ATCC under Accession No. CRL10758 and monoclonal antibodies produced by the cell line deposited with the ATCC under Accession No. CRL10464;
• inoculating the H9 cells of four of the five receptacles with the four different mixtures of primary HIV-1 isolate and monoclonal antibody, wherein each receptacle receives a mixture from only one container, whereby resulting in four different cultures;
• providing one control culture by adding a fifty percent tissue culture infective dose of the primary HIV-1 isolate to the fifth receptacle containing only H9 cells;
• preparing a supernatant from each of the four cultures and the one control culture, whereby resulting in five supernatants;
• determining the concentration of p24 antigen in each of the five supernatants, wherein the p24 antigen concentration is used as an indicator of virus infection;
• and
• determining the efficacy of the antibody to neutralize HIV infection by comparing the concentration of p24 antigen in each of the five supernatants.