HUMAN MONOCLONAL ANTIBODIES TO HIV

The development of human IgG monoclonal antibodies (MoAbs) to HIV
has been very difficult and there are few reports on this in the
literature. We have developed the methodology and verified our
ability to regularly make human IgG anti-HIV MoAb-producing
hybridomas from the lymph nodes and spleens of HIV-infected
subjects. Eight stable hybridomas producing 2-5ug/ml
(106cells)/d have been developed. These react with GP160/120,
GP160/41, P55/24 and presumed conformational epitopes. One of
these neutralizes HTLV-IIIB and another enhances infectivity. We
hypothesize that human anti-HIV MoAbs which can neutralize HIV,
mediate ADCC or C'lysis or can be cytotoxic to HIV-infected cells
when coupled to toxins may be useful in AIDS prophylaxis or
therapy. Furthermore, if anti-idiotype antibodies to our
enhancing antibody could be developed using our hybridoma
methodology, these might also potentially be useful clinically.
In addition, we have also found that lymph node and spleen
lymphocytes can be stored in liquid nitrogen and thawed up to one
year later to yield cells which can readily be fused and made
into hybridomas producing anti-HIV MoAbs. They, and other human
anti-HIV MoAbs, may be useful in characterizing the antigens and
epitopes recognized during the patient's immune response
including those related to antibody mediated enhancement of
infection. Lymph nodes and spleens, obtained at clinically
relevant surgery will be processed as single cell suspensions,
fused with our unique fusion partner (P3U1), screened by ELISA
against HIV-infected and non-infected cells and cell lysates as
well as defined relevant synthetic GP120 or GP41 epitopes and
then cloned and expanded to produce specific MoAbs. These will
be characterized for cellular and antigenic reactivity by
immunofluorescence, flow cytometry, Western blotting and
neutralization/enhancement assays. With our collaborators, we
will prepare synthetic peptides which represent the already
identified relevant eptitopes or GP120a and GP41 and identify the
reactive epitope of each human MoAb. Based on our record of
accomplishment, 10-20 MoAbs can be developed and characterized
per year. Various clinically relevant experiments such as ADCC,
neutralization by mixtures of MoAbs or MoAbs + patient sera,
cytotoxicity of toxin-MoAb conjugates will be done to select
promising MoAbs for clinical trials as well as potential
diagnostic uses. Finally, we have initiated and will further
exploit this unique resource and carry on the above described
work.