(Public Library of Science, 2012) Sholukh, Anton M.; Mukhtar, Muhammad Mahmood; Humbert, Michael; Essono, Sosthène S.; Watkins, Jennifer D.; Vyas, Hemant Kumar; Shanmuganathan, Vivekanandan; Hemashettar, Girish; Kahn, Maria; Hu, Shiu-Lok; Montefiori, David C.; Polonis, Victoria R.; Schur, Peter; Ruprecht, Ruth Margrit
Existing technologies allow isolating antigen-specific monoclonal antibodies (mAbs) from B cells. We devised a direct approach to isolate mAbs with predetermined conformational epitope specificity, using epitope mimetics (mimotopes) that reflect the three-dimensional structure of given antigen subdomains. We performed differential biopanning using bacteriophages encoding random peptide libraries and polyclonal antibodies (Abs) that had been affinity-purified with either native or denatured antigen. This strategy yielded conformational mimotopes. We then generated mimotope-fluorescent protein fusions, which were used as baits to isolate single memory B cells from rhesus monkeys (RMs). To amplify RM immunoglobulin variable regions, we developed RM-specific PCR primers and generated chimeric simian-human mAbs with predicted epitope specificity. We established proof-of-concept of our strategy by isolating mAbs targeting the conformational V3 loop crown of HIV Env; the new mAbs cross-neutralized viruses of different clades. The novel technology allows isolating mAbs from RMs or other hosts given experimental immunogens or infectious agents.
