Post-fusion selection of antigen-specific hybridomas

Abstract

The ability to create monoclonal antibodies has allowed great strides to be made in research and clinical medicine, and continues to contribute to progression in many areas. However, the technology involved is labor-intensive and often inefficient. A typical cell hybridization procedure will generate thousands of hybridomas, with the great majority being irrelevant. Conventional technology requires maintenance and testing of the total population, in order to identify the very few hybrids that are secreting antibody of the desired specificity. Particularly for antigens of low immunogenicity, this is clearly inefficient. -- The purpose of this study is to explore methods for selecting antigen-specific hybridomas soon after the fusion procedure. This would eliminate the unnecessary maintenance of irrelevant hybrids, reducing much of the time, effort and materials that are currently consumed in this technology. -- For these fusions, transfectant cells expressing HLA-DP molecules were the immunogens. Monoclonal antibodies recognizing DP polymorphisms were desired as serologic reagents, for matching donor-recipient pairs in bone marrow transplantation. Fused cells were grown as bulk cultures and Ag-specific selection was attempted, using the antigen as a probe for hybridomas expressing specific immunoglobulin receptors. Two methods were tested: immunomagnetism (by use of antigen-coated immunometallic beads), and panning (by use of the immunizing transfectant cells). The yield of antigen-specific hybridomas was compared to that obtained in conventional fusions. -- The results indicate that panning, using the procedure outlined in this study, is not a useful method for selecting DP-specific hybridomas from a post-fusion bulk population. Immunomagnetism, on the other hand, produced satisfactory results, offering a potentially useful way to increase the efficiency of monoclonal antibody generation.