Antigen-Specific Identification and Cloning of Hybridomas with a Fluorescence-Activated Cell Sorter

Myeloma-spleen cell hybrids (hybridomas) producing antibody to mouse immunoglobulin allotypes have been labeled with fluorescent microspheres coupled with myeloma protein antigens. The ratio of specific to nonspecific microsphere binding by viable hybridoma cells was about 100:1. By using a modified fluorescence-activated cell sorter (FACS), selected hybridoma cells in a mixture have been sorted individually into media in microculture wells, where, with thymocyte feeder cells, they developed into clones producing a desired monoclonal antibody. Viable cells were selected by measurement of their light scattering and autofluorescence properties. Rare antibody-producing clones were obtained without laborious screening and repeated subculturing. This technique should expand the range of monoclonal antibodies readily obtained from hybridomas and greatly facilitate the process of obtaining desired hybridomas.