Strategies in the development of human monoclonal antibodies.

A high-efficiency, HAT-sensitive heteromyeloma fusion line CB-F7 has been developed from an 8-Azaguanin-treated Ig-non-secreting human X mouse heterohybridoma. The use of this line allowed us to produce human hybridomas more successfully by fusion of cell material from blood, lymph node or spleen. A polyspecific repertoire of IgM isotype was detected among the hybridomas obtained from the spleen.