Generation of somatic cell hybrids capable of proliferating and secreting human monoclonal antibody without any growth factor supplements

A novel cell line called Trioma, which can proliferate and secrete a human monoclonal antibody in the basal medium, was established. Trioma was generated by somatic cell hybridization with human × human hybridoma and A431c, which is a cell line able to grow autonomously in the basal medium. A Trioma called TriH8 has been kept growing in the DMEM/F-12 medium for over 1 year and stably producing stomach cancer–reactive human IgM into culture medium at 10 μg/ml. TriH8 has a characteristic cytological phenotype, that is, to diminish cell growth in the presence of epidermal growth factor.