Affiliations: [a] Technical Research Institute, Snow Brand Milk Products Co. Ltd., Kawagoe, Japan | [b] Institute of Food Science and Technology, Faculty of Agriculture, Kyushu University, Fukuoka, Japan | [c] Graduate School of Gene Resources Technology, Faculty of Agriculture, Kyushu University, Fukuoka, Japan
Note: [] Address reprint requests to Hiroshi Shinmoto, Technical Research Institute, Snow Brand Milk Products Co. Ltd., 1-1-2, Minamidai, Kawagoe 350, Japan.
Abstract: Two lines of mouse-human hybridomas were fused to produce human bifunctional antibodies. A hybridoma that secretes human IgM (κ) class antiricin monoclonal antibody was treated with actinomycin D to inhibit cell growth. Another cell line, secreting human IgM (λ) class antidiphtheria toxin monoclonal antibody, was 6-thioguanine resistant (HAT sensitive). Six hybridomas secreting IgM with both κ and λ light chains were obtained. Two of them secreted antibodies with antiricin specificity (κ and λ light chains) and antidiphtheria toxin specificity (κ and λ light chains). Antidiphtheria toxin antibodies secreted from other hybrid hybridomas did not contain κ light chain, but λ chain. A hybrid hybridoma clone 5–29 secreted complete hybrid IgM with lowered affinity to diphtheria toxin. These results suggested unbalanced recombination of immunoglobulin polypeptide chains in hybrid hybridomas.
Keywords: human bifunctional antibody, mouse-human hybridomas, hybrid hybridomas
