x Antigen Spleen cells Immunization Cell fusion Monoclonal antibodies Adapted from Milstein (1980) Scientific American, Oct. p.58 1 2 3 4 Antigen m 1 2 3 4 Spleen cells Immunization + Myeloma B cell 1 2 3 Cell fusion 1 2 3 4 4 x 1 2 3 4 1 2 3 4 Monoclonal antibodies 說明文字 Antiseum Pure single Ab A mixture of all Ab If a single B cell was picked up and cultured, then it will produce only one kind of antibody. But B cell can not survive well in the culture. Each B cell produces only one kind of antibody, which binds to its specific antigen. Conventional antiserum is the mixture of all antibodies produced by B cells from spleen. After immunization, the mouse spleen contains B cells producing specific antibodies. Each hybridoma line can produce pure single antibody, called monoclonal antibody. If B cell is fused with myeloma, the fused cell might be cultured and produce antibody. Myeloma cell can be cultured in the test tube, but can not produce useful antibody.