STUDY OF MONOCLONAL ANTIBODY-RICIN IMMUNOTOXIN

A method is described for linking intact ricin to antibody in a manner producing hindrance to the galactose-binding sites on the B chain of the ricin . The immunoto-xin was synthesized by reacting iodoacetybted ricin with thidated antibody.The antibody cativity of monoantibody-ricin was measured by ELISA, the results showed that the function of antibody binding to the target cells was retained. The study on the cyto-toxicity of the immunotoxin showed that it inhibited the 3H Ieucine incorporation to the target cells by 52% at a concentration of 10-9 M, it is about tenfold as potent as antibody-RTA, and the immunotoxin was not toxic at a concentration of 10-9 M to cultured normal fetal lung cell.