[Specific killing of human leukemic T-cells by a monoclonal antibody coupled to the cytotoxin from Chinese cobra].
The immunotoxin (IT) was prepared by conjugating cytotoxin from Chinese Cobra (Naja naja Atra) venom with monoclonal antibody (McAb) Wu71 directed to human T-cells. First, calcium ions were used to suppress the cytolytic reaction while cell antigen was allowed to react with McAb. Then magnesium ions and the chelating agent EGTA were used to abolish the calcium inhibition. With this treatment, the IT showed high cytotoxicity for the leukemic cell line CEM, which was antigen positive (82.4% of the cells were killed at a concentration of 0.5 x 10(-6) mol/L of IT), but very little cytotoxicity for the antigen negative cell line Raji (23.3% cells were killed at the same concentration). Under scanning electron microscopy, it could be seen that the cell membranes of CEM were broken by IT, and the cells had died. The results suggest that the McAb Wu71 plus cytotoxin IT has potential application in leukemia therapy.
Chu
J
J
Institute of Medical Biology, Kunming.
D000911:Antibodies, Monoclonal; D003039:Cobra Neurotoxin Proteins / Q000494:pharmacology*; D006801:Humans; D000922:Immunotoxins / Q000494:pharmacology*; D015458:Leukemia, T-Cell / Q000473:pathology*; D013601:T-Lymphocytes / Q000276:immunology; D014407:Tumor Cells, Cultured / Q000187:drug effects
D000911:Antibodies, Monoclonal; D003039:Cobra Neurotoxin Proteins; D000922:Immunotoxins