PRAZIQUANTEL-INDUCED EXPOSURE OF SCHISTOSOMA-MANSONI ALKALINE-PHOSPHATASE - DRUG-ANTIBODY SYNERGY WHICH ACTS PREFERENTIALLY AGAINST FEMALE WORMS

The efficacy of praziquantel-treatment of murine Schistosoma mansoni-infections can be enhanced by concurrent administration of rabbit anti-sera with specificity for parasite antigens. Monospecific rabbit serum raised against S. mansoni worm alkaline phosphatase, that was reactive with the enzyme an the drug-treated female surface, was found to significantly and preferentially increase the mortality of female worms by PZQ. Immunoglobulins purified from the anti-alkaline phosphatase antiserum inhibited 54% of schistosome alkaline phosphatase enzymatic activity on the surface of praziquantel-treated worms. We propose that synergistic antibody-mediated death of drug-damaged worms is a consequence of the inhibition of drug-exposed alkaline phosphatase on the female worm surface by passively transferred antibody.