Modification of immune responsiveness in murine Schistosomiasis mansoni. I. Time course after cercarial exposure.

The immune responsiveness of mice infected with 90 cercariae of Schistosoma mansoni has been investigated. Post-infection kinetics of antibody responses, delayed hypersensitivity and mitogen responsiveness show that there are profound disturbances of these immunological parameters starting 2 weeks after the infection. Although the final outcome is immunodepression the S. mansoni infection can produce immunostimulation. We have observed differences in the kinetics of the depression of humoral antibody responses in two strains of mice. It seems that the worms and not the eggs are of major importance in determining the observed alterations of immune responsiveness.