Effect of Cortisone on Natural Immunity to Schistosoma mansoni in Mice

Abstract

In 3 separate experiments small groups of mice of 2 strains were exposed to infection with S. mansoni and half of them were treated subcutaneously with 0.5 mg of cortisone beginning shortly prior to infection and ending on the 29th day (12 injections), 15th day (9 injections) and 7th day (7 injections) after infection, respectively. The various regimens of cortisone treatment employed did not increase susceptibility to the trematode parasite, as judged by numbers of adult worms recovered from hepatic portal tracts of the mice 7-8 weeks after infection. The treatments may have enhanced the natural immunity slightly, since significantly fewer worms were recovered from the cortisone-treated mice.