Studies on the host-parasite relationship of Schistosoma japonicum in normal and immunosuppressed mice.

Infections of Schistosoma japonicum were studied in mice which were immunosuppressed either by thymectomy and administration of antithymocyte serum or by treatment with hydrocortisone acetate. The relation of S. japonicum with the immunosuppressed host differed with that reported for Schistosoma mansoni. The pathogenesis of the S. japonicum infection in the immunosuppressed host was less severe than that caused by S. mansoni, with respect to survival of, and hepatocellular damage to, the host. In contrast with S. mansoni, S. japonicum did not have a reduced fecundity in immunosuppressed mice and there was no significant reduction in the numbers of faecal eggs excreted by these hosts.