The course of Angiostrongylus cantonensis infection in athymic nude and neonatally thymectomized mice.

BALB/c athymic nude and thymus-reconstituted nude mice and neonatally thymectomized BALB/c mice were infected with stage 3 larvae of Angiostrongylus cantonensis and the worm burdens of the mice were determined at various times after infection. When the nude and thymectomized mice were exposed to the parasite, some worms were found to migrate from the brain to lungs but died there without reaching maturity. This pulmonary arterial migration of the worms in the nude did not occur following thymic reconstitution. These data suggest that the inability of murine intracranial worms to migrate to the lungs is at least in part due to thymus-dependent mechanisms, and also that the failure of worm maturation in mouse lungs might be due to thymus-independent immune mechanisms and/or nonimmunological mechanisms.