Angiostrongylus cantonensis: role of eosinophils in the neurotoxic syndrome (Gordon-like phenomenon)

The role of eosinophils in the pathophysiology of Angiostrongylus cantonensis infections was investigated in nonpermissive (guinea pig) and permissive (rat) hosts. Neurological symptoms similar to the Gordon phenomenon (ataxia, tremor, paralysis) together with a loss of Purkinje cells in the cerebellum were observed after intracraneal injection of human eosinophil extracts or after infection with A. cantonensis, only in guinea pigs and not in rats. Blood eosinophilia as well as eosinophil numbers present in the cerebellum and in the cerebrospinal fluid were higher in guinea pigs than in rats, at all times after infection with A. cantonensis. Increased levels of cytotoxicity toward L3 larvae in vitro were obtained in the presence of guinea pig eosinophils and IgE antibodies, rather than with the corresponding rat effector system. The detection of one eosinophil granule component, the eosinophil peroxidase, in the cerebrospinal fluid from infected guinea pigs but not from rats suggested that in nonpermissive hosts, neurological disorders, similar to the previously described Gordon phenomenon, might be due to eosinophil neurotoxins released after interaction of eosinophils with the parasites.