Short report: limited and short-lasting humoral response in Taenia solium: seropositive households compared with patients with neurocysticercosis.

Epidemiologic data suggest that 30-40% of Taenia solium-seropositive people become spontaneously negative without acquiring cysticercosis. To compare the responses of these individuals with those of patients with neurocysticercosis, we screened seropositive persons among family members of 16 patients. We searched for specific antibodies in patients and their 118 households by an enzyme-linked immunoelectrotransfer blot assay using specific glycoproteins of T. solium metacestodes. We found six seropositive individuals without neurocysticercosis among members of four families. The matching patients were young, harbored viable cysts, and had short evolution of disease. The baseline response of healthy seropositive individuals was scarce and showed a low frequency of antibodies against glycoproteins GP39-42 and GP24, which are immunodominant in patients with neurocysticercosis. Moreover, they became spontaneously negative in few months. The response of patients was heterogeneous as shown in other studies. The results of this work support a highly dynamic host-parasite immunologic interaction and suggest individual susceptibility or level of exposure among family members.