Schistosoma mansoni in mice: modulation of granulomatous response after reinfection and chemotherapeutic treatment

ABSTRACT

Mice previously infected with Schistosoma mansoni, and cured by specific treatment (400 mg/kg oxamniquine,p.o.) in tire chronic phase of the disease, were infected 20 days after treated to assess their capacity for modulalion of the granulomatous response. Histopathologic examination of the animals'liver, at 60 days after reinfection, evidenced the presence of typical granulomas of the chronic phase in most animals. This infer that the capacity for modulalion of the granulomatous response had been maintained, thus preventing a new acute phase of lhe disease. Conversely, a group of previously infected mice, untreated and submitted to reinfection, showed reactivation of the granulomatous response in 50 per cent ofthe animals. The possible implications of these findings in human schistosomiasis mansoni are discussed.