Identifying phenotypes involved in susceptibility to Schistosoma mansoni infection in F1B6CBA mice.

Schistosomiasis is a disease with a strong genetic component influenced by socioeconomic and ecological factors. Epidemiological studies have identified several genetic regions involved in the schistosomiasis susceptibility. However, it is not well known what physiological traits are predisposing to the disease. The study of experimental infections in inbred mouse strains with variable genetic susceptibility to the disease offers a good opportunity to tackle this question. F1B6CBA hybrid between the most divergent strains was infected in order to characterize the immunophenotypes that correlate with the susceptibility of schistosomiasis disease in mice. Complete blood counts and immunophenotype were determined at 0, 3, 6, and 9 weeks post infection. Nine weeks after cercariae exposure, animals were perfused and worm recovery was assessed. A large number of hepatic lesions, a reduction in the eosinophil and basophil count in the acute phase of infection and the decreased number of monocytes, neutrophils and B-lymphocytes are phenotypes associated with increased susceptibility to S. mansoni infection.