RESUMO
This work was designed to study the dynamics of circulating schistosome antigens [CSA] both in serum and hepatic tissues to evaluate their role in the pathological changes in murine schistosomiasis mansoni in two strains of mice with different genetic make up [C57BL/6 and BALB/c] during the course of schistosomal infection. The detection of serum CSA was performed using sandwich ELISA. Immunolocalization of schistosomal antigens in hepatic tissue was studied using indirect immunofluorescent staining. In both techniques, an IgM anti-Schistosoma mansoni soluble egg antigen [SEA] monoclonal antibody [MAb] used. Immunolocalization as well as detection of CSA were studied weekly starting from the first week up to twelve weeks post-infection [p.i.]. The serum circulating antigen was detected as early as the first week p.i.; whereas, its detection in hepatic tissue was observed at a later stage [fourth week p.i.]. Serum circulating antigen levels reached their peaks at the 5th and 6th weeks p.i. in BALB/c and C57BL/6 mice, respectively, and then declined. The deposited schistosomal antigen in hepatic tissues reached their peaks at 7th- 8th week p.i. in both strains, but declined more rapidly in C57BL/6 mice than in BALB/c mice. The data denoted that the dynamics of circulating antigen both in the serum and the hepatic tissues varies according to the genetic background of the mice