Evaluation of anti-Schistosoma mansoni IgG antibodies in patients with chronic schistosomiasis mansoni before and after specific treatment.

The circumoval precipitin test (COPT), enzyme-linked immunosorbent assay (ELISA) and the immunoblotting anti-adult worm antigen (AWA) and soluble egg antigen (SEA) tests were applied to 17 chronically schistosome-infected patients for the detection of anti-Schistosoma mansoni antibodies before and on four occasions after oxamniquine administration over a period of six months. Compared to a control group, schistosomiasis patients showed high levels of IgG antibodies in AWA and SEA-ELISA. A decrease in IgG levels was observed six months after treatment, although negative reactions were not obtained. Significant decreases in IgG1, IgG3 and, mainly, IgG4, but not anti-SEA IgG2 levels were observed six months after treatment, again without negativity. Analysis of anti-AWA IgG antibodies by immunoblotting before treatment showed a 31 kDa strand in 14 patients (82%) which disappeared in three cases up to six months after treatment; furthermore, anti-SEA IgG antibodies showed the same band in nine patients (53%) before treatment, which disappeared in only four cases up to six months after treatment.

Localization by immunoelectron microscopy of Schistosoma mansoni antigens in the glomerulus of the hamster (Mesocricetus auratus) kidney.

Adult worm antigen (AWA) and soluble egg antigen (SEA) were localized ultrastructurally by immunoelectron microscopy using two monoclonal antibodies in the glomeruli of hamsters infected with Schistosoma mansoni cercariae or injected with S. mansoni eggs. AWA was detected in all cercaria-infected groups from the 30th day on and was present mainly in cytoplasm of mesangial cells, mesangial matrix, and glomerular basement membrane, either as isolated gold particles or in small electron-dense deposits of probable immune origin. AWA was encountered also on the inner side of the glomerular basal membrane, close to endothelial cells, and in the foot processes of the glomerular epithelial cells. SEA was detected at similar sites, apparently in lesser amounts, in uninfected hamsters inoculated with S. mansoni eggs into the jugular vein. Schistosomal antigens are apparently processed mainly bymesangial cells which are considered to be critical in the pathogenesis of S. mansoni associated glomerulopathy. Mesangioproliferative glomerulonephritis, immunoglobulin (IgG and IgM), and C3 deposits were observed in hamsters in which AWA and SEA were visualized. During early phases of the infection and in hamsters in which granulomatous pneumonitis was induced by S. mansoni eggs, glomeruli were unchanged or showed a slight mesangial proliferation. Our findings suggests that egg antigens also contribute to the pathogenesis of experimental glomerulopathy in the hamster.

Eosinophil levels in the acute phase of experimental Chagas' disease.

Eosinophil dynamics, in bone marrow, blood and peritoneal exudate, of resistant C57B1/6 (C57) and susceptible A/Snell (A/Sn) mice was comparatively studied during the acute phase of infection by Trypanosoma cruzi Y strain. A decline was observed in bone marrow eosinophil levels in A/Sn, but not in C57 mice, soon after infection, those of the former remaining significantly below those of the latter up to the 4th day of infection. Bone marrow eosinophil levels of C57 mice declined subsequently to levels comparable to those of A/Sn mice, the number of these cells in this compartment remaining 50% those of non infected controls, in both strains, up to the end of the experiment on the 14th day of infection. The fluctuations in eosinophil levels in blood and peritoneal space were similar in both mice strains studied. Concomitantly with depletion of eosinophils in the marrow, depletion in blood and a marked rise of these cells in the peritoneal space. initial site of infection, occurred in both strains. The difference in eosinophil bone marrow levels, between C57 and A/Sn mice, observed in the first four days of infection, suggests a higher eosinopoiesis capacity of the former in this period, which might contribute to their higher resistance to T. cruzi infection.