Schistosoma Granuloma

Eggs of Schistosoma mansoni and S. japonicum introduce differently composed granuloma (e.g., in liver), although their adults live in the same blood vessel system (around the intestine of their hosts). In the center of the granulomas of both species one or several eggs are situated. In S. mansoni these eggs are surrounded mainly by eosinophilic granulocytes, while in the case of S. japonicum neutrophils enclose the centrally located eggs. Then follow (in both cases) collagen fibers from the inner to the outer side layers of macrophages of hepatic stellate cells and a final surrounding layer composed of a mixture of macrophages, neutrophils, and B- and T-cells (Fig. 1).

Schistosoma Granuloma, Fig. 1

Light micrograph of a section through an egg granuloma of S. mansoni in the liver of a patient. Note the blue stained collagen