Abstract: AIM:To compare the size of hepatic granulomas produced by eggs from various geographic strains of Schistosoma japonicum in Asia.METHODS:The size of each single-egg granuloma of productive stage was measured in the liver sections of C57BL mice infected with each of the following strains of S.japonicum,i.e.,Chinese Yunnan(Y) ,Chinese Guangxi (G) ,Chinese Sichuan (S) ,Chinese Anhui- Hubei (A ) ,Chinese Taiwan (T) , Japanese(J) and the Philippines(P) .The volume of each granuloma was calculated by the formula V =∏AB²/6, in which A and B stand for the two perpendicular axes. RESULTS: In the permissive host C57BL inbred mouse, though the average size of egg granulomas differed with the geographic strains used, themean volume of productive stage of egg granulomas for Chinese Taiwan strains, a zoophilic strain, was smaller than that detected in the other six anthrophophilic strains (Fig. 1). These differences were statistically significant (P < 0. 01). CONCLUSION: Some unique specificities migh t be occurred between the host-parasite relationship in the host infected with Chinese Taiwan strain of S. japonicum and that the immunobiology involved in the hosts would particularly be worth pursuing.

Key words: Schistosoma japonicum, strain, egg granuloma