Further studies on genetic variation of hepatosplenic disease and modulation in murine schistosomiasis mansoni.

The influence of genetic factors on the modulation of hepatosplenomegaly, portal venous pressure and granuloma size in chronic murine schistosomiasis mansoni was studied. Experiments with congenic mice confirmed previous observations that after 8 weeks of infection these disease manifestations are influenced by non-H-2 genes. During chronic infection (20 weeks compared to 8 weeks of infection), hepatosplenomegaly was minimally altered. Portal venous pressure was found to increase in 129/J and BALB/cJ mice, did not change in C57BL/6J and DBA/2J and decreased in CBA/CaJ mice. Simultaneous measurements of granuloma size delineated two groups: decrease of greater than 40%--C57BL/6J, DBA/2J and CBA/CaJ strains and decrease of less than or equal to 20%--129/J, BALB/cJ and C3H/HeJ mice. There was no consistent correlation between the magnitude or direction of alterations in portal pressure and granuloma size among the various strains studied. Furthermore, these alterations were independent of changes in parasite burden (adult worms or hepatic eggs). This amelioration of disease (modulation) was found to be influenced by a small number of non-H-2 genes.