Differential immunoregulation of granulomatous inflammation, portal hypertension, and hepatic fibrosis in murine schistosomiasis mansoni

The present study investigates the immunoregulation of hepatic fibrosis in experimental murine schistosomiasis. Disease parameters measured were portal pressure, hepatic granuloma area, hepatic interstitial collagen, and glycosaminoglycans. C57BL/6 mice were infected with 25 Schistosoma mansoni cercariae and administered splenocytes or serum derived from uninfected mice or chronically infect syngeneic mice at 6 and 7 wk of infection. Immunologically mediated modulation was noted in animals receiving splenocytes derived from chronically infected mice. Both a reduction in portal pressure and hepatic granuloma areas were noted. Hepatic collagen content but not glycosaminoglycan content was reduced by the administration of either lymphoid cells or serum from chronically infected mice. The isotypic profile of hepatic interstitial collagens was modulated by both the administration of serum or lymphoid cells. Augmented levels of type III collagen was noted on administration of serum derived from chronically infected mice, whereas type I collagen levels were relatively elevated on administration of splenocytes. The data indicate that immunomodulation of inflammation and hepatic fibrosis can occur in murine schistosomiasis but that fibrotic events and inflammatory processes are independently modulated.