Establishment and comparison on mice model of Clonorchis sinensis

Objective To observe pathological changes of liver tissue and detectable rate of eggs from different strains of mice infected with various doses of Clonorchis sinensis metacercaria.Methods BALB/c(Ⅰ),C57BL/6(Ⅱ) and Kunming(Ⅲ) mice were orally infected with 10,20 and 30 metacercariae of C.sinensis,respectively,and normal mice were served as controls.20-30 days post infection the eggs in feces were accounted after digestion by NaOH solution.A portion of mice were sacrificed 30 days after infection and the liver tissues were taken out for pathological examination.The remaining mice were bred till 12 weeks post infection.Results The detectable rates of eggs in BALB/c(Ⅰ),C57BL/6(Ⅱ),Kunming(Ⅲ)mice were 79.17%,12.5%,37.5%,respectively.There were statistically significant differences(P0.005) among the 3 strains of mice.Hepatomegaly was observed in infected BALB/c and Kunming mice.Moreover,cholangiectasis,thick bile duct wall and inflammatory cell infiltration were all observed in livers under light microscopic examination,whereas C57BL/6 mice had no obvious pathological change.Conclusion BALB/c mice are susceptible to C.sinensis infection,while Kunming mice are less susceptible.C57BL/6 are resistant to C.sinensis infection.The dose of thirty metacercariae is suitable for infecting mouse to dynamically examine host situation and immunity.