Biliary cyst formation. A. Panels show 6 representative liver histopathology sections of B cell deficient (μ−/−) and sufficient (μ+/+) NOD.c3c4 mice. A. Mildly dilated bile ducts were observed scatteredly in B cell deficient mice whereas livers in B cell sufficient mice demonstrated marked ductal dilatation. B. Liver cyst formation was partly suppressed in B cell deficient mice at 24 weeks of age (μ−/−, n=15; μ+/+, n=15). C. The average diameter of three maximal bile cysts in the examined section was significant lower in 24 week old B cell deprived mice. D,E. No difference was observed in 8 week-old mice. (H&E staining. Black scale bars indicate 100 μm in A. *: p < 0.05, **: p < 0.01, ***: p < 0.001 in Mann-Whitney Test)