Using a mouse model of biliary and intestinal cryptosporidiosis via gallbladder injection of C. parvum oocysts [30], we detected a significant increase in iNOS protein level in biliary epithelial cells from mice infected with C. parvum for two weeks, compared with the sham-infection control animals (Figure 2C and 2D). The gene discussed is NOS2; the disease is cryptosporidiosis.