Epithelial cells, but not immune cells, are the major cellular source of IL-25 in the small intestine. Mice were infected with N. brasiliensis and studied 9 days later. (A) LCM combined with qPCR technique was performed to determine mRNA expression in specific cell populations from captured intestinal epithelial (EC), lamina propria (LP), and smooth muscle (Muscle). (B) Frozen tissue blocks of mid-jejunum were prepared and the sections were cut for immunofluoresence staining with anti-IL-25mAb. Pictures are representative of each group of at least 5 mice. Original magnification, x600.