J. Immunofluorescent staining of Prom1, CK19 and HNF4α in two serial cryosections of mouse liver. The boxed area in the top panel was magnified and presented as the bottom panel. Asterisks (*) in the top panel indicate cholangiocytes of the bile bucts and triangles (Γ) in the bottom panel indicate hepatocytes. Scale bar, 100 μm. 