Fig. 6

Representative microphotographs of a 5 month-old fetal lung (a–c) and a 6 month-old fetal esophagus (d–f) immunostained for CR1 (a,d), CR3 (b,e) and in the absence of primary antibody as a negative control (c,f). Red arrows in (e) point out a patch of ciliated epithelial cells. Scale bar = 200 μm.