FIG 3

Expression of CEACAM5 in human lung tissues. Immunostaining of CEACAM5 and DPP4 was performed on paraffin slides of normal human lung tissues. Representative images of CEACAM5 and DPP4 expression in various regions of the human lung are shown, including the bronchi (A), small airways (B), and alveoli (C). The arrowheads indicate alveolar macrophages with CEACAM5 and DPP4 coexpression. Bars, 50 μm.