Absorptive cells and goblet cells in crypts express DNA repair proteins differently. These three panels show parts of single crypts from a biopsy of a male patient who had a 1.5 cm tubular adenoma, stained by IHC for Pms2 (A), Ercc1 (B) and Xpf (C). Goblet cells of the crypts have a large "balloon like" region containing mucin granules (cytoplasmic white areas under these staining conditions). The other cells in the crypts are absorptive cells. Arrows indicate some nuclei of goblet cells (on the outer edges of the crypts) that have reduced or absent expression for Pms2, Ercc1 and Xpf. Images taken at 1000×.