解説Sequential sections of a colon crypt showing normal high expression of PMS2 (A), ERCC1 (B) and ERCC4 (C).tiff
English: Sequential sections of the same colon crypt with immunohistochemical staining (brown) showing normal high expression of DNA repair proteins PMS2 (A), ERCC1 (B) and ERCC4 (XPF) (C). This crypt is from the biopsy of a 58 year old male patient who never had colonic neoplasia and the crypt has high expression of these DNA repair proteins in absorptive cell nuclei throughout most of the crypt. Note that PMS2 and ERCC4 (XPF) expression (in panels A and C) are each reduced or absent in the nuclei of cells at the top of the crypt and within the surface of the colonic lumen between crypts. Original image, also in a publication.[1]