ORIGINAL ARTICLE AN IMMUNOHISTOCHEMICAL EVALUATION OF ENZYMES IN

Abstract Innate Paneth cells (IPCs) contain various enzymes such as matrix metalloproteinase-? (MMP7), lysozyme, secretory phospholipase A, (sPLAz), and aI-antitrypsin (aIAT), which are considered to participate in important roles against bacteria and mucosal injury, while it is unknown whether metaplastic Paneth cells (MPCs) in ulcerative colitis (UC) have similar functions to IPCs. An immunohistochemical comparison between IPCs and MPCs was made using antibodies against these enzymes. The study included 20 patients with total colitis type of active UC. For six segments from the cecum to the rectum, ratios of the number of MPCs with enzyme positive granules (enzyme'<MlCs) and ratios of the number of MPCs with positive granules occupying more than a half of the cytoplasm (enzvme'<Ml'Cs) to that of all MPCs were calculated The populations of MMP7+-MPCs, MMP71/Z-MPCs and lvsozvme'<-Mj'Cs were significantly smaller than those of IPCs in the ileum taken from 20 controls (p<o.on Both MPCs and IPCs abundantly contained sPLAz positive granules, but had few alAT granules. MPCs were characterized by scant MMP7 and abundant sPLAz; MMP7 is capable of causing tissue injury and sPLAz is associated with mucosal repair. Although a population of MPCs is usually small in the colorectal mucosa of UC, they are suggested to come into existence to playa role of mucosal repair