Research Progress on Human Defensin 5 / 中国普外基础与临床杂志

Objective To review the characteristics of human defensin 5 (HD 5), including molecular structure, antibacterial activity and gene expression, and to show its development prospect as a new drug in the treatment of enterogenic infection. Methods The published papers about HD 5 were reviewed to summarize its research progress. Results Being a 3-5 KDa cationic peptide rich in cysteine and arginine, especially without glycosylated side chain, HD 5 plays its antibacterial role against positive and negative Gram's bacterium, fungi, spirochete, protozoan and enveloped virus with the special active center composed of three disulfide bonds. HD 5 encoding gene alpha defensin 5 (DEFA 5) localizes at the 8th chromosome P21 pter with 449 bp, which includes five pieces of sequence: 5′ untranslated region (1-40),signal peptide (41-97), propiece (98-226), mature peptide (227-322),and Poly A (433-438).Conclusion As a broad spectrum and effective endogenous antimicrobial peptide, HD 5 would be a promising alternative peptide against enterogenic infection if the accessibility to its mass production is settled.

Inhibition of clotrimazole on Paneth cell defensins / 中国药理学通报

Aim To investigate the Clotrimazoles (CLT) inhibitive effect on the secretion of ?-defensins of the Paneth cells.Methods The ?-defensin mRNA expression is determined by semi-quantitative RT-PCR. The secretion of defensins is determined by dot-blot and ELISA. Results CLT has no influence on the defensin mRNA expression. All of 125 nmol?L -1, 250 nmol?L -1 and 500 nmol?L -1 CLT can inhibit the secretion of ?-defensins. Conclusion CLT could inhibit the secretion of defensins, which suggests that CLT maybe influence the function of small intestine

Paneth Cell-rich Carcinoma of the Stomach: A case report

Paneth cell-rich carcinoma is essentially an adenocarcinoma with a predominance of Paneth cells. A 60-year-old male patient was admitted with a history of abdominal distension for several months. Endoscopic examination revealed a large ulceroinfiltrative tumor involving most of the areas of the stomach. The biopsy of the lesion confirmed poorly differentiated adenocarcinoma and total gastrectomy was followed. The submitted total stomach contained a diffuse infiltrative Borrmann type IV mass with ulceration, 8.0 3.5 cm, at the body along the lesser curvature. Microscopically, it was composed of Paneth cell differentiated cancer cells and poorly differentiated tubular adenocarcinoma cells. The Paneth cell differentiation was characterized by cytoplasmic coarse eosinophilic granules, which were PAS-positive and positive reaction for lysozyme. Electron microscopic examination showed numerous, spherical, electron-dense, homogeneous granules corresponding to those in Paneth cells as well as mucin granules in the signet-ring cells, and various intermediate forms in some cancer cells, which might be immature in the Paneth cell lineage.

Trace amounts of enhancing factor/phospholipase A2 in mouse peritoneal exudate cells.

Enhancing factor (EF), a mouse phospholipase A2 (PLA2), has been purified from the small intestines, based on its ability to increase the binding of epidermal growth factor in a radioreceptor assay. EF/PLA2 was found to be localized predominantly in the Paneth cells in the small intestines. Whether mouse intestinal EF/PLA2 is identical/similar to mouse secretory PLA2 was to be determined. Phospholipases are known to play a crucial role in the process of inflammation. This paper reports the presence of trace amounts of EF/PLA2 in the peritoneal exudate cells. Western blot analysis of the acid extracts showed the presence of a 14 kDa immunologically cross-reactive protein. RT-PCR analysis using EF specific primers amplified a ~ 700 bp product which was further confirmed to be EF-specific by nested PCR analysis and sequencing. Presence of EF in the peritoneal exudate cells could be a unique mode of transport of growth factor modulator to the site of injury to aid in regeneration/cell proliferation of damaged tissue.

Neoplastic Paneth cells in the experimental murine carcinoma of the small intestine

The purpose of this study is to elucidate the participation of Paneth cells in experimentally induced adenocarcinoma of the intestine. The rats were fed with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) dissolved in drinking water ad libitum at a concentration of 100 micrograms/ml for 28 weeks. They were sacrificed 12 weeks after the last MNNG administration. A number of tumor cells containing large eosinophilic granules in their supranuclear cytoplasm (Paneth cells) were observed in about 20% of the experimentally induced adenocarcinoma of the small intestine. The granules were stained positively with Lendrum, periodic acid-Schiff, Masson's trichrome, and Mallory's phosphotungstic acid hematoxylin. Ultrastructurally, the granules were round, osmiophilic, and relatively even in size. We compared the morphologic features of the Paneth cell-containing small intestinal adenocarcinomas (Group I) with those without Paneth cells (Group II). Group I was distinguished from Group II by its better differentiation, larger tumor size and lower incidence of calcification. Although Paneth cells are extremely rare in human gastrointestinal carcinomas, twenty percent of MNNG-induced intestinal carcinomas harbor Paneth cells. The neoplastic Paneth cells in experimental carcinomas may differentiate from uncommitted cells in the deeper portion of the crypt.