Nielsen B S, Borregaard N, Bundgaard J R, Timshel S, Sehested M, Kjeldsen L
Department of Pathology, Sundby Hospital, Denmark.
Gut. 1996 Mar;38(3):414-20. doi: 10.1136/gut.38.3.414.
In inflammatory and neoplastic disorders of the colon a defect barrier function of the mucosa may result in absorption of bacterial products from the intestinal lumen. These products may further recruit inflammatory cells and thus augment the inflammatory response. A novel lipocalin in neutrophils, neutrophil gelatinase associated lipocalin (NGAL), with the ability to bind bacterial formylpeptides, has been described and therefore it is of interest to investigate the expression of this protein in diseases of the colon. Expression of NGAL was investigated by immunohistochemistry and by mRNA in situ hybridisation in normal colon and in neoplastic and inflammatory colorectal diseases. A very high expression of NGAL was seen in colonic epithelium in areas of inflammation, both in non-malignant epithelium (diverticulitis, inflammatory bowel disease, and appendicitis) as well as in premalignant and malignant neoplastic lesions of the colon. In adenocarcinoma, the NGAL expression was especially abundant in the transitional mucosa and in the superficial ulcerated area. On the other hand, no NGAL expression could be detected in lymph node metastases from these adenocarcinomas. A weak expression of NGAL in some epithelial cells was only occasionally seen in normal colon. In conclusion, NGAL synthesis is induced in epithelial cells in inflammatory and neoplastic, colorectal diseases. NGAL may serve an important anti-inflammatory function as a scavenger of bacterial products.
在结肠的炎症性和肿瘤性疾病中，黏膜屏障功能缺陷可能导致肠道腔内细菌产物的吸收。这些产物可能进一步募集炎症细胞，从而增强炎症反应。一种存在于中性粒细胞中的新型脂质运载蛋白，即中性粒细胞明胶酶相关脂质运载蛋白（NGAL），具有结合细菌甲酰肽的能力，已有相关描述，因此研究该蛋白在结肠疾病中的表达具有重要意义。通过免疫组织化学和mRNA原位杂交技术，对正常结肠以及肿瘤性和炎症性结直肠疾病中NGAL的表达进行了研究。在炎症区域的结肠上皮中，无论是非恶性上皮（憩室炎、炎症性肠病和阑尾炎）还是结肠的癌前和恶性肿瘤病变，均可见NGAL的高表达。在腺癌中，NGAL表达在移行黏膜和浅表溃疡区域尤为丰富。另一方面，在这些腺癌的淋巴结转移灶中未检测到NGAL表达。在正常结肠中，仅偶尔在一些上皮细胞中见到NGAL的弱表达。总之，在炎症性和肿瘤性结直肠疾病的上皮细胞中可诱导NGAL合成。NGAL作为细菌产物的清除剂，可能发挥重要的抗炎作用。
