Nakase Hiroshi, Nishio Akiyoshi, Tamaki Hiroyuki, Matsuura Minoru, Asada Masanori, Chiba Tsutomu, Okazaki Kazuichi
Department of Gastroenterology & Endoscopic Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Inflamm Bowel Dis. 2006 Jan;12(1):62-9. doi: 10.1097/01.mib.0000191671.12229.47.
Mycobacterial avium subspecies paratuberculosis (MAP) infection has been hypothesized as an etiological factor of Crohn's disease (CD). However, the involvement of MAP in the pathophysiology of CD is controversial. The aim of this study is to investigate whether MAP is involved in the pathogenesis of CD with the glutathione S-transferase fusion recombinant protein encoding a portion of insertion element (IS) 900 (IS900-GST), which is specific for MAP.
Serum samples from the patients with CD (n = 50), ulcerative colitis (n = 40), colonic tuberculosis (n = 20), and non-IBD controls (n = 44), were applied for solid-phase enzyme-linked immunosorbent assay (ELISA) to detect antibodies against MAP and Saccharomyces cerevisiae. IS900-GST, which was made by the pGST-4T-2 vector inserted with polymerase chain reaction-amplified IS900DNA, was used as an antigen of MAP. Moreover, we studied the relationship between antibodies against IS900-GST and clinical characteristics.
ELISA showed that the serum level of immunoglobulin G and immunoglobulin A antibodies against IS900-GST (anti-IS900) in patients with CD were significantly higher than those with ulcerative colitis, colonic tuberculosis, and control subjects. The levels of anti-IS900 tended to be higher in CD patients with small intestinal involvement than with colonic involvement alone. Anti-IS900 in patients with penetrating- and stricture-type CD was significantly higher than with inflammatory-type CD. Furthermore, a negative correlation was found between the titer of anti-IS900 and disease duration. Anti-IS900 was not associated with surgical treatment nor was it associated with the use of immunosuppressants. No significant correlation was observed between the serum levels of anti-IS900 and anti-S cerevisiae antibody.
This is the first demonstration of the ELISA system of detecting antibodies against IS900 in IBD patients. MAP could be involved in the pathophysiology of Japanese patients with CD.
鸟分枝杆菌副结核亚种（MAP）感染被认为是克罗恩病（CD）的一个病因。然而，MAP在CD病理生理学中的作用存在争议。本研究旨在利用编码插入元件（IS）900一部分的谷胱甘肽S-转移酶融合重组蛋白（IS900-GST）来研究MAP是否参与CD的发病机制，该蛋白对MAP具有特异性。
收集CD患者（n = 50）、溃疡性结肠炎患者（n = 40）、结肠结核患者（n = 20）和非炎症性肠病对照者（n = 44）的血清样本，采用固相酶联免疫吸附测定（ELISA）检测抗MAP和抗酿酒酵母抗体。将插入聚合酶链反应扩增的IS900DNA的pGST-4T-2载体构建的IS900-GST用作MAP的抗原。此外，我们研究了抗IS900-GST抗体与临床特征之间的关系。
ELISA显示，CD患者血清中抗IS900-GST（抗IS900）的免疫球蛋白G和免疫球蛋白A抗体水平显著高于溃疡性结肠炎、结肠结核患者及对照者。小肠受累的CD患者抗IS900水平往往高于仅结肠受累者。穿透型和狭窄型CD患者的抗IS900水平显著高于炎症型CD患者。此外，抗IS900滴度与病程呈负相关。抗IS900与手术治疗无关，也与免疫抑制剂的使用无关。抗IS900血清水平与抗酿酒酵母抗体之间未观察到显著相关性。
这是首次在炎症性肠病患者中建立检测抗IS900抗体的ELISA系统。MAP可能参与日本CD患者的病理生理过程。
