Department of Medicine, Division of Gastroenterology and Hepatology, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
BMC Gastroenterol. 2010 Feb 16;10:19. doi: 10.1186/1471-230X-10-19.
Inflammation and immune activation have repeatedly been suggested as pathogentic factors in irritable bowel syndrome (IBS). The driving force for immune activation in IBS remains unknown. The aim of our study was to find out if the obligate intracellular pathogen Chlamydia could be involved in the pathogenesis of IBS.
We studied 65 patients (61 females) with IBS and 42 (29 females) healthy controls in which IBS had been excluded. Full thickness biopsies from the jejunum and mucosa biopsies from the duodenum and the jejunum were stained with a monoclonal antibody to Chlamydia lipopolysaccharide (LPS) and species-specific monoclonal antibodies to C. trachomatis and C. pneumoniae. We used polyclonal antibodies to chromogranin A, CD68, CD11c, and CD117 to identify enteroendocrine cells, macrophages, dendritic, and mast cells, respectively.
Chlamydia LPS was present in 89% of patients with IBS, but in only 14% of healthy controls (p < 0.001) and 79% of LPS-positive biopsies were also positive for C. trachomatis major outer membrane protein (MOMP). Staining for C. pneumoniae was negative in both patients and controls. Chlamydia LPS was detected in enteroendocrine cells of the mucosa in 90% of positive biopsies and in subepithelial macrophages in 69% of biopsies. Biopsies taken at different time points in 19 patients revealed persistence of Chlamydia LPS up to 11 years. The odds ratio for the association of Chlamydia LPS with presence of IBS (43.1; 95% CI: 13.2-140.7) is much higher than any previously described pathogenetic marker in IBS.
We found C. trachomatis antigens in enteroendocrine cells and macrophages in the small bowel mucosa of patients with IBS. Further studies are required to clarify if the presence of such antigens has a role in the pathogenesis of IBS.
炎症和免疫激活被反复认为是肠易激综合征（IBS）的致病因素。IBS 中免疫激活的驱动力尚不清楚。本研究的目的是确定专性细胞内病原体沙眼衣原体是否参与 IBS 的发病机制。
我们研究了 65 例 IBS 患者（61 名女性）和 42 例（29 名女性）健康对照者，其中排除了 IBS。用单克隆抗沙眼衣原体脂多糖（LPS）和种特异性单克隆抗沙眼衣原体和肺炎衣原体抗体对空肠全层活检和十二指肠及空肠黏膜活检进行染色。我们使用多克隆抗嗜铬粒蛋白 A、CD68、CD11c 和 CD117 分别识别肠内分泌细胞、巨噬细胞、树突状细胞和肥大细胞。
IBS 患者中 89%存在衣原体 LPS，但健康对照组中仅为 14%（p<0.001），且 79%的 LPS 阳性活检也为沙眼衣原体主要外膜蛋白（MOMP）阳性。患者和对照组均未检测到肺炎衣原体染色。90%的阳性活检中可在黏膜肠内分泌细胞中检测到衣原体 LPS，69%的活检中可在黏膜下巨噬细胞中检测到。19 例患者在不同时间点采集的活检显示衣原体 LPS 持续存在长达 11 年。衣原体 LPS 与 IBS 存在的关联的优势比（43.1；95%CI：13.2-140.7）远高于 IBS 中任何以前描述的致病标志物。
我们在 IBS 患者的小肠黏膜中肠内分泌细胞和巨噬细胞中发现了沙眼衣原体抗原。需要进一步研究以阐明这些抗原的存在是否在 IBS 的发病机制中起作用。
