Mucolytic Bacteria With Increased Prevalence in IBD Mucosa Augment In Vitro Utilization of Mucin by Other Bacteria
Mucolytic Bacteria With Increased Prevalence in IBD Mucosa Augment In Vitro Utilization of Mucin by Other Bacteria
复制标题
DOI：
10.1038/ajg.2010.281
复制
发表时间：
2010-11-01
影响因子：
9.8
通讯作者：
Florin, Timothy H. J.
中科院分区：
文献类型：
--
作者：
Png, Chin Wen;Linden, Sara K.;Florin, Timothy H. J.
目的：炎症性肠病（IBD）中粘膜相关细菌增加，这表明可消化内源性粘液底物来源增加的可能性。我们假设，粘液溶解细菌增加IBD，提供更多的基板，以维持nonmucolytic mucosa-associated bacteries.METHODS：粘液溶解细菌的特点是能够降解人类分泌粘蛋白（MUC 2）在纯和混合厌氧培养。采用实时荧光定量PCR方法对46例IBD患者和20例对照组患者的粘膜相关粘液溶解菌进行计数。结果：在克罗恩病（CD）和溃疡性结肠炎（UC）的正常肠上皮细胞中，粘膜相关细菌16 SrRNA基因的表达均明显增加（平均1.9倍），溃疡性结肠炎（UC）的粘膜相关细菌16 SrRNA基因的表达明显增加（平均1.3倍）。我们发现一些粘液溶解细菌的不成比例的增加。在CD和UC的肉眼和组织学正常肠上皮中，平均活泼瘤胃球菌增加了>4倍，扭转瘤胃球菌增加了类似于100倍。对照中最丰富的粘液溶解细菌嗜粘蛋白阿克曼氏菌在CD和UC中减少了许多倍。共培养A.粘蛋白2作为唯一的碳源，导致其丰度减少，而它增加了其他bacterias.CONCLUSIONS：粘液溶解细菌的生长存在于健康的人，在那里他们是一个不可分割的一部分，粘膜相关的细菌财团。不成比例地增加R。gnavus和R.扭矩可以解释IBD中粘膜相关细菌总数的增加。
OBJECTIVES: Mucosa-associated bacteria are increased in inflammatory bowel disease (IBD), which suggests the possibility of an increased source of digestible endogenous mucus substrate. We hypothesized that mucolytic bacteria are increased in IBD, providing increased substrate to sustain nonmucolytic mucosa-associated bacteria.METHODS: Mucolytic bacteria were characterized by the ability to degrade human secretory mucin (MUC2) in pure and mixed anaerobic cultures. Real-time PCR was used to enumerate mucosa-associated mucolytic bacteria in 46 IBD and 20 control patients. Bacterial mucolytic activity was tested in vitro using purified human MUC2.RESULTS: We confirm increased total mucosa-associated bacteria 16S rRNA gene in macroscopically and histologically normal intestinal epithelium of both Crohn's disease (CD) (mean 1.9-fold) and ulcerative colitis (UC) (mean 1.3-fold). We found a disproportionate increase in some mucolytic bacteria. Mean Ruminococcus gnavus were increased >4-fold and Ruminococcus torques similar to 100-fold in macroscopically and histologically normal intestinal epithelium of both CD and UC. The most abundantly detected mucolytic bacterium in controls, Akkermansia muciniphila, was reduced many fold in CD and in UC. Coculture of A. muciniphila with MUC2 as the sole carbon source led to reduction in its abundance while it augmented growth of other bacteria.CONCLUSIONS: Mucolytic bacteria are present in healthy humans, where they are an integral part of the mucosa-associated bacterial consortium. The disproportionate increase in R. gnavus and R. torques could explain increased total mucosa-associated bacteria in IBD.