Lavelle A, Lennon G, O'Sullivan O, Docherty N, Balfe A, Maguire A, Mulcahy H E, Doherty G, O'Donoghue D, Hyland J, Ross R P, Coffey J C, Sheahan K, Cotter P D, Shanahan F, Winter D C, O'Connell P R
University College Dublin, School of Medicine and Medical Science, Dublin, Ireland Centre for Colorectal Disease, Saint Vincent's University Hospital, Dublin, Ireland.
Teagasc, Food Research Centre, Moorepark, Fermoy, County Cork, Ireland.
Gut. 2015 Oct;64(10):1553-61. doi: 10.1136/gutjnl-2014-307873. Epub 2015 Jan 16.
The relevance of spatial composition in the microbial changes associated with UC is unclear. We coupled luminal brush samples, mucosal biopsies and laser capture microdissection with deep sequencing of the gut microbiota to develop an integrated spatial assessment of the microbial community in controls and UC.
A total of 98 samples were sequenced to a mean depth of 31,642 reads from nine individuals, four control volunteers undergoing routine colonoscopy and five patients undergoing surgical colectomy for medically-refractory UC. Samples were retrieved at four colorectal locations, incorporating the luminal microbiota, mucus gel layer and whole mucosal biopsies.
Interpersonal variability accounted for approximately half of the total variance. Surprisingly, within individuals, asymmetric Eigenvector map analysis demonstrated differentiation between the luminal and mucus gel microbiota, in both controls and UC, with no differentiation between colorectal regions. At a taxonomic level, differentiation was evident between both cohorts, as well as between the luminal and mucosal compartments, with a small group of taxa uniquely discriminating the luminal and mucosal microbiota in colitis. There was no correlation between regional inflammation and a breakdown in this spatial differentiation or bacterial diversity.
Our study demonstrates a conserved spatial structure to the colonic microbiota, differentiating the luminal and mucosal communities, within the context of marked interpersonal variability. While elements of this structure overlap between UC and control volunteers, there are differences between the two groups, both in terms of the overall taxonomic composition and how spatial structure is ascribable to distinct taxa.
与溃疡性结肠炎（UC）相关的微生物变化中空间组成的相关性尚不清楚。我们将管腔刷检样本、黏膜活检样本和激光捕获显微切割技术与肠道微生物群的深度测序相结合，以对对照组和UC患者的微生物群落进行综合空间评估。
对来自9名个体的总共98个样本进行测序，平均深度为31,642条 reads，其中包括4名接受常规结肠镜检查的对照志愿者和5名因药物难治性UC接受手术结肠切除术的患者。在四个结直肠位置获取样本，包括管腔微生物群、黏液凝胶层和全层黏膜活检样本。
个体间差异约占总变异的一半。令人惊讶的是，在个体内部，非对称特征向量图分析表明，在对照组和UC患者中，管腔和黏液凝胶微生物群之间存在差异，而结直肠区域之间没有差异。在分类水平上，两个队列之间以及管腔和黏膜区室之间的差异很明显，一小类分类群独特地区分了结肠炎中的管腔和黏膜微生物群。区域炎症与这种空间分化或细菌多样性的破坏之间没有相关性。
我们的研究表明，在明显的个体间差异背景下，结肠微生物群具有保守的空间结构，区分了管腔和黏膜群落。虽然UC患者和对照志愿者之间这种结构的某些元素存在重叠，但两组之间在总体分类组成以及空间结构如何归因于不同分类群方面存在差异。
