DuPont Nutrition and Health, Kantvik Active Nutrition, 02460 Kantvik, Finland.
World J Gastroenterol. 2012 Aug 28;18(32):4404-11. doi: 10.3748/wjg.v18.i32.4404.
To compare quantities of predominant and pathogenic bacteria in mucosal and faecal samples.
Twenty patients undergoing diagnostic colonoscopy with endoscopically and histologically normal mucosa were recruited to the study, 14 subjects of which also supplied faecal (F) samples between 15 d to 105 d post colonoscopy. Mucosal biopsies were taken from each subject from the midportion of the ascending colon (right side samples, RM) and the sigmoid (left side samples, LM). Predominant intestinal and mucosal bacteria including clostridial 16S rRNA gene clusters IV and XIVab, Bacteroidetes, Enterobacteriaceae, Bifidobacterium spp., Akkermansia muciniphila (A. muciniphila), Veillonella spp., Collinsella spp., Faecalibacterium prausnitzii (F. prausnitzii) and putative pathogens such as Escherichia coli (E. coli), Clostridium difficile (C. difficile), Helicobacter pylori (H. pylori) and Staphylococcus aureus (S. aureus) were analysed by quantitative polymerase chain reaction (qPCR). Host DNA was quantified from the mucosal samples with human glyceraldehyde 3-phosphate dehydrogenase gene targeting qPCR. Paired t tests and the Pearson correlation were applied for statistical analysis.
The most prominent bacterial groups were clostridial groups IV and XIVa+b and Bacteroidetes and bacterial species F. prausnitzii in both sample types. H. pylori and S. aureus were not detected and C. difficile was detected in only one mucosal sample and three faecal samples. E. coli was detected in less than half of the mucosal samples at both sites, but was present in all faecal samples. All detected bacteria, except Enterobacteriaceae, were present at higher levels in the faeces than in the mucosa, but the different locations in the colon presented comparable quantities (RM, LM and F followed by P(1) for RM vs F, P(2) for LM vs F and P(3) for RM vs LM: 4.17 ± 0.60 log(10)/g, 4.16 ± 0.56 log(10)/g, 5.88 ± 1.92 log(10)/g, P(1) = 0.011, P(2) = 0.0069, P(3) = 0.9778 for A. muciniphila; 6.25 ± 1.3 log(10)/g, 6.09 ± 0.81 log(10)/g, 8.84 ± 1.38 log(10)/g, P(1) < 0.0001, P(2) = 0.0002, P(3) = 0.6893 for Bacteroidetes; 5.27 ± 1.68 log(10)/g, 5.38 ± 2.06 log(10)/g, 8.20 ± 1.14 log(10)/g, P(1) < 0.0001, P(2) ≤ 0.0001, P(3) = 0.7535 for Bifidobacterium spp.; 6.44 ± 1.15 log(10)/g, 6.07 ±1.45 log(10)/g, 9.74 ±1.13 log(10)/g, P(1) < 0.0001, P(2) ≤ 0.0001, P(3) = 0.637 for Clostridium cluster IV; 6.65 ± 1.23 log(10)/g, 6.57 ± 1.52 log(10)/g, 9.13 ± 0.96 log(10)/g, P(1) < 0.0001, P(2) ≤ 0.0001, P(3) = 0.9317 for Clostridium cluster XIVa; 4.57 ± 1.44 log(10)/g, 4.63 ± 1.34 log(10)/g, 7.05 ± 2.48 log(10)/g, P(1) = 0.012, P(2) = 0.0357, P(3) = 0.7973 for Collinsella spp.; 7.66 ± 1.50 log(10)/g, 7.60 ± 1.05 log(10)/g, 10.02 ± 2.02 log(10)/g, P(1) ≤ 0.0001, P(2) = 0.0013, P(3) = 0.9919 for F. prausnitzsii; 6.17 ± 1.3 log(10)/g, 5.85 ± 0.93 log(10)/g, 7.25 ± 1.01 log(10)/g, P(1) = 0.0243, P(2) = 0.0319, P(3) = 0.6982 for Veillonella spp.; 4.68 ± 1.21 log(10)/g, 4.71 ± 0.83 log(10)/g, 5.70 ± 2.00 log(10)/g, P(1) = 0.1927, P(2) = 0.0605, P(3) = 0.6476 for Enterobacteriaceae). The Bifidobacterium spp. counts correlated significantly between mucosal sites and mucosal and faecal samples (Pearson correlation coefficients 0.62, P = 0.040 and 0.81, P = 0.005 between the right mucosal sample and faeces and the left mucosal sample and faeces, respectively).
Non-invasive faecal samples do not reflect bacterial counts on the mucosa at the individual level, except for bifidobacteria often analysed in probiotic intervention studies.
比较黏膜和粪便样本中主要和致病细菌的数量。
招募 20 名接受诊断性结肠镜检查且内镜和组织学均正常的患者入组研究，其中 14 名患者还在结肠镜检查后 15 至 105 天之间提供粪便（F）样本。从每位受试者的升结肠中段（右侧样本，RM）和乙状结肠（左侧样本，LM）采集黏膜活检标本。分析包括梭菌 16S rRNA 基因簇 IV 和 XIVab、拟杆菌门、肠杆菌科、双歧杆菌属、阿克曼氏菌（A. muciniphila）、韦荣球菌属、柯林斯氏菌属、普氏真杆菌（F. prausnitzii）和潜在病原体如大肠杆菌（E. coli）、艰难梭菌（C. difficile）、幽门螺杆菌（H. pylori）和金黄色葡萄球菌（S. aureus）等主要肠道和黏膜细菌。用人类甘油醛 3-磷酸脱氢酶基因靶向 qPCR 定量黏膜样本中的宿主 DNA。采用配对 t 检验和 Pearson 相关分析进行统计分析。
在两种样本类型中，最主要的细菌群是梭菌 IV 群和 XIVa+b 和拟杆菌门以及普氏真杆菌（F. prausnitzii）。幽门螺杆菌和金黄色葡萄球菌未检出，艰难梭菌仅在 1 个黏膜样本和 3 个粪便样本中检出。大肠杆菌在两个部位的黏膜样本中均未检出，但在所有粪便样本中均有检出。除肠杆菌科外，所有检测到的细菌在粪便中的含量均高于黏膜，但不同部位的结肠含量相当（RM、LM 和 F 后 P(1)为 RM 与 F 比较，P(2)为 LM 与 F 比较，P(3)为 RM 与 LM 比较：4.17 ± 0.60 log(10)/g，4.16 ± 0.56 log(10)/g，5.88 ± 1.92 log(10)/g，P(1) = 0.011，P(2) = 0.0069，P(3) = 0.9778 用于 A. muciniphila；6.25 ± 1.3 log(10)/g，6.09 ± 0.81 log(10)/g，8.84 ± 1.38 log(10)/g，P(1) < 0.0001，P(2) = 0.0002，P(3) = 0.6893 用于拟杆菌门；5.27 ± 1.68 log(10)/g，5.38 ± 2.06 log(10)/g，8.20 ± 1.14 log(10)/g，P(1) < 0.0001，P(2) ≤ 0.0001，P(3) = 0.7535 用于双歧杆菌属；6.44 ± 1.15 log(10)/g，6.07 ± 1.45 log(10)/g，9.74 ± 1.13 log(10)/g，P(1) < 0.0001，P(2) ≤ 0.0001，P(3) = 0.637 用于梭菌 IV 簇；6.65 ± 1.23 log(10)/g，6.57 ± 1.52 log(10)/g，9.13 ± 0.96 log(10)/g，P(1) < 0.0001，P(2) ≤ 0.0001，P(3) = 0.9317 用于梭菌 XIVa 簇；4.57 ± 1.44 log(10)/g，4.63 ± 1.34 log(10)/g，7.05 ± 2.48 log(10)/g，P(1) = 0.012，P(2) = 0.0357，P(3) = 0.7973 用于柯林斯氏菌属；7.66 ± 1.50 log(10)/g，7.60 ± 1.05 log(10)/g，10.02 ± 2.02 log(10)/g，P(1) ≤ 0.0001，P(2) = 0.0013，P(3) = 0.9919 用于普氏真杆菌（F. prausnitzsii）；6.17 ± 1.3 log(10)/g，5.85 ± 0.93 log(10)/g，7.25 ± 1.01 log(10)/g，P(1) = 0.0243，P(2) = 0.0319，P(3) = 0.6982 用于韦荣球菌属；4.68 ± 1.21 log(10)/g，4.71 ± 0.83 log(10)/g，5.70 ± 2.00 log(10)/g，P(1) = 0.1927，P(2) = 0.0605，P(3) = 0.6476 用于肠杆菌科）。双歧杆菌属的计数在黏膜部位和黏膜与粪便样本之间存在显著相关性（右侧黏膜样本与粪便和左侧黏膜样本与粪便之间的皮尔逊相关系数分别为 0.62，P = 0.040 和 0.81，P = 0.005）。
非侵入性粪便样本不能反映个体水平上的黏膜细菌计数，除了经常在益生菌干预研究中分析的双歧杆菌属。
