Department of Internal Medicine, Hanyang University Guri Hospital, Guri, South Korea.
Infect Immun. 2014 Jun;82(6):2239-46. doi: 10.1128/IAI.01513-13. Epub 2014 Mar 18.
We evaluated whether a simplified human microbiota consortium (SIHUMI) induces colitis in germfree (GF) 129S6/SvEv (129) and C57BL/6 (B6) interleukin-10-deficient (IL-10(-/-)) mice, determined mouse strain effects on colitis and the microbiota, examined the effects of inflammation on relative bacterial composition, and identified immunodominant bacterial species in "humanized" IL-10(-/-) mice. GF wild-type (WT) and IL-10(-/-) 129 and B6 mice were colonized with 7 human-derived inflammatory bowel disease (IBD)-related intestinal bacteria and maintained under gnotobiotic conditions. Quantification of bacteria in feces, ileal and colonic contents, and tissues was performed using 16S rRNA gene selective quantitative PCR. Colonic segments were scored histologically, and gamma interferon (IFN-γ), IL-12p40, and IL-17 levels were measured in supernatants of unstimulated colonic tissue explants and of mesenteric lymph node (MLN) cells stimulated by lysates of individual or aggregate bacterial strains. Relative bacterial species abundances changed over time and differed between 129 and B6 mice, WT and IL-10(-/-) mice, luminal and mucosal samples, and ileal and colonic or fecal samples. SIHUMI induced colitis in all IL-10(-/-) mice, with more aggressive colitis and MLN cell activation in 129 mice. Escherichia coli LF82 and Ruminococcus gnavus lysates induced dominant effector ex vivo MLN TH1 and TH17 responses, although the bacterial mucosal concentrations were low. In summary, this study shows that a simplified human bacterial consortium induces colitis in ex-GF 129 and B6 IL-10(-/-) mice. Relative concentrations of individual SIHUMI species are determined by host genotype, the presence of inflammation, and anatomical location. A subset of IBD-relevant human enteric bacterial species preferentially stimulates bacterial antigen-specific TH1 and TH17 immune responses in this model, independent of luminal and mucosal bacterial concentrations.
我们评估了简化的人类微生物群联合体（SIHUMI）是否会在无菌（GF）129S6/SvEv（129）和 C57BL/6（B6）白细胞介素-10 缺陷（IL-10（-/-））小鼠中诱导结肠炎，确定了小鼠品系对结肠炎和微生物群的影响，研究了炎症对相对细菌组成的影响，并在“人源化”IL-10（-/-）小鼠中鉴定了免疫显性细菌物种。无菌野生型（WT）和 IL-10（-/-）129 和 B6 小鼠用 7 种源自炎症性肠病（IBD）的肠道细菌定植，并在无菌条件下维持。使用 16S rRNA 基因选择性定量 PCR 对粪便、回肠和结肠内容物以及组织中的细菌进行定量。对结肠段进行组织学评分，并测量未刺激的结肠组织外植体和通过单个或聚集细菌菌株的裂解物刺激的肠系膜淋巴结（MLN）细胞上清液中的伽马干扰素（IFN-γ）、IL-12p40 和 IL-17 水平。相对细菌物种丰度随时间而变化，并且在 129 和 B6 小鼠、WT 和 IL-10（-/-）小鼠、腔和粘膜样本以及回肠和结肠或粪便样本之间存在差异。SIHUMI 诱导所有 IL-10（-/-）小鼠结肠炎，129 小鼠结肠炎更具侵袭性，MLN 细胞激活更明显。大肠杆菌 LF82 和 Ruminococcus gnavus 裂解物诱导了体外主要效应物 MLN TH1 和 TH17 反应，尽管细菌粘膜浓度较低。总之，这项研究表明，简化的人类细菌联合体可诱导 ex-GF 129 和 B6 IL-10（-/-）小鼠结肠炎。个体 SIHUMI 物种的相对浓度由宿主基因型、炎症的存在和解剖位置决定。一组与 IBD 相关的人类肠道细菌物种在该模型中优先刺激细菌抗原特异性 TH1 和 TH17 免疫反应，而与腔和粘膜细菌浓度无关。
