Čaja Fabián, Stakheev Dmitry, Chernyavskiy Oleksander, Křížan Jiří, Dvořák Jiří, Rossmann Pavel, Štěpánková Renata, Makovický Peter, Makovický Pavol, Kozáková Hana, Vannucci Luca
Laboratory of Immunotherapy, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic.
Department of Cellular Biology, Faculty of Science, Charles University, Prague, Czech Republic.
J Immunotoxicol. 2021 Dec;18(1):37-49. doi: 10.1080/1547691X.2021.1887412.
Germ-free animals (GF) are those without a microbiome since birth. This particular biological model has become one of special interest with the growing evidence of importance of the microbiome in the life, development, adaptation, and immunity of humans and animals in the environments in which they live. Anatomical differences observed in GF compared with conventionally-reared animals (CV) has given rise to the question of the influence of commensal microflora on the development of structure and function (even immunological) of the bowel. Only recently, thanks to achievements in microscopy and associated methods, structural differences can be better evaluated and put in perspective with the immunological characteristics of GF vs. CV animals. This study, using a GF rat model, describes for the first time the possible influence that the presence of commensal microflora, continuously stimulating mucosal immunity, has on the collagen scaffold organization of the colon mucosa. Significant differences were found between CV and GF mucosa structure with higher complexity in the CV rats associated to a more activated immune environment. The immunological data suggest that, in response to the presence of a microbiome, an effective homeostatic regulation in developed by the CV rats in healthy conditions to avoid inflammation and maintain cytokine levels near the spontaneous production found in the GF animals. The results indicated that collagen scaffold adapted to the immune microenvironment; therefore, it is apparent that the microbiome was able to condition the structure of the colon mucosa.
无菌动物（GF）是指自出生起就没有微生物群的动物。随着微生物群在人类和动物生活、发育、适应及免疫过程中的重要性的证据不断增加，这种特殊的生物学模型已成为特别受关注的对象之一。与传统饲养动物（CV）相比，在无菌动物中观察到的解剖学差异引发了共生微生物群对肠道结构和功能（甚至免疫功能）发育的影响这一问题。直到最近，由于显微镜技术及相关方法的进展，结构差异才能得到更好的评估，并与无菌动物和传统饲养动物的免疫学特征联系起来看待。本研究使用无菌大鼠模型，首次描述了持续刺激黏膜免疫的共生微生物群的存在对结肠黏膜胶原支架组织可能产生的影响。在传统饲养大鼠和无菌大鼠的黏膜结构之间发现了显著差异，传统饲养大鼠的结构更复杂，与更活跃的免疫环境相关。免疫学数据表明，作为对微生物群存在的反应，传统饲养大鼠在健康状态下会形成有效的稳态调节，以避免炎症并使细胞因子水平维持在接近无菌动物自发产生的水平。结果表明，胶原支架适应免疫微环境；因此，很明显微生物群能够影响结肠黏膜的结构。
