PDF(Pubmed)
Abstract：
Commensal microbial-host interaction is crucial for host metabolism, growth, development, and immunity. However, research on microbial-host immunity in large animal models has been limited. This study was conducted to investigate the effects of the commensal microbiota on immune function in two model groups: germ-free (GF) and specific-pathogen-free (SPF) piglets. The weight and organ index of the spleen of the GF piglet were larger than those in the SPF piglet (P < 0.05). The histological structure of the red pulp area and mean area of germinal centers were larger in the SPF piglet than in the GF piglet (P < 0.05), whereas the areas of staining of B cells and T cells in the spleen and mesenteric lymph nodes (MLNs) were lower in the GF piglet (P < 0.05). We identified immune-related genes in the spleen and MLNs using RNA sequencing, and used real-time quantitative PCR to analyze the expression of core genes identified in gene set enrichment analysis. The expression levels of genes in the transforming growth factor-β/SMAD3 signaling pathway, Toll-like receptor 2/MyD88/nuclear factor-κB signaling pathway, and pro-inflammatory factor genes IL-6 and TNF-α in the spleen and MLNs were higher in the SPF piglet and in splenic lymphocytes compared with those in the GF and control group, respectively, under treatment with acetic acid, propionic acid, butyric acid, lipopolysaccharide (LPS), or concanavalin A (ConA). The abundances of plasma cells, CD8++ T cells, follicular helper T cells, and resting natural killer cells in the spleen and MLNs were significantly greater in the SPF piglet than in the GF piglet (P < 0.05). In conclusion, the commensal microbiota influenced the immune tissue structure, abundances of immune cells, and expression of immune-related pathways, indicating the importance of the commensal microbiota for spleen and MLNs development and function. In our study, GF piglet was used as the research model, eliminating the interference of microbiota in the experiment, and providing a suitable and efficient large animal research model for exploring the mechanism of \"microbial-host\" interactions.
摘要：
共生微生物-宿主相互作用对宿主代谢至关重要，增长,发展,和豁免权。然而,在大型动物模型中对微生物-宿主免疫的研究一直很有限。本研究旨在研究共生微生物对两个模型组的免疫功能的影响：无菌（GF）和无特定病原体（SPF）仔猪。GF仔猪脾脏重量和脏器指数均年夜于SPF仔猪(P<0.05)。SPF仔猪的红髓面积和生发中心平均面积的组织学结构均大于GF仔猪（P<0.05），而GF仔猪脾脏和肠系膜淋巴结（MLN）中B细胞和T细胞的染色面积较低（P<0.05）。我们使用RNA测序鉴定了脾脏和MLNs中的免疫相关基因，并采用实时定量PCR对基因集富集分析中鉴定出的核心基因进行表达分析。转化生长因子-β/SMAD3信号通路中基因的表达水平,Toll样受体2/MyD88/核因子-κB信号通路,与GF和对照组相比，SPF仔猪和脾淋巴细胞中脾脏和MLN中的促炎因子基因IL-6和TNF-α较高，分别,在用乙酸处理下，丙酸,丁酸,脂多糖（LPS），或伴刀豆球蛋白A（ConA）。大量的浆细胞，CD8++T细胞，滤泡辅助性T细胞,SPF仔猪脾脏和MLNs中的静息自然杀伤细胞明显大于GF仔猪（P<0.05）。总之,共生微生物群影响免疫组织结构，大量的免疫细胞，和免疫相关途径的表达，表明共生微生物对脾脏和MLNs发育和功能的重要性。在我们的研究中,以GF仔猪为研究模型,消除了实验中微生物群的干扰，并为探索“微生物-宿主”相互作用的机制提供了一种合适而高效的大型动物研究模型。
