Key Laboratory of Functional Dairy Science, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
College of Horticulture, China Agricultural University, Beijing 100193, China.
Nutrients. 2019 Apr 4;11(4):782. doi: 10.3390/nu11040782.
Intestinal bifidobacteria benefit human health by promoting and modulating the gut flora, and boosting therapeutic efficiency for chronic metabolic diseases and cancer. Recently, strains with high adhesion to intestinal epithelial cells were associated with induction of T-helper 17 (Th17) cells in humans and rodents. Here, two strains with similar adhesive ability but different aggregation properties were investigated for specific immunoregulatory effects, including the underlying cellular pathway, on macrophage and T-regulatory (Treg)/Th17 axis activation in vitro and in the colon of dextran sodium sulfate (DSS)-colitis mice in vivo. In-vitro, the auto-aggregative . strain IF1-11 induced significantly higher IL-6 and lower IL-10 secretion from immune cells, and it induced abundant Th17 cells. The non-aggregating strain IF1-03 induced significantly higher IL-10, less IL-6 and a high proportion of Treg/Th17 cells compared to total T cells. In vivo, orally administered IF1-03 protected DSS-colitis mice via activation of dendritic cells or macrophages and skewing of Treg/Th17 cells, consistent with Treg cell induction in vitro. IF1-03 exopolysaccharides showed a functional recognition pattern similar to IF1-03 for IL-10 cytokine secretion and Treg cell-differentiation induction, both dependent on the toll-like receptor 2-ERK/p38 MAPK-signaling cascade for macrophage activation. We suggest that . exopolysaccharide-associated enterocyte adhesion/aggregation phenotypes determine strain-specific adaptive immune responses in the gut via the macrophage-regulated Treg/Th17 axis.
肠道双歧杆菌通过促进和调节肠道菌群，以及提高慢性代谢性疾病和癌症的治疗效率，有益于人类健康。最近，与人类和啮齿动物肠道上皮细胞高黏附的双歧杆菌菌株与诱导 T 辅助 17（Th17）细胞有关。在这里，研究了两种具有相似黏附能力但聚集特性不同的菌株，以研究其在体外和葡聚糖硫酸钠（DSS）结肠炎小鼠体内结肠中的特定免疫调节作用，包括潜在的细胞途径，对巨噬细胞和 T 调节（Treg）/Th17 轴的激活。在体外，自聚集性. 菌株 IF1-11 可显著诱导免疫细胞中更高水平的 IL-6 和更低水平的 IL-10 分泌，并诱导大量 Th17 细胞。非聚集性菌株 IF1-03 与总 T 细胞相比，可诱导更高水平的 IL-10、更低水平的 IL-6 和更高比例的 Treg/Th17 细胞。在体内，口服给予 IF1-03 通过激活树突状细胞或巨噬细胞和使 Treg/Th17 细胞偏向化，从而保护 DSS-结肠炎小鼠，这与体外诱导 Treg 细胞相一致。IF1-03 胞外多糖表现出与 IF1-03 相似的功能识别模式，可促进 IL-10 细胞因子分泌和 Treg 细胞分化诱导，这两者均依赖于 Toll 样受体 2-ERK/p38 MAPK 信号通路来激活巨噬细胞。我们提出. 与肠上皮细胞黏附/聚集表型相关的胞外多糖决定了双歧杆菌菌株在肠道中的特定适应性免疫反应，这是通过巨噬细胞调节的 Treg/Th17 轴实现的。
