The small intestine hosts specialized lymphoid structures, the Peyer's patches, that face the gut lumen and are overlaid with unique epithelial cells, called microfold (M) cells. M cells are considered to constitute an important route for antigen uptake in the mucosal immune system. Here, we used intravital microscopy to define immune cell populations, which are in close contact with M cells and potentially sample antigen. We present live evidence that DCs enter M cell pockets and highlight the abundance of mononuclear phagocytes in these structures. Taking advantage of the respective reporter animals, we focused on classical DCs that express Zbtb46 and analyzed how these cells interact with M cells in steady state and sample antigen for T cell activation in the Peyer's patches following challenge.

中文翻译：

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鼠派尔斑驻留树突状细胞与 M 细胞相互作用的活体可视化。

小肠拥有特殊的淋巴结构，即派尔氏淋巴集结，面向肠腔，并覆盖有独特的上皮细胞，称为微褶皱 (M) 细胞。M细胞被认为构成粘膜免疫系统中抗原摄取的重要途径。在这里，我们使用活体显微镜来定义免疫细胞群，这些细胞群与 M 细胞和潜在的样本抗原密切接触。我们提供了 DC 进入 M 细胞袋的活生生的证据，并强调了这些结构中丰富的单核吞噬细胞。利用各自的报告动物，我们重点关注表达 Zbtb46 的经典 DC，并分析这些细胞如何与稳定状态下的 M 细胞相互作用，并在攻击后对派尔氏集结中的 T 细胞活化取样抗原。