Mucosal immune responses in the inductive lymphoid tissues of the intestine begin with uptake of particulate antigens, including components of the gut microbiota by specialized antigen sampling M cells. M cells represent a distinct lineage of enterocytes that arise from crypt stem cells in response to the cytokine receptor of NF-κB ligand (RANKL). Full differentiation of M cells requires the transcription factor Spi-B to yield mature M cells that express multiple receptors for bacteria including glycoprotein 2. M cell differentiation can be recapitulated in vitro using three-dimensional enteroid cultures of primary intestinal stem cells supplemented with RANKL. This article summarizes the current knowledge about the genesis of intestinal M cells and highlights some of the remaining unanswered questions about this enigmatic cell type.

中文翻译：

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肠道 M 细胞：不倦的肠道微生物群采样器。

肠道诱导性淋巴组织中的粘膜免疫反应始于颗粒抗原的摄取，包括通过专门的抗原采样 M 细胞摄取肠道微生物群的成分。M 细胞代表了一种独特的肠细胞谱系，这些肠细胞起源于隐窝干细胞，以响应 NF-κB 配体 (RANKL) 的细胞因子受体。M 细胞的完全分化需要转录因子 Spi-B 来产生成熟的 M 细胞，这些细胞表达多种细菌受体，包括糖蛋白 2。M 细胞分化可以在体外使用补充有 RANKL 的原代肠道干细胞的三维肠样培养物进行概括。本文总结了目前关于肠道 M 细胞起源的知识，并强调了关于这种神秘细胞类型的一些尚未解决的问题。