美国哈佛医学院Michael C. Carroll和基因泰克公司Shannon J. Turley团队，合作发现了通过小肠淋巴集结（PP）基质的机械诱导调节淋巴细胞迁移和粘膜抗体反应。该研究于2019年10月14日在线发表于《自然—免疫学》。

研究团队报告说小肠PP包含专门的导管系统，该系统引导吸收的液流通过肠道上皮。值得注意的是，PP 纤维母细胞网状细胞（FRC）通过机械敏感离子通道Piezo1对导管流体的流动作出了响应。在表达CCL19的基质上，Piezo1的流体流动中断或遗传缺陷导致血管周FRC和相关的高内皮小静脉发生明显的结构改变。反过来，这会削弱淋巴细胞进入PP和黏膜抗体反应的启动。这些结果确定了导管介导的流体流动在维持PP动态平衡和粘膜免疫中的关键作用。

据悉，FRC及其专门的胶原纤维称为“导管”，形成支持淋巴组织的基本结构单元。在淋巴结中，导管可将组织液和小分子从传入淋巴管传输到淋巴结实质中。但是，导管功能的免疫学作用仍然不清楚。

附：英文原文

Title: Mechanosensing by Peyer’s patch stroma regulates lymphocyte migration and mucosal antibody responses

Author: Jonathan E. Chang, Matthew B. Buechler, Elise Gressier, Shannon J. Turley, Michael C. Carroll

Issue&Volume: 2019-10-14

Abstract: 

Fibroblastic reticular cells (FRCs) and their specialized collagen fibers termed ‘conduits’ form fundamental structural units supporting lymphoid tissues. In lymph nodes, conduits are known to transport interstitial fluid and small molecules from afferent lymphatics into the nodal parenchyma. However, the immunological contributions of conduit function have remained elusive. Here, we report that intestinal Peyer’s patches (PPs) contain a specialized conduit system that directs the flow of water absorbed across the intestinal epithelium. Notably, PP FRCs responded to conduit fluid flow via the mechanosensitive ion channel Piezo1. Disruption of fluid flow or genetic deficiency of Piezo1 on CCL19-expressing stroma led to profound structural alterations in perivascular FRCs and associated high endothelial venules. This in turn impaired lymphocyte entry into PPs and initiation of mucosal antibody responses. These results identify a critical role for conduit-mediated fluid flow in the maintenance of PP homeostasis and mucosal immunity.

DOI: 10.1038/s41590-019-0505-z

Source: https://www.nature.com/articles/s41590-019-0505-z