Intestinal epithelial cell exfoliation by caspases

摘要 许多细菌病原体试图粘附或侵入肠上皮细胞（IEC），通常使用 操纵IEC中胞质信号通路的毒力因子。然而，独立选举委员会能够调查 通过使用炎性小体家族中的先天免疫传感器，我们已经证明 炎性小体可以通过检测细菌分泌系统的异常易位来检测细菌分泌系统的活性。 细菌鞭毛蛋白、杆状和针状蛋白。 炎性小体主要在巨噬细胞中进行研究，其中活性半胱天冬酶-1首次被证明是 将pro-IL-1β和pro-IL-18切割成其成熟和释放形式。最近发现半胱天冬酶-1可以切割 第三种蛋白质，gasdermin D，它在质膜上形成一个孔，引起程序性溶解细胞 死亡或焦亡。caspase-1在其他细胞类型中的功能现在开始被研究，这些 可能与其在巨噬细胞中的功能略有不同。在这方面，最近在IEC中， 显示出驱动受损IEC的剥落，将其喷射到肠腔中。 Caspase-1是caspase家族的创始成员。胱天蛋白酶通常被认为是 无论是凋亡还是炎症，然而近年来，许多跨类的相互作用已经被发现。 演示。在这里，我们研究了半胱天冬酶-1如何保护IEC，以及其他正常凋亡的IEC。 胱天蛋白酶也参与剥落。我们将研究先天免疫炎性体传感器， 细菌感染期间的脱落，以及不同的先天免疫细胞如何协调它们的活动， 促进IEC剥落。

ABSTRACT Many bacterial pathogens attempt to adhere to or invade intestinal epithelial cells (IECs), often using virulence factors that manipulate cytosolic signaling pathways in the IEC. However, IECs are able to survey their cytosol by using innate immune sensors in the inflammasome family. We have shown that inflammasomes can detect the activity of bacterial secretion systems by detecting aberrant translocation of bacterial flagellin, rod, and needle proteins. Inflammasomes have largely been studied in macrophages, where active caspase-1 was first shown to cleave pro-IL-1β and pro-IL-18 to their mature and released forms. Caspase-1 was recently shown to cleave a third protein, gasdermin D, which forms a pore in the plasma membrane that causes programmed lytic cell death, or pyroptosis. The function of caspase-1 in other cell types is now beginning to be studied, and these may be slightly different from its function in macrophages. In this regard, in IECs inflammasomes were recently shown to drive exfoliation of the compromised IEC, ejecting it into the gut lumen. Caspase-1 is the founding member of the larger caspase family. Caspases are normally considered as either apoptotic or inflammatory, however in recent years many interactions across classes have been demonstrated. Here we examine how IECs are defended by caspase-1, but also that other normally apoptotic caspases are also involved in exfoliation. We will study the innate immune inflammasome sensors that drive exfoliation during bacterial infection, and also how different innate immune cells coordinate their activities to promote IEC exfoliation.