Phagocytosis of filamentous targets

人体抵御外来威胁和清理自身细胞碎片的策略是隔离并摧毁它们。这是由免疫系统中的特殊细胞，吞噬细胞，通过一个叫做吞噬作用的过程来完成的。在吞噬过程中，吞噬细胞吞噬它们的目标，然后在细胞内降解。为了实现它们的功能，吞噬细胞必须处理不同成分、形状和质地的目标。目前，许多吞噬作用的研究都集中在靶标的组成上。然而，对靶标的物理性质如何影响吞噬过程知之甚少。特别令人感兴趣的是长纤维靶标，因为研究表明，微生物和这种形式的惰性颗粒都不容易被吞噬细胞吸收。因此，这些类型的目标有利于产生毒性作用，就像石棉和玻璃纤维的情况一样，或者是感染细菌的持久性，比如UPEC大肠杆菌。我研究的主要目的是研究为什么丝状目标，包括细菌和惰性颗粒，成为吞噬的障碍。我们期望该项目将有助于更好地了解控制吞噬作用的机制以及病原体利用的逃避这一过程的方式。我们也期望对石棉纤维毒性背后的机制有更好的了解。从技术角度来看，这些发现可以为设计更安全的纤维工程材料（如纳米管）提供知识，这些材料具有巨大的技术和经济潜力。

The body's strategy to protect against foreign threats and clean its own cellular debris is to isolate and destroy them. This is carry out by specialized cells from the immune system, phagocytes, through a process called phagocytosis. During phagocytosis, phagocytes engulf and eat their targets, which are then degraded inside the cell. To fulfill their function, phagocytes must process targets of different composition, shape and texture. Today, much of phagocytosis research has focused on the composition of the target. However, little is known about how target's physical properties affect the phagocytic process. Of particular interest are long and fibrous targets because studies have shown that both microbes and inert particles of that form can not be easily ingested by phagocytes. Therefore, these type of targets favor toxic effects, as is the case for asbestos and glass fibers, or the persistence of infections bacteria, like UPEC E.coli. The main objective of my research will be to investigate why filamentous targets, both bacterial and inert particles, become a hurdle for phagocytosis. We expect that this project will contribute to a better understanding of the mechanisms that control phagocytosis and the ways utilized by pathogens to escape this process. We also expect to reach a better understanding of the mechanism behind the toxicity of asbestos fibers. From a technological perspective, such findings could contribute knowledge to the design of more safe fibrous engineered materials, like nanotubes, which are of an enormous technological and economical potential.