Schönrich Günther, Raftery Martin J
Institute of Medical Virology, Helmut-Ruska-Haus, Charité - Universitätsmedizin Berlin , Berlin , Germany.
Front Immunol. 2016 Sep 19;7:366. doi: 10.3389/fimmu.2016.00366. eCollection 2016.
Neutrophils are the most numerous immune cells. Their importance as the first line of defense against bacterial and fungal pathogens is well described. In contrast, the role of neutrophils in controlling viral infections is less clear. Bacterial and fungal pathogens can stimulate neutrophils extracellular traps (NETs) in a process called NETosis. Although NETosis has previously been described as a special form of programmed cell death, there are forms of NET production that do not end with the demise of neutrophils. As an end result of NETosis, genomic DNA complexed with microbicidal proteins is expelled from neutrophils. These structures can kill pathogens or at least prevent their local spread within host tissue. On the other hand, disproportionate NET formation can cause local or systemic damage. Only recently, it was recognized that viruses can also induce NETosis. In this review, we discuss the mechanisms by which NETs are produced in the context of viral infection and how this may contribute to both antiviral immunity and immunopathology. Finally, we shed light on viral immune evasion mechanisms targeting NETs.
中性粒细胞是数量最多的免疫细胞。它们作为抵御细菌和真菌病原体的第一道防线的重要性已得到充分描述。相比之下，中性粒细胞在控制病毒感染中的作用尚不清楚。细菌和真菌病原体可通过一种称为中性粒细胞胞外诱捕网形成（NETosis）的过程刺激中性粒细胞形成胞外诱捕网（NETs）。尽管NETosis此前被描述为一种特殊形式的程序性细胞死亡，但存在一些NET生成形式并不会以中性粒细胞的死亡告终。作为NETosis的最终结果，与杀菌蛋白复合的基因组DNA从中性粒细胞中排出。这些结构可以杀死病原体，或者至少防止它们在宿主组织内局部扩散。另一方面，NETs的过度形成会导致局部或全身损伤。直到最近，人们才认识到病毒也能诱导NETosis。在这篇综述中，我们讨论了在病毒感染的背景下NETs产生的机制，以及这如何对抗病毒免疫和免疫病理学都有所贡献。最后，我们阐明了针对NETs的病毒免疫逃逸机制。
