Institute of General Pharmacology and Toxicology, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany.
Int Rev Cell Mol Biol. 2020;353:211-253. doi: 10.1016/bs.ircmb.2019.12.008. Epub 2020 Jan 27.
Apoptosis, necroptosis and pyroptosis represent three distinct types of regulated cell death forms, which play significant roles in response to viral and bacterial infections. Whereas apoptosis is characterized by cell shrinkage, nuclear condensation, bleb formation and retained membrane integrity, necroptosis and pyroptosis exhibit osmotic imbalance driven cytoplasmic swelling and early membrane damage. These three cell death forms exert distinct immune stimulatory potential. The caspase driven apoptotic cell demise is considered in many circumstances as anti-inflammatory, whereas the two lytic cell death modalities can efficiently trigger immune response by releasing damage associated molecular patterns to the extracellular space. The relevance of these cell death modalities in infections can be best demonstrated by the presence of viral proteins that directly interfere with cell death pathways. Conversely, some pathogens hijack the cell death signaling routes to initiate a targeted attack against the immune cells of the host, and extracellular bacteria can benefit from the destruction of intact extracellular barriers upon cell death induction. The complexity and the crosstalk between these cell death modalities reflect a continuous evolutionary race between pathogens and host. This chapter discusses the current advances in the research of cell death signaling with regard to viral and bacterial infections and describes the network of the cell death initiating molecular mechanisms that selectively recognize pathogen associated molecular patterns.
细胞凋亡、坏死性凋亡和细胞焦亡是三种不同类型的受调控的细胞死亡形式,它们在应对病毒和细菌感染中发挥着重要作用。细胞凋亡的特征是细胞收缩、核浓缩、泡状形成和保持细胞膜完整性,而坏死性凋亡和细胞焦亡则表现为渗透压失衡导致的细胞质肿胀和早期膜损伤。这三种细胞死亡形式具有不同的免疫刺激潜力。在许多情况下, caspase 驱动的凋亡细胞死亡被认为是抗炎的,而两种裂解性细胞死亡方式可以通过将损伤相关分子模式释放到细胞外空间来有效地触发免疫反应。这些细胞死亡方式在感染中的相关性可以通过存在直接干扰细胞死亡途径的病毒蛋白来最好地证明。相反,一些病原体劫持细胞死亡信号途径,对宿主的免疫细胞发起靶向攻击,而细胞死亡诱导时,细胞外细菌可以受益于完整细胞外屏障的破坏。这些细胞死亡方式之间的复杂性和串扰反映了病原体和宿主之间持续的进化竞赛。本章讨论了与病毒和细菌感染有关的细胞死亡信号研究的最新进展,并描述了选择性识别病原体相关分子模式的细胞死亡起始分子机制的网络。