细菌易位穿透血脑屏障的分子机制

Mechanism of Bacterial Traversal across the Blood Brain Barrier

血脑屏障(blood brain barrier,BBB)主要由脑微血管内皮细胞构成,是维持中枢神经系统稳态的重要膜性生物屏障。细菌可通过受体介导的识别和黏附机制入侵微血管内皮细胞或吞噬细胞,随后通过信号转导和炎症反应机制调控胞吞、胞吐和细胞迁移过程,介导细菌的跨细胞、细胞旁和特洛伊木马3种通过途径。该文在综述典型脑膜炎致病菌对BBB结构完整性和通透性调节机制基础上,讨论了沙门氏菌跨BBB感染致病的可能机制,以期为该肠道菌的神经致病性机制研究提供参考。

The BBB (blood brain barrier),composed mainly of specialized brain microvascular endothelial cells,is an important membrane barrier that maintains biochemical homeostasis in the CNS (central nervous system).Bacteria use a variety of different virulence factors that enable them to attach to and invade microvascular endothelial cells or phagocytes through receptor-mediated recognition and adhesion mechanism.Endocytosis,exocytosis,and migration can be manipulated by these bacteria through host cell signaling and inflammatory response mechanisms,which will facilitate traversal of BBB via transcellular passage,paracellular passage and "Trojan horse" mechanism.Based on the crossing mechanism of BBB applied by typical meningitis bacteria,hypothesis of BBB traversal by Salmonella oral infection is proposed which may serve as hints for neuropathogenic mechanism of this enterobacteria.