大肠杆菌性脑膜炎 z-bo 2020-11-16 340

　　Objective: To investigate whether the supernatant of Lactobacillus rhamnosus (LGG-CM) can block the bacterial meningitis caused by E. coli K1 strain by inhibiting the NF-κB pathway in vitro.

　　Methods: Human brain microvascular endothelial cells (HBMEC) were used to construct an in vitro blood-brain barrier model; immunoblotting was used to study whether LGG-CM could inhibit E. coli K1 from activating the NF-κB pathway; to study LGG through invasion experiments and neutrophil migration experiments -Can CM inhibit bacterial invasion and neutrophil migration; study the expression of adhesion molecule CD44 and tight junction protein ZO-1 by immunoblotting; detect the intracellular distribution of ZO-1 protein by immunofluorescence; use Transwell to establish in vitro blood-brain barrier Model, evaluate the protective effect of LGG-CM on the integrity of the cell barrier through the TEER value and bacterial migration experiments.

　　Result: Western blotting results show that LGG-CM can inhibit E. coli K1 from activating the NF-κB pathway, thereby inhibiting E. coli K1's invasion and neutrophil migration. At the same time, LGG-CM can inhibit E. coli K1 from up-regulating CD44 protein and down-regulating tight junction protein ZO-1. In addition, LGG-CM can significantly slow down the decrease of TEER value and inhibit E. coli K1 from crossing the blood-brain barrier in vitro.

　　Conclusion: In vitro experiments show that LGG-CM can prevent bacterial encephalitis caused by E. coli K1 by inhibiting the activation of NF-κB pathway, blocking E. coli K1 invasion and neutrophil migration, and maintaining the integrity of the blood-brain barrier.