Monocytes Promote Human Pulmonary Microvascular Endothelial Cells Pyroptosis Under Hypoxia And Reoxygenation

Objective: Co-cultured monocytes and human pulmonary microvascular endothelial cells(HPMEC)under hypoxia and reoxygenation conditions and exploring the effect and mechanism of monocytes on the HPMEC pyroptosis.Methods: Part ?: Detecting the type and amount of inflammatory factors and choosing the expression of monocytes mediate inflammation via NLRP3 and TLR2 inflammatory pathways.Selecting Larger inflammatory pathway intervention object to the follow-up experiments.Part ?: Setting up co-cultured monocytes and HPMEC and Individually cultured HPMEC.Making it reoxygenation for 1h after three hours of hypoxia,or cultured normally.The treatment of hypoxia and reoxygenation was given to co-cultured monocytes and HPMEC.Detecting the expression of caspase-1 from HPMEC and its supernatant IL-1? and IL-18,the index of pyroptosis,in each group after 8h(5h reoxygenation)and 24h(21h reoxygenation).Part ?: According to the result of Part ?,the NLRP3 pathways was chosen.Knocking down NLRP3 gene in monocytes and inhibiting caspase-1 activity in HPMEC respectively,repeated the co-cultured experiment.Then Detecting the pyroptosisic index of HPMEC at each time with the process of Part ?.Results: The activity of HPMEC was significantly reduced after the experiment of anoxia reoxygenation,and more LDH was released,the secretion and expression of IL-1?,IL-18,and caspase-1 were increased markedly after co-culturing monocytes and HPMEC under hypoxia and reoxygenation.Comparatively,the activity of HPMEC was significantly increased,few LDH was released,and the secretion or expression of IL-1?,IL-18,and caspase-1 were reduced markedly after co-culturing experiments with gene knockdown of NLRP3 in monocytes or caspase-1 inhibition in HPMEC,under hypoxia and reoxygenation.All the results were statistically significant.Conclusion: Monocytes can increase the degree of pyroptosis of HPMEC cells under hypoxia and reoxygenation condition.The mechanism may be related to inflammatory factors secreted by monocytes,such as IL-1? and IL-18 act on HPMEC or monocytes pyroptosis with themselves to make pyroptosis of HPMEC.