Upregulation of tetraspanin 8 may contribute to LPSinduced acute lung injury by activation of the MAPK and NF-κB pathways

Purpose: To investigate the effect of tetraspanin8 (Tspan8, also known as TM4SF3 or CO-029) on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and the related signaling pathways.Methods: Treatment with LPS was used to induce lung damage in mice and a lung epithelial cell line. The wet-to-dry weight ratio of lung tissue, hematoxylin and eosin (H&E) staining, and quantification of cytokine concentrations were conducted to validate the model. Enzyme-linked immunosorbent assays (ELISA) and quantitative polymerase chain reaction (qPCR) were used to measure levels of tumor necrosis factor alpha, interleukin (IL)-1β, and IL-6. Tspan8 levels were knocked down using shRNAs. Mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) pathway levels were assessed after LPS-induced injury in this cellular model.Results: Levels of Tspan8 were upregulated in the LPS-induced ALI model. Additionally, LPS treatment of mouse lung epithelial cells resulted in Tspan8 upregulation. Tspan8 knockdown alleviated the effects of LPS on lung epithelial injury by inhibiting the upregulation of MAPK and NF-κB signaling pathways.Conclusion: The upregulation of Tspan8 may promote the progression of ALI.