Fig. 6

SARS-CoV-2 spike RBD protein enhanced oxidative stress in LPS-induced ALI. Mice were exposed to LPS with or without SARS-CoV-2 spike RBD-Fc protein for 3 days. A The protein expression levels of HO-1, BIP, p62, GCLM and TXN in the lung tissues were determined by western blot analysis, and the representative results were shown. B The OGG1 expression level in the lung tissues was determined by IHC, and the representative images were shown. OGG1 was used as the maker for the staining of oxidative stress. The left panel, 100×, scale bar = 100 μm; the right panel, 400×, scale bar = 100 μm. C The protein expression levels of AKT, p-AKT, p-ERK1/2 and p-p70S6K in the lung tissues were determined by western blot analysis, and the representative results were shown. D Schematic diagram of SARS-CoV-2 spike RBD protein enhanced severity of LPS-induced acute lung injury. Data are shown as mean ± S.D., *P < 0.05, **P < 0.01, and N.S. indicates not significant