Western blot
Total protein was extracted from murine lung tissues using Radio Immunoprecipitation Assay (RIPA) lysis buffer (P0013b, Beyotime, Shanghai, China). Protein concentrations of samples were measured using the BCA Protein Analysis kit (23225, Thermo Fisher Scientific, Waltham, MA, USA). Sodium dodecyl sulfate-polyacrylamide gels (8% or 10%) were used to separate protein samples, which were then transferred to polyvinylidene fluoride (PVDF) membranes. Blocked for 1 h at room temperature by 5% dedicated skimmed milk, membranes were then incubated overnight with primary antibodies at 4℃ and then incubated with secondary antibodies for 1 h at room temperature. Protein signals were detected by a Tanon automated chemiluminescence fluorescence image analysis system (5200, Tanon, Shanghai, China) with β -actin as an internal reference. Relative protein expression levels were analyzed by ImageJ software and calculated as gray-scale values with band gray value/internal parameter (β -actin) gray value.