Cells were treated with 0.5 × 109/mL PA or 0.25, 0.5, or 1.0 × 109/mL PA-MSHA, and total protein extracted and quantified using BCA assays. Proteins were separated by SDS-PAGE, transferred to PVDF membranes, and incubated with the primary and secondary antibodies listed above. The amount of protein was estimated using the Quantity One software (Bio-Rad, USA) and the relative expression of the target proteins calculated as the amount of the target protein divided by that of GAPDH.