To investigate the role of TGF-β1 in the enhancement of RuV binding and infection in A549 cells, various TGF-β1 inhibitors were used to suppress the TGF-β1 downstream pathways, including p38 MARK, MEK/ERK1/2 and SMAD2/3, as well as the JNK pathway. Here, MAPK8 is linked to infection.