Figure 4

TGF-β controls RSV infection. (a) RSV titer at 24 h post-infection of A549 cells that were infected in the absence or presence of purified TGF-β. (b) RSV titer at 24 h post-infection of A549 cells that were infected in the presence of either control antibody (Ab) or TGF-β neutralizing antibody. For the above experiments, A549 cells were pre-treated with antibodies or purified TGF-β for 2 h prior to RSV infection and it was present during infection. The plaque assay values represent the mean ± standard deviation from three independent experiments.