Role of HBD2 in innate antiviral function of TNF. A, total
RNA collected from either untreated (UT) or TNF-treated (10 ng/ml TNF
treatment for 16 h) A549 cells transfected with either control or
HBD1-specific siRNA were subjected to RT-PCR to detect HBD1 and GAPDH (loading
control). B, total RNA collected from untreated (UT) and
TNF-treated (10 ng/ml TNF treatment for 8 or 16 h) A549 cells transfected with
either control or HBD2-specific siRNA were subjected to RT-PCR to detect HBD2
and GAPDH. C, A549 cells transfected with either control or
HBD1-specific siRNAs were pretreated with TNF (20 ng/ml) for 20 h, followed by
RSV infection for 36 h. Viral titer at 36 h post-infection was measured by
plaque assay analysis. D, A549 cells transfected with either control
or HBD2-specific siRNA were pretreated with TNF (20 ng/ml) for 20 h, followed
by RSV infection for 36 h. Viral titer at 36 h post-infection was measured by
plaque assay analysis. E, plaque assay values from D were
tabulated to demonstrate the antiviral efficiency of TNF in control and
HBD2-silenced cells. The values are represented as fold decrease in viral
titer following treatment of control and HBD2-silenced cells with TNF. The
plaque assay values for the above experiments are expressed as pfu/ml, and
each value represents the mean ± S.D. for three determinations.