Fig. 2: Knockdown of MG53 leads to a hyper-inflammatory response to viral infection.

a shRNA lentivirus was used to create stable sh-control and sh-MG53 knockdown THP1 cells. THP1 protein lysates (40 µg) were loaded for western blot and probed for MG53 and GAPDH expression. rhMG53 (0.1 ng) was loaded as a positive control (data representative of three independent experiments). b sh-control and sh-MG53 cells were infected with SeV-GFP (MOI 2) for 24 h. Cells were then analyzed for GFP+ signal via flow cytometry to determine the percentage of infected cells. There were no differences in infections rates between sh-control and shMG53 cells following SeV. c Quantification of percentage of SeV-GFP-positive cells (data representative of four independent experiments; mean ± SD; n.s. means nonsignificant, p = 0.9138; two-sided unpaired t test). d, e PMA-differentiated sh-control and sh-MG53 THP1 cells were infected with SeV (MOI 5) for 24 or 48 h. Supernatants were collected and assayed for cytokine secretion via ELISA. Knockdown of MG53 results in significant increase in IFNβ and IL-1β secretion 24 and 48 h after infection with SeV. Graphs depict representative data from three independent experiments, each performed in triplicate (mean ± SD; ***p = 0.0006, ****p < 0.0001, ND = not detected; two-sided unpaired t tests).