Figure 4. Immortalized Carollia kidney cells respond to surrogate virus infection.

(A) CaPsm-K primary and immortalized cells were transfected with 10 μg of poly(I:C) chemically labelled with rhodamine (pIC-Rho) for 16 hours. Following fixation, cells were stained with antibodies against GAPDH and DAPI and visualized by confocal microscopy. Scale bars represent 25 μm. (B) CaPsm-K cells were transfected with 100ng of poly(I:C) for 8 hours. The upregulation of IFN-β and IFIT1 transcripts was assessed by qPCR. Data are represented as a mean ± SD, n=4 replicates. (C) CaPsm-K cells transfected with 100 ng of poly(I:C) for 8 hours were infected with VSV-GFP (MOI 1) for 16 hours (n=4). Viral replication was visualized by fluorescent microscopy. Scale bars represent 100 μm. (D) GFP signal was quantified using ImageJ (Two-way ANOVA with Šídák’s multiple comparisons test). (E) Representative western blot of VSV-GFP infected cells, where IFIT1, VSV-M and ACTB were probed for. L = molecular weight ladder. (F) CaPsm-K cells transfected with 100 ng of poly(I:C) for 8 hours were infected with MERS-CoV (MOI 0.1) for 48 hours (n=3). Supernatant was collected and TCID₅₀ assay was performed to assess viral titer. (G) Representative western blot of MERS-CoV infected cells, where IFIT1, MERS-CoV nucleocapsid (N), and GAPDH were probed for. L = molecular weight ladder.