Figure 3.

Differential Production of Type 1 IFN by MSCs in Response to Oncolytic MV

(A) IFNα and IFNβ production levels as assessed by ELISA using tissue culture supernatants collected from all MSCs, including primary patient-derived MSCS, at 24 and 48 hpi. Data are expressed as mean ± SEM of two independent experiments (n = 2) with samples measured in duplicates. (B) MV-N mRNA expression levels as assessed by qRT-PCR for 5H cells pre-treated with different concentrations of exogenous IFNβ for 16 h prior to MV infection. Data shown are relative to housekeeping gene GAPDH and normalized to uninfected control cells. Data are expressed as mean ± SEM (n = 3). (C) Cell viability of 5H cells following pre-treatment with IFNβ, and MV infection was assessed by trypan blue exclusion at 30 hpi. hTERT cells were used as a control. Results are reported as a the percentage of cell viability relative to uninfected control cells. Data are expressed as mean ± SEM (n = 3). (D) Immunoblotting of total STAT1, phosphorylated STAT1 (pSTAT1), and IRF9 using cell lysate of uninfected and MV-infected MSCs collected at 24 hpi. β-Tubulin or GAPDH was used as a loading control (n = 3). (E) Densitometry analysis of blot in (D) performed by ImageJ. (F) Immunoblot analysis of pSTAT1 during the time course of MV infection in 5H cells and hTERT cells using cell lysates collected at the indicated time points. Cells stimulated with IFNβ (1,000 U/mL) for 1 h were used as a positive control. Expression of β-tubulin and GAPDH was used as loading controls as indicated.