BM-MSCs support MV infection ex vivo and act as viable virus producing units. BM-MSCs were infected with MV-NSe-GFP at a range of MOIs, and assessed at 24-hour time points. (A) Representative images taken (Nikon Eclipse; TS100; ×20 objective) at 48 hours postinfection (hpi) at MOI 1.0 demonstrating (i) GFP positivity within multinucleate syncytia (uninfected cells as control) and (ii) cell surface MV-H glycoprotein expression (infected, isotype stained cells shown as negative control. Additional negative control was performed on uninfected cells (data not shown). (B) MTS colorimetric assay performed on infected BM-MSCs at 24-hour time points after infection for a range of MOIs. Mean values from 2 independent experiments carried out in at least triplicate are shown as a percentage of the mean values from uninfected controls. (C) Graph shows measles virus nucleocapsid (MV-N) RNA production by infected BM-MSCs at 24-hour time points postinfection with MOI of 1.0 (i) and at 48 hours postinfection for a range of MOIs (ii). Mean ± SEM. N = 3. (D) Graphs show TCID₅₀ data for MV-infected BM-MSCs at 24-hour time points postinfection with MOIs of (i) 0.1, (ii) 1.0, and (iii) 2.0, performed on cell lysates and supernatants. For supernatants, all time points postinfection were tested, with virus only detectable at 48 hpi for all conditions. Mean ± SEM. N = 3 to 5. (E) Graphs show TCID₅₀ data for BM-MSCs infected with MOI of 1.0 and cultured in the presence or absence of FIP. Data are for (i) 24 hpi (P = .4), (ii) 48 hpi (P = .25), and (iii) 72 hpi (*P = .05) and are shown as mean ± SEM. N = 3 to 5.