Figure 1.

Constitutive expression of interferon-stimulated genes measured in measles virus (MV)–resistant glioblastoma (GBM) cells. A) GBM12 and GBM39 cells were infected with MV-NIS (multiplicity of infection [MOI] = 0.1) and virus production measured at 24–96 hours (n = 3). B and C) GBM12 and GBM39 cells were infected with MV-NIS (MOI = 1.0 and 0.1), and cell viability was assessed by MTT assay (n = 3). D) Athymic nude mice were implanted orthotopically with GBM12 or GBM39 cells and received MV therapy (1 × 10⁵ TCID₅₀/mL) once every three days for a total of three or five doses, respectively. E) GBM12 and GBM39 cells were infected with MV-GFP at an MOI of 1.0, and virus entry efficiency was measured by GFP-positive cells assessed by flow cytometry at 24 hours postinfection (n = 2). F) RNA was extracted from uninfected GBM12 and GBM39 cells, and gene expression was analyzed by RNA-Seq. A heat map illustrates the expression of several antiviral interferon-stimulated genes overexpressed in GBM39 cells relative to GBM12. G and H) GBM39 and GBM12 cells were untreated or infected with MV-NIS (MOI = 5), and supernatant was harvested at 12, 24, and 48 hours postinfection (n = 2). IFN-α and IFN-β concentrations were measured by enzyme-linked immunosorbent assay. In vitro experiments were repeated two or more times. A two-sided Student t test was used to determine statistically significant differences. Kaplan-Meier survival curves and log-rank tests were used to obtain median survival times and compare survival between animal groups. Data are presented as the mean and standard deviation (A–C, E, G, and H). GBM = glioblastoma; MOI = multiplicity of infection; MV = measles virus.