Figure 5. Undifferentiated NPSCs exhibited a higher basal level of autophagic signaling, as compared with HL-1 cells. (A) HL-1 cells and undifferentiated NPSCs were infected with dsRed-CVB3 for 24 h, and protein extracts from lysed cells were analyzed for LC3-I and LC3-II levels by western blot analysis. Protein loading was determined by endogenous β-tubulin levels. (B) The relative intensity of LC3-II compared with β-tubulin levels was determined using Image J software. A statistically significant increase (*p < 0.05) in relative LC3-II intensity was observed between Infected and Mock HL-1 cells by ANOVA with Newman-Keuls post-hoc analysis. Also, a greater (although not statistically significant) level of relative LC3-II intensity was observed for Mock NPSCs and Infected NPSCs, as compared with Mock HL-1 cells. No statistical significant difference was observed between Infected HL-1 cells, Mock NPSCs and Infected NPSCs, thus indicating a higher basal level of autophagy in NPSCs regardless of viral infection. (C) No statistical difference was observed for viral titers between Infected HL-1 cells and Infected NPSCs by Student’s t-test (p = 0.0734).