Figure 5. Increased IL-18 gene and protein expression in retina and optic nerve from DBA/2J mice. A: RT–PCR analysis shows increased IL-18 gene expression in retina from DBA/2J mice at 3 and 6 months old. B: Graphical representation of 4 independent experiments in A normalized with GAPDH loading control (mean±SD). C: Western blot of IL-18 protein expression in retina from DBA/2J mice at 1 to 6 months of age. D: Densitometric analysis of 3 independent experiments from C, using actin as a loading control, revealed significantly higher expression of IL-18 in retina from DBA/2J mice from 4 to 6 months when compared with 1 month of age. E: Western blot of IL-18 protein expression in optic nerve from DBA/2J mice at 1 to 6 months of age. F: Densitometric analysis of 3 independent experiments from E, shows increased IL-18 protein expression compared to actin loading control in optic nerve from DBA/2J mice by 5 months of age. Statistical analyses for this experiment was performed using ANOVA with the Scheffé multiple comparison test (the asterisk indicates a p<0.05).