FIGURE 4.

Expression of R345W-Fibulin-3 decreases TER in primary RPE cells. Cell permeability was assessed by monitoring TER in RPE cells once a week for 21 weeks. At the beginning of the 4th week (week-3 on x-axis), RPE cells reached maturity with TER values maximizing between 1,300 and 1,500 Ω cm². In the beginning of the 7th week (week 0 on x-axis), RPE cells were infected with lentivirus with either luciferase-tagged WT-Fibulin-3 (blue), luciferase-tagged R345W-Fibulin-3 (red), or luciferase-tag only (gray) for five consecutive days. At 3 weeks post-infection, TER decreased to approximately 800 Ω cm² in all groups. At 4 weeks post-infection, TER continuously dropped in the mutant group (n = 8) and reached values significantly lower than the WT (n = 8) and tag-only groups (n = 2). (Values are mean ± SEM of individual wells, **p < 0.01).