Fig. 2

Protective effect of FTY720 treatment on retinal parenchyma and vascular network (a–c). a Schematic of neuronal and vascular remodeling upon laser-induced injury. The injury is represented by a gap in the RPE and PR, where fluorescein leaks from the choroidal microvasculature. We evaluated the BRB breakdown, discriminating between superficial vasculature by the NFL (superficial and intermediate vascular plexus) and the deep vasculature by PR and RPE (deep vascular plexus and choriocapillaris). b NFL was identified by the striped-pattern in reflectance (back-scattered light). c PR were identified as an increased brightness while focusing into the deeper retina and appearance of the PR mosaic. NFL nerve fiber layer, VP vascular plexuses, GC ganglion cell layer, INL inner nuclear layer, ONL outer nuclear layer, PR photoreceptor layer, RPE retinal pigment epithelium. d, e Kinetics of retinal injury in reflectance in untreated and FTY720-treated mice. The damage was identified as a hypo-reflective circle (≥ 10% lower intensity compared to healthy parenchyma) surrounding a hyper-reflective core (≥ 10% higher intensity compared to healthy parenchyma). d Images show the absence of hypo- or hyper-reflectivity in FTY720-treated retinas on day 14, unlike untreated retinas in which the injury was visible (delimited by magenta dashes). e Quantification of the damaged area of untreated and FTY720-treated retinas after injury (day 0) and on days 1, 4, 7, 10 and 14. Significant differences (****p < 0.0001) between untreated and FTY720-treated mice were determined using a post hoc Bonferroni one-way ANOVA test (n = 8). f, g Angiographs of untreated and FTY720-treated eyes on day 14. Deep leakage was observed only in untreated animals’ angiograms. g Quantification of leakage deep in the retina after injury (day 0) and on days 1, 4, 7, 10 and 14. Significant differences (**p < 0.01 and ****p < 0.0001) between untreated and FTY720-treated mice were determined using a post hoc Bonferroni one-way ANOVA test (n = 8). Day 0 was chosen as the calibrator [NRQ (normalized relative quantification) = 1]. Field of view is ≈425 µm