Extended Data Fig. 2: Quantification of cell bodies in the ONL of dystrophic RCS rats at 30 and 240 DPI.

The boundaries of the avascular ONL were determined in transversal sections of representative healthy and dystrophic retinas dissected at 30 DPI (a) and 240 DPI (c) by histochemistry with isolectin GS-IB4 (red) staining retinal and choroidal vessels, combined with cell nuclear staining with bisbenzimide (blue). A clear-cut thinning of the ONL associated with widening of the INL was present at both 30 DPI and 240 DPI. Quantification of the number of cell layers labelled with bisbenzimide in the ONL revealed a massive decrease of the nuclear rows of photoreceptors in all dystrophic retinas (non-injected, P3HT-NP injected or sham Glass-NP injected) already at 30 DPI (4 months-old rats; b), that further progressed at 240 DPI (11 months-old rats; d). Means ± sem are shown together with dots representing the mean value obtained for each animal from 9 samplings (3 samples/field and 3 fields/retina). *** p < 0.001, one-way ANOVA/Bonferroni’s tests. Data are means±sem with superimposed individual experimental points. Sample size (experimental animals) @ 30 DPI: RCS-rdy, n = 13; RCS, n = 13; RCS + P3HT, n = 11; RCS + Glass, n = 14. Sample size (experimental animals) @ 240 DPI: RCS-rdy, n = 9; RCS, n = 9; RCS + P3HT, n = 8; RCS + Glass, n = 10. For exact p values, see Supplementary Table 3. ONL, outer nuclear layer; INL, inner nuclear layer; GCL, ganglion cell layer. Scale bar, 100 µm.