Fig. 3

Wild-type (WT) and C1qa^−/− retina at day 14 (7 days after the end of photo-oxidative damage, PD) (a). b C1qa expression was significantly elevated in WT PD animals compared to WT dim-reared controls between day 8 and day 14, and the expression level decreased across the days of recovery, in concert with TUNEL⁺ photoreceptor cell death (P < 0.05). c-d TUNEL⁺ cells were present in the outer nuclear layer (ONL) of C1qa^−/− and WT retinas, although the rate of cell death was significantly lower in C1qa^−/− retinas (P < 0.05). e-f Photoreceptor row counts were significantly higher in C1qa^−/− compared to WT, in the superior retina (0.5 mm-1.0 mm away from the optic nerve) (P < 0.05). g-h Fewer IBA1⁺ cells were found in the ONL of C1qa^−/− retinas compared to WT, and was statistically significant (P < 0.05). i-j Western blots showed that there was no significant difference in the relative intensity of C3d proteins between C1qa^−/− and WT retinas (P > 0.05). k-l There was a stronger a-wave and b-wave responses in C1qa^−/− animals compared to WT, particularly at higher flash intensities (P < 0.05). m At the highest flash intensity, C1qa^−/− animals had significantly higher a-wave and b-wave amplitudes compared to WT (P < 0.05). n Cone responses were not significantly different in C1qa^−/− and WT animals (P > 0.05). o Comparison of a-wave and b-wave responses at day 7 and 14 showed significantly higher amplitudes in C1qa^−/− retina at day 14. Statistical significance was measured using student t-test and two-way ANOVA followed by post-hoc multiple comparison (N = 6 per group; * represents P < 0.05; NS represents no significance). For representative images, scale bars represent 50 μm