KITLG and infection: Furthermore, TUNEL analysis showed that infection with AAV8 control or AAV8-KITL virus did not cause photoreceptor cell death under normal light conditions, but under LD conditions, photoreceptor cell death was less pronounced when AAV8-KITL was used (9 ± 1.6%, n = 6) compared to when control AAV8 was used (40.8 ± 4.5%, n = 6) or the eyes were left uninfected (37.7 ± 5%, n = 6) (Figure 4F,G).