PCNA and infection: Quantification of dissociated retinal organoids confirmed that percentages of GFP+PCNA+ double labeled cells were reduced significantly from 52.7 ± 8.0% for LV-GFP infection to 9.0 ± 3.8% and 2.0 ± 1.9% for LV-AEP and LV-NEP infections, respectively (Figure 2F).