Figure 4.

Functionality and ON-Bipolar Cell-Type Preference of Novel Synthetic Promoters in Post-mortem HREs

(A) Vertical cryosections through the mid-periphery of the human retina transduced with 770En_454P(hGRM6)-mCitrine. The nuclear stain DAPI differentiates the cell layers, the outer nuclear layer (ONL), the inner nuclear layer (INL), and the ganglion cell layer (GCL). In this example, 83% of ON-bipolar cells (OBCs) express the reporter mCitrine. Scale bar, 80 μm. (B) Quantification of the promoter strengths by measuring the fluorescence of immunolabeled mCitrine in expressing OBCs. Statistical analysis by one-way ANOVA with post hoc Tukey HSD test; ∗∗p < 0.01; n.s., p > 0.05, not significant. (C) As in (A), but triple staining allowing distinction between rOBCs and cOBCs. In this example, 66% of OBCs express mCitrine. The magnified inserts show the differential labeling of rOBCs (Gao+, PKCa+) and cOBCs (Gao+, PKCa−). Expression efficacies, after Equation 1, and bipolar cell type preferences, after Equation 2, have been calculated for the given example. Scale bar, 50 μm. (D) Quantification of the overall cOBC preference of promoters 770En_454P(hGRM6) (n = 6) and 407En_454P(hGRM6) (n = 3). Statistical analysis by Welch’s t test; ∗∗p < 0.01. Data are represented as mean ± SD of biological replicates.