Fig. 1.

IF staining of photoreceptor precursors. The cells at 12 weeks old showed absence of pluripotency marker OCT4 (A) and only a minority of cells expressed the retinal progenitor marker LHX2 (B, B’). Majority of the cultures expressed pan-photoreceptor markers CRX (C, C’), OTX (D, D’), Recoverin (E, E’). In addition, presence of early rod-specific transcription factor NRL (F, F’) and cone-specific markers cone arrestin (G, G’) and opsin M/L (I and I’), but not the RPE cell marker RPE65 (J), nor the bipolar cell marker PKCα (H) is suggestive of commitment to the photoreceptor lineage. Of note, we did not detect the rod marker rhodopsin after 12 weeks of culture (H). Nuclei are labelled with Hoechst 33342 (H33342). Scale bar: 20 µm. The schematic on the left represents the cell resource development process