Fig. 2.

Conditioned medium induced differentiation in retinal progenitors in low-density cultures. Retinal progenitors plated at a density of 1 × 10⁴ cells/cm² were treated with RPE-conditioned medium (100%, 50%, 25%, 12.5%) and analyzed on days 1–3 for differentiation. Seven hundred to 800 cells were scored for phenotypic analysis by phase microscopy/photomicrographs and analysis in a blind study by two investigators. Emerging phenotype grouped as progenitors, multipolars (ganglion and amacrine cells), and photoreceptors (rods and cones) as described in “Materials and methods” section and results. This figure is the composite of data collected. Note that no significant differences were noted on day 1. Note on day 2 that a drop in the number of progenitors is seen in cells treated with 50% conditioned medium accompanied by a simultaneous increase in the number of photoreceptors reaching as high as 70%. There was a slight increase in the number of cells with multipolar neuronal phenotype in cells exposed to 100% conditioned medium. On day 3, the number of cells with photoreceptor phenotype in cells treated with 50% conditioned medium was close to 90% with a simultaneous drop in the number of progenitors