Human RPE Stem Cell-Derived RPE Preserves Photoreceptors in the Royal College of Surgeons Rat: Method for Quantifying the Area of Photoreceptor Sparing

Abstract

RPESC-RPE transplantation preserves RCS photoreceptor cells. The photoreceptor cell contour maps readily convey the extent of rescue across the eye. The consistent alignment and quantification of results using this method allow the application of other downstream statistical analyses and comparisons to better understand transplantation therapy in the eye.

The Developmental Stage of Adult Human Stem Cell-Derived Retinal Pigment Epithelium Cells Influences Transplant Efficacy for Vision Rescue

“…To quantify anatomic preservation, ONL photoreceptor nuclei were counted across the retina, with spatial distribution plotted as the ONL number along both superior-inferior and nasal-temporal axes (Davis et al., 2016). Transplants survived, and most cells engrafted were found aligned along the rat RPE layer, with occasional clumps of cells also observed (Figure S4).…”

“…Photoreceptor ONL quantification was accomplished by counting columns of photoreceptor nuclei across the retinal length at 100–150 μm intervals from six adjacent positions, as described (Davis et al., 2016). …”

“…RPESCs are poised to generate highly pure cultures of RPE progeny (RPESC-RPE) displaying characteristics of native RPE (Blenkinsop et al., 2015). We previously reported that subretinal transplantation of RPESC-RPE in the Royal College of Surgeons (RCS) rat prevents the loss of photoreceptor cells that occurs in these animals (Davis et al., 2016). Here, we report that transplantation of RPESC-RPE effectively rescued vision (i.e., prevented vision loss that normally occurs in the RCS rat) in a differentiation stage-dependent manner.…”

Screening and optimization of potential injection vehicles for storage of retinal pigment epithelial stem cell before transplantation

“…They are also prone to tumour formation and immune rejection (Lee, Tang, Rao, Irving, & Wu, ; Xian & Huang, ) and therefore could potentially cause safety and long‐term cell survival concerns (Carr et al, ; Diniz et al, ; Lu et al, ; Nakano‐Okuno, Borah, & Nakano, ; Westenskow et al, ). A newer source of human RPE cell is the adult RPESCs, which are not tumorigenic (Salero et al, ) and show great potential to preserve vision based on preclinical studies (Blenkinsop et al, ; Davis et al, ; Davis et al, ; Stanzel et al, ).…”

“…Stanzel et al () demonstrated the feasibility of in vivo subretinal transplantation of a preformed monolayer of polarized, adult RPESC‐derived RPE cells on a permanent substrate in the rabbit. Following, it was shown that subretinal injection of a suspension of RPESC‐RPE cells is efficacious at preventing vision loss in the Royal College of Surgeons rat model of retinal degeneration (Davis et al, ). Notably, a particular intermediate stage of the RPESC‐RPE cell product was found to be most efficacious at preserving vision in this model (Davis et al, ).…”