Abstract
Purpose :
Mice remain the most commonly used species for vision research due to the variety of established genetic, molecular and other tools. In addition, retinal organization and cellular content is highly conserved between mammals. However, due to the small size, high lens-to-vitreous ratio, lack of macula and other differences, murine eye does not allow study of all aspects of cell transplantation, such as dosage, and cell migration. Tree shrew is a non-primate mammal that shares close anatomical and physiological resemblance to the human retina and has been previously used to establish a glaucoma model. In this study we explored two aspects of using tree shrew as a model for cell replacement: the possibility of using tree shrew cells for allotransplantation and the cellular content of tree shrew retina.
Methods :
Immunohistochemistry staining of paraffin embedded tree shrew eye sections were performed with an array of antibodies to determine whether commercially available antibodies could be used to characterize tree shrew retina. To generate tree shrew iPSCs, two type of cells (skin fibroblasts and neural progenitor cells) were derived from adult animals for reprograming. In brief, tree shrew fibroblasts were derived from skin biopsy using explant culture method and neural progenitor cells were isolated from the subventricular zone and cultured in monolayer on poly-D-lysine and laminin-coated plate.
Results :
Commercially available antibodies showed expected immunoreactivity pattern against variety of cell type specific markers (RBPMS, CtBP2, L1CAM, SATB2, Melanopsin, GFAP, RPE65, Recoverin) and axons/dendrites/synaptic (b-actin, Neurofilament, GAP43, MAP2, PSD95, synaptophysin) specific protein in tree shrew retina. Fibroblasts derived from tree shrew skin biopsy showed normal proliferation and exhibit morphological resemblance to that of human and mouse fibroblasts. Isolated neural progenitor cells from tree shrew subventricular zone can be cultured in 2D and displayed similar morphology to that of human and mouse neural progenitor cells.
Conclusions :
Tree shrew retina contains major cell types and RGC subtypes as detected by immunohistochemistry. The specific expression of surface marker L1CAM in RGC layer shows that it can be a good target for cell isolation. Successful derivation and cultures of tree shrew fibroblasts and neural progenitor cells will facilitate the generation of tree shrew iPSC-derived RGCs.
This is a 2020 ARVO Annual Meeting abstract.