Abstract
Purpose: :
Retinal progenitor cells (RPCs) are immature precursors that can differentiate into retinal neurons including photoreceptors. Recently, it has been reported that bone marrow–derived cells may also be capable of differentiation into cells of CNS lineage, including retinal neurons. We compared these two cell types to evaluate their potential as a source of cells for retinal transplantation.
Methods: :
Marrow stromal cells (MSCs) and macrophages were isolated from EGFP (Enhanced Green Fluorescence Protein) mice. MSCs were cultured with BDNF, NGF and bFGF to induce neuronal differentiation. RPCs were cultured under the same conditions, or with 10% fetal bovine serum. Neuronal marker expression was examined and compared between MSCs and RPCs. MSCs, macrophages and RPCs were also cultured with explanted retinas from rho –/– mice to study their potential for retinal integration.
Results: :
MSCs expressed neuronal and retina specific makers by RT–PCR and immunocytochemistry. Both types of cells also migrated into retinal explants and expressed NF200, GFAP, PKC–α and recoverin. RPCs were found to express rhodopsin, a photoreceptor marker we never detected in MSCs. Bone marrow derived–macrophages differentiated soley into microglia in the explanted retina.
Conclusions: :
This study shows that RPCs are likely a preferred cell type for retinal transplantation studies, compared to MSCs. However, MSCs remain an attractive candidate for autologous transplantation.
Keywords: regeneration • retina • differentiation