Abstract
Purpose: :
Isolation and cultivation of progenitor cells from the adult human ciliary epithelium (CE) and retina may have a future potential in cell-based therapy of retinal diseases. Recently, the concept of CE as a niche for retinal stem cells in humans has been challenged (Moe et al., 2009; Cicero et al., 2009). In the present study, we investigated whether adherent cultivation could effectively expand neural progenitors from the adult human CE and peripheral retina (PR), and their potential for neural differentiation.
Methods: :
The PR and CE were dissected from adult post-mortem donor eyes after approval by the Regional Committees for Medical and Health Research Ethics. The tissue was dissociated into single cells and cultivated as 1) adherent cells with 1% FCS + EGF/FGF or 2) as spheres with EGF/FGF and no serum. Differentiation was performed with removal of growth factors and 3% FCS. Fixed cells were studied by immunocytochemistry, quantitative RT-PCR, and scanning/transmission electronmicroscopy.
Results: :
When cultivated under adherent conditions cells with an elongated morphology from both the adult human PR and CE could be expanded for several passages. Our preliminary data show that at P3, 54% of the PR and 74% of the CE cells stained positive for nestin, a marker of neural progenitors. None of the PR cells contained pigment, while 21% of the nestin-positive CE cells contained pigment. Both adherently cultivated PR and CE cells could form secondary spheres after removal of FCS. After induced differentiation, both PR and CE progenitors differentiated into cells with neuronal properties.
Conclusions: :
Cells with properties of neural progenitors, isolated from both the adult human peripheral retina and ciliary body epithelium, could be effectively isolated and expanded using adherent cultivation.
Keywords: regeneration • retina • ciliary body