Progenitor Cells from Human Embryonic Retina – Proliferation and Preferential Differentiation into Ganglion Cells

Abstract

Progenitor cells of the retina give rise to 6 principle types of neurons and the Müller glia cells. In the human retina, differentiation starts at around the beginning of the third month of gestation with the appearance of first postmitotic ganglion cells. As histogenesis proceeds, the remaining types of neurones and the Müller glial cells are generated. The precise mechanisms by which multipotent retinal progenitor cells are guided to give rise to the different postmitotic cell types are largely unknown. Here, we describe the isolation and propagation of retinal progenitor cells from human embryos being 7–8 weeks old, during which time the retina is composed of a population of neural-cell-adhesion-molecule-positive neuroepithelial cells. In vitro, the cells responded to the mitogens EGF and FGF-2 and formed neurospheres, indicating their mitotic activity. Withdrawal of the mitogens in combination with plating on laminin-1-coated culture dishes resulted in high numbers of L1-immunoreactive cells with long processes, which are presumably ganglion cells. These observations indicate that the early differentiation of human retinal progenitor cells into ganglion cells in vivo can be reproduced in vitro. Thus, the cell culture developed in the present study is a useful tool to evaluate instructive stimuli involved in the development of additional retinal cell types from the retinal progenitor cells. Knowledge about such stimuli is a prerequisite for a cell replacement therapy in retinopathological diseases.

Engineering Retina from Human Retinal Progenitors (Cell Lines)

“…Aggregate cultures have been generated from dissociated primary retinal tissues from both fetal and adult retina. [48][49][50] The ability to maintain and expand primitive undifferentiated human retinal progenitors in cultures will be valuable in the study of human retinal genes, and possibly could be used for treatment of degenerative retinal diseases.…”

“…These progenitors when grown attached to cytodex beads in the NASA-developed rotating culture vessel system and formed large 3D constructs. 50,51 We realized that until well-defined biocompatible substrates could be generated, we will be unable to test these transplants in an animal model.…”

Mesencephalic human neural progenitor cells transplanted into the neonatal hemiparkinsonian rat striatum differentiate into neurons and improve motor behaviour

“…The isolation and propagation of hNPCs were in accordance with the Ethical Principles for Medical Research involving Human Subjects of the Declaration of Helsinki and were approved by the local ethics committee and that of the University of Rostock. Isolation and propagation of cells were essentially as described for retinal precursors (Andressen et al. 2003).…”