Karl Engelsberg

Purpose: To study early signs of neuronal and glial differentiation in the human embryonic retina. Materials and Methods: 6.5-to 8-week-old human embryos were obtained from elective abortions. The neuroretinas were kept in culture as full-thickness sheets for 7-42 days. Results: The control retinas consisted of a neuroblast cell layer and a thin marginal zone. Most explants displayed presence of retinal lamination, but also contained regions of disorganization. Vimentin labeling showed vertically arranged Müller cells in all explants. Recoverin-labeled photoreceptors appeared in explants kept 14 days and longer. By labeling with antibodies against PKC and parvalbumin, rod bipolar cells and amacrine cells could be seen in explants kept for 42 days in culture.Conclusions: We have shown that the embryonic full-thickness neuroretina can survive in a culture environment for at least 6 weeks, and can develop several types of the retina-specific neuronal and glial cells.