Differentiation and transplantation of pigmented epithelial cells from the eye with homebox gene transfer

点击翻译按钮获取中文摘要

To evaluate if the ciliary body possesses any ability to transdifferentiate into neural retina, we cultured the pigment epithelial cells of ciliary bodies of adult rats. The ciliary tissues were separated from the eyes and were placed onto the dishes in an orientation that the epithelial side was down. Cultured in the serum free medium containing basic fibroblast growth factor, many cells migrated out from the ciliary tissues and proliferated as monolayered cells. Immunocytochemical analysis revealed that majority of these cells expressed the nestin, the marker for undifferentiated neural cells.Some of the cells showed the neuronal shape with thin processes after they were induced to differentiate in the medium known to promote neural differentiation. To confirm that these cells really acquired the neural phenotypes, we examined the expression of the mature neuronal or glial markers.Immunocytochemical analysis revealed that these cells contained immunoreactive cells for the neurofilament 200 or the glial fibrilary acidic protein, but not for the opsin, the photoreceptor marker. To determine if these ciliary cells could acquire the photoreceptor phenotypes when genetically engineered, we constructed adenovirus carrying either Crx or GFP(Green Fluorescein Protein)gene. When the pigmented cpithelial cells of ciliary bodies were infected with adenovirus carrying Crx gene and were put under the condition that is known to promote neural differentiation, some of the cells acquired immunoreactivity against the opsin. However, infection with adenovirus carrying GFP gene could not acquire the opsin positive cells. This finding shows that the epithelial cells of adult rat ciliary bodies have potential to transdifferentiate into the photoreceptor cells with the induction of Crx homeobox gene.