Basic study of retinal stem/progenitor cell separation from mouse iris tissue.

We described the possibility of retinal regeneration using a novel and efficient technique for culturing and separating retinal stem/progenitor cells from iris tissue. Immunohistochemical staining of adult agouti mouse iris tissue revealed the presence of nestin/low-affinity neurotrophin receptor p75 (p75(NTR))-positive cells on the endothelium camerae anterioris side. Cultured mouse iris-derived cells contained little or no melanin and were found to be positive for nestin. Most nestin-positive cells were analyzed for the coexpression of p75(NTR) as a cell membrane protein. When the p75(NTR) was used as a marker to sort the cells, we obtained a dense population of nestin-positive cells. Furthermore, the nestin/p75(NTR)-positive cells were able to differentiate into neural retina cells. Thus, this culture and separation technique is useful for obtaining retinal stem/progenitor cells from adult mouse iris tissue and for the efficient production of neural retina cells.