Abstract
Abstract: :
Purpose: A growing body of evidence suggests that glia besides supporting neurogenesis can themselves act as neural progenitors (Goldman 2003, TINS 26:590–596). Recent evidence suggests that Müller glia can generate neurons in response to injury (Fischer et al. 2002 J.Neuroscience, 22: 9387–9398). Here we report the characterization of Müller glia from uninjured post natal rat retina for progenitor/stem cell properties. Methods: We isolated and purified Müller cells from the retina of postnatal 10 rats as previously described (Hicks and Courtois1990, Exp. Eye. Res., 51: 119–29). The purity of the Müller glia was analyzed by immunocytochemical and RT–PCR analyses of Müller cell markers. The isolated Müller cells were exposed to EGF and FGF2 for 5–7 days. After 5–7 days they were analyzed for BrdU incorporation and expression of progenitor markers by immunocytochemocal and RTPCR analyses. To check the multipotentiality, growth factor exposed Müller cells were cultured in the presence of FBS for another 5–7 days and analyzed for the expression of differentiation markers. Results: The purified Müller cells expressed vimentin, GS and CRALBP. Upon exposure to growth factor, they formed neurospheres within 12 hrs. These neurospheres incorporated BrdU and expressed progenitor markers, nestin and Notch1. Primary neurospheres when dissociated and plated again in growth factors containing medium formed secondary neurospheres suggesting self renewal potential. Conclusions: Our data suggest that Müller glia possess the ability to proliferate and form neurospheres in the presence of EGF and FGF2. In addition, our preliminary results suggest that like other stem cells, cells derived from Müller glia, possess self renewal and neural stem progenitor properties.
Keywords: retinal development • proliferation • cell death/apoptosis