Abstract
Purpose::
We have reported that rat Müller glial cells can be converted into a neuronal lineage by in vitro aggregate-culture (ARVO 2006). But they didn’t express markers of retina-specific neurons such as photoreceptor cells. It has been previously reported that embryonic stem cells or retinal progenitor cells become retina-specific neurons when transplanted into vitreous space or subretinal space, suggesting that retina-specific environment might be a key requirement for retinal cell development. In this experiment, we tested whether rat Müller glial cells can be converted to photoreceptor cells by subretinal transplantation.
Methods::
Müller glial cells were obtained from 2-week-old green fluorescent protein transgenic rats according to the method previously reported. After reached to subconfluency, they were passaged to non-adhesive coated culture dishes in serum-free defined medium for aggregate-culture. As a control, they were passaged to adhesive culture dishes for monolayer-culture. After 5 days culture, these cells were collected and transplanted into subretinal space of 2-week-old Long-Evans rats. Seven days after aggregate-culture or monolayer-culture, eye balls were fixed and immunostained with an antibody of opsin.
Results::
Aggregate-cultured Müller glial cells expressed a photoreceptor cell-specific marker, opsin. In contrast, monolayer-cultured Müller glial cells didn’t express the marker.
Conclusions::
Rat Müller glial cells can be converted to photoreceptor cells by in vitro aggregate-culture and subsequent transplantation into subretinal space. These results suggest that Müller glial cells might be used as a cell source for photoreceptor cell regeneration in the patients with degenerative retinal diseases such as retinitis pigmentosa.
Keywords: Muller cells • photoreceptors • differentiation