Retinal neurons transplanted form the iris

Damage to the light-detecting cells of the retina is irreversible and causes blindness. In November 12 online Nature Neuroscience Masatoshi Haruta and colleagues from Kyoto University, Japan show that iris tissue in the adult rat eye can generate photoreceptor specific cells which can be used for retinal transplants and treatment of blindness.

Working on cell cultures, Haruta et al. observed that iris tissue in the adult rat eye — which is embryonically related to the neural retina — could generate cells expressing differentiated neuronal antigens. They showed that adenovirus transfer of the Crx gene (crucial in photoreceptor differentiation) induced the specific antigens for rod photoreceptors in the iris-derived cells, while this effect was not seen in the adult hippocampus-derived neural stem cells.

"Our findings demonstrate a remarkable plasticity of adult iris tissue with potential clinical applications, as autologous iris tissue can be feasibly obtained with peripheral iridectomy," wrote the authors.