Injectable polymeric nanosheets for subretinal cell delivery

Age-related macular degeneration (AMD) is one of the major ophthalmic diseases that cause visual impairment and blindness. Although transplantation of autologous peripheral cells has been attempted by injecting cell suspensions, limited visual improvement resulted due to the low viability of the injected cells in the subretinal tissue. We developed micropatterned polymeric nanosheets toward local delivery of retinal pigment epithelial (RPE) cells. The micropatterned nanosheet directed growth and morphogenesis of the RPE cells, and allowed for the injection of an engineered RPE monolayer through syringe needles flexibly into the subretinal space of rat eyes. Such an ultra-thin flexible carrier has the promise of a minimally invasive delivery of organized cellular structures into narrow tissue spaces.