Chair: P. B. Persson (Berlin, Germany)
|A FULLY ORGANIC RETINAL PROSTHESIS REINSTATES VISION IN BLIND ANIMALS
1 Italian Institute of Technology, Synaptic Neuroscience and Technologies, Genova, Italy
Abstract text :
The degeneration of photoreceptors in the retina is one of the major causes of adult blindness in humans. Unfortunately, no effective clinical treatments exist for the majority of retinal degenerative disorders. We report the fabrication and functional validation of a fully organic prosthesis made of P3HT as a photosensitive semiconductive layer, PEDOT:PSS as a conductive layer and silk fibroin as a biocompatible passive substrate for long-term in vivo subretinal implantation in the eye of Royal College of Surgeons rats, a widely recognized model of Retinitis pigmentosa. Electrophysiological and behavioral analyses revealed a prosthesis-dependent recovery of light sensitivity and visual acuity that persisted up to 6-10 months after surgery. The rescue of the visual function was accompanied by an increase in the basal metabolic activity of the primary visual cortex, as demonstrated by PET imaging. This was complemented by a modest and transitory inflammatory response that decreased soon after surgery with full preservation of retinal morphology. In parallel, the authors are moving ahead with the functional validation of a device optimized for implantation in a swine model of degenerative blindness. The experimental findings obtained so far highlight the possibility of developing a new generation of fully organic, highly biocompatible, low cost, and functionally autonomous photovoltaic prostheses for subretinal implants to treat degenerative blindness. This line of translational research is of clinical relevance in retinal degenerative diseases, characterized by an incidence of 1 in every 4000 people worldwide, for which there is currently no medical treatment.