Retina is one of the well-developed structures of eyes with several layers of neurons, which are interconnected by synapses. Degenerative retinal diseases such as retinitis pigmentosa and age-related macular affects millions of people, and without any treatment, these diseases lead to an irreversible blindness. In order to treat degenerative retinal diseases, extensive research has been conducted and various treatment approaches have been proposed, such as drug therapy, gene therapy, cell therapy, artificial retinas, and tissue engineering.
In retinal tissue engineering, retinal implant restores useful vision for limited visual abilities by stimulating the surviving retinal nerve cells. It is also advantageous in increasing cell survival and directing stem cells or progenitor cell differentiate toward a photoreceptor state. In retinal tissue engineering, biocompatibility, non-toxicity, ability to excrete proper signals and compatible physical characteristics are essential features of the treatment method.
Recent advances in fabrication of polymers such as polyglycolic acid (PGA), polylactic acid (PLLA), poly-DL-lactic acid (PDLLA), hyaluronic acid (HA), polycaprolactone (PCL), and chitosan (CS) led to development of polymeric scaffolds which are implanted in retina area; however, absence of proper signaling in these polymeric scaffolds wouldn't result in an expected improvement in regeneration of retina.
Different signals like chemical, mechanical and electrical signals can affect cellular behavior in a tissue regeneration process. Electromagnetic waves, for example light, are the most effective signals for retinal cells. Therefore, there is a need in the art to provide tissue engineering scaffolds with better mechanical and optical properties to improve cell growth and cell differentiation, particularly in retina. Also, there is a need for a polymeric scaffold with the ability of producing proper electromagnetic signals for improving retina regeneration.