title: Characterization of a Polymer-Based, Fully Organic Prosthesis for Implantation into the Subretinal Space of the Rat.
abstract: Replacement strategies arise as promising approaches in case of inherited retinal dystrophies leading to blindness. A fully organic retinal prosthesis made of conjugated polymers layered onto a silk fibroin substrate is engineered. First, the biophysical and surface properties are characterized; then, the long-term biocompatibility is assessed after implantation of the organic device in the subretinal space of 3-months-old rats for a period of five months. The results indicate a good stability of the subretinal implants over time, with preservation of the physical properties of the polymeric layer and a tight contact with the outer retina. Immunoinflammatory markers detect only a modest tissue reaction to the surgical insult and the foreign body that peaks shortly after surgery and progressively decreases with time to normal levels at five months after implantation. Importantly, the integrity of the polymeric layer in direct contact with the retinal tissue is preserved after five months of implantation. The recovery of the foreign-body tissue reaction is also associated with a normal b-wave in the electroretinographic response. The results demonstrate that the device implanted in nondystrophic eyes is well tolerated, highly biocompatible, and suitable as retinal prosthesis in case of photoreceptor degeneration.
authors.affiliation: Center for Nano Science and Technology, Fondazione Istituto Italiano di Tecnologia, Via G. Pascoli 70/3, 20133, Milano, Italy.
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Antognazza
authors.affiliation: Department of Biotechnology and Applied Clinical Science, University of L'Aquila, Via Vetoio, Coppito 2, 67100, L'Aquila, Italy.
authors.forename: Mattia
authors.initials: M
authors.lastname: Di Paolo
authors.affiliation: Center for Synaptic Neuroscience and Technology, Fondazione Istituto Italiano di Tecnologia, Largo Giovanna Benzi 10, 16132, Genova, Italy.
authors.forename: Diego
authors.initials: D
authors.lastname: Ghezzi
authors.affiliation: Unità Operativa di Oculistica, Ospedale Sacro Cuore - Don Calabria, Via don A. Sempreboni 5, 37024, Negrar (Verona), Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Mete
authors.affiliation: Department of Biotechnology and Applied Clinical Science, University of L'Aquila, Via Vetoio, Coppito 2, 67100, L'Aquila, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Di Marco
authors.affiliation: Center for Synaptic Neuroscience and Technology, Fondazione Istituto Italiano di Tecnologia, Largo Giovanna Benzi 10, 16132, Genova, Italy.
authors.forename: José Fernando
authors.initials: JF
authors.lastname: Maya-Vetencourt
authors.affiliation: Department of Biotechnology and Applied Clinical Science, University of L'Aquila, Via Vetoio, Coppito 2, 67100, L'Aquila, Italy.
authors.forename: Rita
authors.initials: R
authors.lastname: Maccarone
authors.affiliation: Center for Nano Science and Technology, Fondazione Istituto Italiano di Tecnologia, Via G. Pascoli 70/3, 20133, Milano, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Desii
authors.affiliation: Center for Nano Science and Technology, Fondazione Istituto Italiano di Tecnologia, Via G. Pascoli 70/3, 20133, Milano, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Di Fonzo
authors.affiliation: Center for Synaptic Neuroscience and Technology, Fondazione Istituto Italiano di Tecnologia, Largo Giovanna Benzi 10, 16132, Genova, Italy.
authors.forename: Mattia
authors.initials: M
authors.lastname: Bramini
authors.affiliation: Unità Operativa di Oculistica, Ospedale Sacro Cuore - Don Calabria, Via don A. Sempreboni 5, 37024, Negrar (Verona), Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Russo
authors.affiliation: Center for Nano Science and Technology, Fondazione Istituto Italiano di Tecnologia, Via G. Pascoli 70/3, 20133, Milano, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Laudato
authors.affiliation: Innovhub-SSI, Silk Division, Via Giuseppe Colombo 83, 20133, Milano, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Donelli
authors.affiliation: Animal Facility, IRCCS Azienda Ospedaliera Universitaria San Martino IST Istituto Nazionale per la Ricerca sul Cancro, Largo Giovanna Benzi 10, 16132, Genova, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Cilli
authors.affiliation: Innovhub-SSI, Silk Division, Via Giuseppe Colombo 83, 20133, Milano, Italy.
authors.forename: Giuliano
authors.initials: G
authors.lastname: Freddi
authors.affiliation: Unità Operativa di Oculistica, Ospedale Sacro Cuore - Don Calabria, Via don A. Sempreboni 5, 37024, Negrar (Verona), Italy.
authors.forename: Grazia
authors.initials: G
authors.lastname: Pertile
authors.affiliation: Center for Nano Science and Technology, Fondazione Istituto Italiano di Tecnologia, Via G. Pascoli 70/3, 20133, Milano, Italy.
authors.forename: Guglielmo
authors.initials: G
authors.lastname: Lanzani
authors.affiliation: Department of Biotechnology and Applied Clinical Science, University of L'Aquila, Via Vetoio, Coppito 2, 67100, L'Aquila, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Bisti
authors.affiliation: Center for Synaptic Neuroscience and Technology, Fondazione Istituto Italiano di Tecnologia, Largo Giovanna Benzi 10, 16132, Genova, Italy. fabio.benfenati@iit.it.
authors.forename: Fabio
authors.initials: F
authors.lastname: Benfenati
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D020007:Implants, Experimental; D008422:Materials Testing; D051381:Rats; D012160:Retina
chemical_list: D001672:Biocompatible Materials
keywords: RCS rats; biocompatibility; conjugated polymers; retinal prosthesis; silk fibroin