Optimization of the Manufacturing Parameters for the Assembly of Protein-Based Retinal Implants in Microgravity

LambdaVision developed a protein-based retinal implant to restore vision to the millions of people who are blinded by retinal degenerative diseases, including retinitis pigmentosa and age-related macular degeneration. Preclinical evaluation of the technology, including ex vivo extracellular recording experiments and in vivo surgical development, demonstrated that we are able to reproducibly stimulate degenerated retinal tissue and safely insert the prosthetic into the subretinal space of both rats and pigs. These milestones provide a foundation for further work to test biocompatibility and efficacy of the technology; however, the outcome of future efforts are dependent on the quality and efficiency of our manufacturing methodology. The implants are manufactured using a layer-by-layer (LBL) assembly technique, in which alternating layers of the light-activated protein, bacteriorhodopsin, and a polycation binder are sequentially deposited onto an ion-permeable film. The current terrestrial LBL approach is influenced by gravity, in which sedimentation and gradients of solutions interfere with homogeneity and uniformity of the multilayered implants. We hypothesize that manufacturing in a microgravity environment will improve the quality of the films and, as a result, will enhance stability and performance for future preclinical and clinical trials. Additionally, we predict that these improvements will reduce the cost, time, and amount of material needed for each manufacturing cycle. A pilot manufacturing trial was completed on the International Space Station (ISS) via the SpaceX CRS-16 mission, which led to the miniaturization of a LBL manufacturing device and the proof of concept of creating multilayered thin films using a Low-Earth Orbit platform. In this Phase I proposal, we will perform a series of terrestrial-based parameter setting studies to optimize the LBL manufacturing conditions prior to leveraging the ISS facilities for a subsequent Phase II flight.