Within this project the objectives were:
1. Selecting which eye disease(s) would be suitable for mRNA-based therapy
To determine which disease would suits Mercurna’s platform the most, we performed a review of the available literature for a variety of eye diseases. In our search we took also into consideration the recommendations published by the European Vision Institute. By assessing current treatment and issues for a variety of eye diseases, taking into account recent developments in novel treatments, looking for availability of cell and animal models, and assessing the potential for mRNA-based drugs, we selected a number of diseases that stood out for their suitability for Mercurna’s purpose. These diseases were investigated in more detail to determine which therapeutic proteins would be effective to inhibit mechanism(s) that are involved in the disease progression or stimulate healing of the eye tissue. We selected a list of potentially interesting therapeutic proteins, from which we selected the most promising for mRNA design and synthesis.
2. Establishing cell models of the physiological eye in healthy or diseased state to test mRNA-based drugs
Since inflammation plays in important role in the selected eye diseases, cell models were developed in which we incubated cells of the outer layer of the eye with natural components which induce inflammation alike what happens in the actual disease. We also imitated drying out of the eyes by exposing the outer side of the cells for a certain period to air, which results in an inflamed response of these cells. For all models, optimal conditions were determined and assays to detect inflammatory molecules produced by these cells were established. We could successfully demonstrate that inflammation was induced within the optimized conditions. Next to the “simplified” model of culturing an eye cell layer in 2D, we also collaborated to set-up a more advanced system in which multiple types of cells that form the cornea are cultured in 3D using experimental conditions that resemble blinking and subsequent drainage of tear fluid as it would happen under physiological circumstances. This 3D model will represent the physiological conditions as close as currently possible, and will provide us with information about Mercurna’s mRNA platform that can much better be translated to patients.
3. Selecting one or more mRNAs that could be used for therapy of the selected disease(s)
Based on the study presented under objective 1, we selected several proteins with a high therapeutic potential in the eye diseases we had chosen. Since small variations in an mRNA molecule can have a significant impact on its performance, it is important to determine which version is the most optimal. Therefore, we designed different versions of selected therapeutic mRNAs based on Mercurna’s design rules, and synthesized these mRNAs using Mercurna’s in-house facility. Therapeutic mRNAs were tested in cell models for their performance, and the mRNA version that induced the highest production of the therapeutic protein was chosen for further testing in more complex eye models.
4. Determining if Mercurna’s delivery platform can be used in its current state or should be adapted for application in eye disease
After selecting the best performing mRNAs, we determined the efficacy of these in one of our verified cell models for eye inflammation. So far, we have been able to show that the delivery of our therapeutic mRNA diminishes production of one of the factors that functions as an indicator for inflammation. Currently, we are other indicators to fully demonstrate the effect of our therapeutic mRNA. In addition, we are designing and testing improved versions of our delivery system that are optimized for application in the eye.