Advancing in vivo modelling and delivery systems for triplet repeat expansion‐mediated corneal endothelial dystrophy: Implications in Anti‐miR therapy

Abstract

Aims/Purpose: Triplet repeat expansion‐mediated endothelial corneal dystrophy, including Fuchs endothelial corneal dystrophy (FECD), is characterized by abnormal expansions of trinucleotide repeats, resulting in corneal endothelium dysfunction [1,2]. This study aims to characterize a reliable in vivo model, that it lacks, and explore the therapeutic potential of anti‐miRs, which have shown efficacy in other disorders involving triplet repeat expansions [3,4,5]. Current invasive delivery methods for eye‐based treatments present challenges, so our focus is on optimizing non‐invasive delivery methods for anti‐miR‐based therapy.Methods: A transgenic mouse model with a significant CTG repeat expansion (>1000), established in DM1, was investigated as an in vivo model for corneal endothelial dystrophy. The Fuchs‐like phenotype of the disease was characterized using immunohistochemistry and FISH techniques. Delivery methods were explored to enhance the targeting of corneal endothelial cells (CEC). Delivery efficacy and marker expression were assessed using fluorescence, RT‐qPCR, PCR, western blotting, and immunocytochemistry techniques. FECD cell cultures were established to evaluate the challenging FECD‐specific delivery systems.Results: A novel in vivo model has been characterized for studying corneal endothelial dystrophy caused by triplet repeat expansion, exhibiting similarities to the Fuchs‐like phenotype. Enhanced delivery methods have been identified to improve transfection efficiency in endothelial (HUVEC) and CEC. Successful establishment of FECD cell cultures has allowed the evaluation of these enhanced delivery systems.Conclusions: The first successful characterization of an in vivo model for triplet repeat expansion‐mediated corneal endothelial dystrophy has been achieved. This model shows potential for assessing the reversal of these phenotypes in the ocular region. Moreover, the successful delivery of new systems across CEC suggests the possibility of non‐invasive administration of anti‐miR directly into the eye. This breakthrough opens the door for future research on anti‐miRs in other diseases caused by triplet repeat expansion, such as FECD.ReferenceIn PMID: [1] 28886202, [2] 34130750, [3] 29946070, [4] 32805487, [5] 22764244.