A novel therapeutic approach to corneal alkaline burn model by targeting fidgetin-like 2, a microtubule regulator

Purpose: The purpose of this study was to determine the efficacy of nanoparticle-encapsulated Fidgetin-like 2 (FL2) siRNA (FL2-NPsi), a novel therapeutic agent targeting the FL2 gene, for the treatment of corneal alkaline chemical injury. Methods: Eighty 12-week-old, male Sprague-Dawley rats were divided evenly into 8 treatment groups: prednisolone, empty nanoparticles, control-NPsi (1 μM, 10 μM, and 20 μM) and FL2-NPsi (1 μM, 10 μM, and 20 μM). An alkaline burn was induced onto the cornea of each rat, which was then treated for 14 days according to group assign-ment. Clinical, histopathologic, and immunohistochemical analyses were conducted to assess for wound healing. FL2-NPsi-mediated knockdown of FL2 was confirmed by in vitro quantitative polymerase chain reaction (qPCR). Toxicity assays were performed to assess for apoptosis (terminal deoxynucleotidyl transferase-mediated deoxyuri-dine triphosphate nick-end labeling [TUNEL] assay) and nerve damage (whole mount immunochemical staining). Statistical analyses were performed using Student’s t-test and ANOVA. Results: Compared with controls, FL2-NPsi-treated groups demonstrated enhanced corneal wound healing, with the 10 and 20 μM FL2-NPsi-treated groups demonstrating maximum rates of corneal re-epithelialization as assessed by ImageJ software, enhanced corneal transparency, and improved stromal organization on histology. Immunohisto-chemical analysis of vascular endothelial cells, macrophages, and neutrophils did not show significant differences between treatment groups. FL2-NPsi was not found to be toxic to nerves or induce apoptosis (p = 0.917). Conclusions: Dose-response studies found both 10 and 20 μM FL2-NPsi to be effica-cious in this rat model. FL2-NPsi may offer a novel treatment for corneal alkaline chemical injuries. Translational Relevance: Basic cell biology findings about the microtubule cytoskele-ton were used to design a therapeutic to enhance corneal cell migration, highlighting the promise of targeting microtubules to regulate corneal wound healing.