OptiDicer reduces CUG RNA accumulation in corneal endothelial cells affected by Fuchs’ dystrophy

(In-Person) Poster Presentation 

Fuchs’ endothelial corneal dystrophy (FECD) is a genetic disease which leads to eye pain, significant loss of vision and corneal lesions called guttae.

Late-onset FECD is characterized by the expanded repeat trinucleotide sequence (CTG)n (n>30- 40) in the TCF4 gene. The accumulation of CUG RNA in the nucleus forms cytotoxic RNA foci. Recently, we developed a recombinant variant of DICER, OptiDicer, which can degrade double-strand RNA through RNaseIII activity. In this study, we examined whether OptiDicer can decrease CUG RNA accumulation in corneal endothelial cells from patients with Fuchs dystrophy.

F35T cells, Human corneal endothelial cells from an FECD patient with (CTG)n n>1000, were used in this study. The cells were transfected with OptiDicer and a control, and then subjected to in situ hybridization in order to detect CUG RNA accumulation. The images were obtained with an EVOS fluorescence microscope, and the number of CUG RNA accumulation was counted. The average number of CUG RNA accumulation was 1.9+/-1.4 in OptiDicer-F35T and 2.9+/-1.7 in D2A-OptiDicer control F35T (p<0.001), respectively.

We found that OptiDicer significantly decreased CUG-RNA accumulation in late-onset FECD patient derived corneal endothelial cells, although the low transfection efficiency may underestimate OptiDicer effect. Our result suggests OptiDicer can be a potential treatment for long CUG RNA repeat derived FECD. Future studies will explore OptiDicer in other cell lines from FECD.