Increased Corneal Endothelial Cell Migration in Fuchs Endothelial Corneal Dystrophy: A Live Cell Imaging Study.

ABSTRACT

Purpose: To investigate if corneal endothelial cells (CECs) in Fuchs endothelial corneal dystrophy (FECD) have altered cellular migration compared with normal controls. Design: Comparative analysis. Materials Descemet's membrane and CECs derived from patients with FECD undergoing endothelial keratoplasty or normal cadaveric donors. Methods: Ex vivo specimens were used for live cell imaging and generation of immortalized cell lines. Live imaging was performed on FECD and normal CECs and on ex vivo specimens transfected with green fluorescent protein. Migration speeds were determined as a function of cellular density using automated cell tracking. Ex vivo specimens were classified as either FECD or normal low cell density (nonconfluent) or high cell density (confluent). Scratch assay was performed on CECs seeded at high confluence to determine migration speed. Genetic analysis from blood samples or CECs was performed to detect a CTG repeat expansion in the TCF4 gene. Main Outcome Measures: Mean cell migration speed. Results: Fuchs endothelial corneal dystrophy CECs in low cell density areas displayed increased mean speed (0.391 ± 0.005 µm/minute vs. 0.364 ± 0.005 µm/minute; P < 0.001) and mean maximum speed (0.961 ± 0.010 µm/minute vs. 0.787 ± 0.011 µm/minute; P < 0.001) compared with normal CECs, and increased mean maximum speed (0.778 ± 0.014 µm/minute vs. 0.680 ± 0.011 µm/minute; P < 0.001) in high cell density areas ex vivo. Similarly, FECD CECs displayed increased mean speed compared with normal CECs (1.958 ± 0.020 µm/minute vs. 2.227 ± 0.021 µm/minute vs. 1.567 ± 0.019 µm/minute; P < 0.001) under nonconfluent conditions in vitro. Moreover, FECD CECs also displayed increased mean speed compared with normal CECs under high confluent conditions as detected by scratch assay (37.2 ± 1.1% vs. 44.3 ± 4.1% vs. 70.7 ± 5.2%; P < 0.001). Morphologic analysis showed that FECD CECs displayed an increased fibroblastic phenotype as detected by filamentous-actin labeling. Conclusions: Fuchs endothelial corneal dystrophy CECs demonstrated increased migration speed compared with normal CECs. Further investigation into the mechanisms of heightened cell migration in FECD is needed and may provide insight into its pathogenesis, as well as having implications on descemetorhexis without endothelial keratoplasty.