Abstract
Purpose :
Corneal endothelial dysfunction, a leading indication for global corneal transplantation, necessitates innovative solutions due to the limited availability and handling challenges associated with traditional Descemet Membrane Endothelial Keratoplasty (DMEK) grafts. Our study evaluates Endo-TekTM, a novel engineered DMEK-like graft, as a viable alternative using in vitro cultured human corneal endothelial cells (HCECs) to replace traditional deceased donor tissue.
Methods :
We utilized a transparent, thin collagen vitrigel as a carrier for delivering cultured HCECs, forming the Endo-TekTM graft. Cell viability was assessed through Calcein-AM staining, and corneal endothelial markers were examined using immunofluorescence staining. In a feline model with damaged native endothelium, grafts were transplanted to assess in vivo functionality. Corneal clarity was monitored, and thickness was assessed via pachymetry over a 12-week post-surgery period. OCT, in vivo confocal microscopy, and histological analysis were performed at week 12.
Results :
The collagen-based engineered vitrigel demonstrated high transparency. Cell viability after 14 days of storage and long-distance shipping exceeded 90%. Endo-TekTM exhibited superior graft handling properties facilitating easier placement. Its high biocompatibility supported a cell density of >3,000 cell/sqmm with typical corneal endothelial cell morphology and immunofluorescence cell markers. By week 6 post-op, eyes transplanted with our grafts showed corneal clearing. Pachymetry examination revealed a significant reduction in corneal thickness compared to week 1 post-op, approaching baseline levels. In vivo confocal microscopy showed a confluent monolayer of polygonal HCECs on the graft. OCT and histological results confirmed firm graft attachment to the stroma with the presence of human cells and graft thickness <25µm.
Conclusions :
Our novel engineered EK graft offers the potential for improved material properties and cell densities for delivering in vitro cultured HCECs for transplantation. Endo-TekTM grafts maintain viability after long-distance shipping. Eyes transplanted with these grafts exhibited thinner and clearer corneas than controls, indicating restoration of corneal function. This cell-based therapy for corneal endothelial dysfunction presents a promising alternative to traditional EK using deceased donor tissues.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.