Karl D. Brown, Jean-Pierre Scheerlinck, Penelope McKelvie, Hong Zhang, Greg Qiao, Mark Daniell
Purpose: To culture of corneal endothelial cells on a synthetic ftlm suitable for implantation then provide in vivo proof of principle for tissue-engineered Descemet?s stripping endothelial keratoplasty (TE-DSEK).
Methods: Ovine corneal endothelial cell (CEC) monolayers were cultured to con?uence directly on an novel ultra-thin (50 ?m) poly(ethylene glycol)- based hydrogel ftlm (PHF). Immuno?uorescence was used to detect ZO-1. A sheep model of corneal endothelial dystrophy was created by surgical removal of CEC from a 7 mm diameter area of the central cornea. The TE-DSEK procedure was essen- tially the same as Descemet?s stripping automated endothelial keratoplasty (DSAEK). Negative control animals received a PHF without CEC, or an implant not placed over the endothelial wound. Animals were observed for at least 21 days post surgery and scored for in?amation, corneal clarity, and oedema on a validated pro-forma. Oedema was rated 0 ? 4, with 0 being no oedema and 4 being maximally thick. Post mortem whole eyes were subjected to haemotoxylin-eosin histology.
Results: Cultured cells were positive forZO-1. No evidence of toxicity or immunogenicity was observed in both clinical observations and histologi- cal sections. The PHF was completely degraded before day 21. Allogeneic TCE was non-toxic and non-immunogeneic for >20 days (n = 13). In ani- mals receiving TCE the PHF completely degraded in
<21 days. In test animals the TCE abated oedema (ftnal score 0 or 1, 70% n = 10). Conclusion: An implant consisting of CEC cultured on a PHF may be able to replace donor tissue for endothelial keratoplasty.