Hydroxyapatite promotes superior adhesion and proliferation of telomerase transformed keratocytes in comparison with inert plastic skirt materials used in leading contemporary keratoprostheses

Mehta, J., Futter, C., Sandeman, S.R., Faragher, R.G.A.F., Hing, K.A., Tanner, K.E. and Allen, B.D.S. (2005) Hydroxyapatite promotes superior adhesion and proliferation of telomerase transformed keratocytes in comparison with inert plastic skirt materials used in leading contemporary keratoprostheses. British Journal of Ophthalmology, 89(10), pp. 1356-1362. (doi: 10.1136/bjo.2004.064147)

Abstract

Aim: Published clinical series suggest the osteoodontokeratoprosthesis (OOKP) may have a lower extrusion rate than current synthetic keratoprostheses. The OOKP is anchored in the eye wall by autologous tooth. The authors’ aim was to compare adhesion, proliferation, and morphology for telomerase transformed keratocytes seeded on calcium hydroxyapatite (the principal mineral constituent of tooth) and materials used in the anchoring elements of commercially available synthetic keratoprostheses. Methods: Test materials were hydroxyapatite, polytetrafluoroethylene (PTFE), polyhydroxyethyl methacrylate (HEMA), and glass (control). Cell adhesion and viability were quantified at 4 hours, 24 hours, and 1 week using a calcein-AM/EthD-1 viability/cytotoxicity assay. Focal contact expression and cytoskeletal organisation were studied at 24 hours by confocal microscopy with immunoflourescent labelling. Further studies of cell morphology were performed using light and scanning electron microscopy. Results: Live cell counts were significantly greater on hydroxyapatite surfaces at each time point (p<0.04). Dead cell counts were significantly higher for PTFE at 7 days (p<0.002). Β1 integrin expression was highest on hydroxyapatite. Adhesion structures were well expressed in flat, spread out keratocytes on both HA and glass. Keratocytes tended to be thinner and spindle shaped on PTFE. The relatively few keratocytes visible on HEMA test surfaces were rounded and poorly adherent. Conclusions: Keratocyte adhesion, spreading, and viability on hydroxyapatite test surfaces is superior to that seen on PTFE and HEMA. Improving the initial cell adhesion environment in the skirt element of keratoprostheses may enhance tissue integration and reduce device failure rates.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Tanner, Professor Kathleen
• Authors: Mehta, J., Futter, C., Sandeman, S.R., Faragher, R.G.A.F., Hing, K.A., Tanner, K.E., and Allen, B.D.S.
• Subjects: R Medicine > RE Ophthalmology
• College/School: College of Science and Engineering > School of Engineering > Biomedical Engineering
• Journal Name: British Journal of Ophthalmology
• Publisher: BMJ Publishing Group
• ISSN: 0007-1161
• Copyright Holders: Copyright © 2005 BMJ Publishing
• First Published: First published in British Journal of Ophthalmology 89(10):1356-1362
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher