To investigate the effect of dehydration on human donor corneal stroma for biobanking.
Epithelium and endothelium of research-grade human donor corneas (n = 12) were scraped off, leaving a bare stroma with attached sclera. The tissues were placed in a large Petri dish prefilled with silica gel in the periphery and stored at room temperature for 14 days. At the end of preservation, the tissues were rehydrated by being submerged in phosphate-buffered saline for 15 minutes. Transparency (using a custom-built device) and thickness (using optical coherence tomography) measurements were recorded before dehydration, after dehydration, and after rehydration of the tissues. Periodic acid-Schiff and alpha-smooth muscle actin (α-SMA) staining before dehydration and after rehydration were performed to determine the presence of keratocytes and expression of α-SMA. Tensile stress-strain before dehydration and after rehydration was performed to evaluate the biomechanical properties.
No difference in corneal transparency before dehydration (69.57 ± 6.41%) and after rehydration (67.37 ± 2.82%), P = 0.36, was observed. The corneas were more compact after dehydration. A significant change in thickness between before dehydration (625.8 ± 75.58 μm) and after rehydration (563.6 ± 15.77 μm) stage, P = 0.03, was noticed. The thickness was reduced to 147.6 ± 3.71 μm when dehydrated. Periodic acid-Schiff staining showed presence of stromal keratocytes and α-SMA protein expressed in control, dehydrated, and rehydrated corneas. There was no significant difference in the stiffness between control (27.86 ± 11.65 MPa) and rehydrated corneas (31.46 ± 11.41 MPa).
Human donor corneal stroma can be biobanked for up to 2 weeks in a dehydrated condition without losing their molecular or biomechanical properties after rehydration.
*St Paul's Eye Unit, Department of Corneal and External Eye Diseases, Royal Liverpool University Hospital, Liverpool, United Kingdom;
†Department of Eye and Vision Science, University of Liverpool, Liverpool, United Kingdom;
‡Instituto Universitario Fernandez-Vega, Universidad de Oviedo and Fundacion de Investigacion on Oftalmologica, Oviedo, Spain;
§International Center for Ocular Physiopathology, The Veneto Eye Bank Foundation, Venice, Italy; and
¶Institute of Ophthalmology, University College London, London, United Kingdom.
Correspondence: Vito Romano, MD, St Paul's Eye Unit, Department of Corneal and External Eye Diseases, Royal Liverpool University Hospital, Liverpool, United Kingdom L7 8XP (e-mail: email@example.com).
Supported by the 2016 Fight for Sight—Small Grant Award Scheme to V. Romano and 2017 Eye Bank Association of America (EBAA) Richard Lindstrom Research Grant to M. Parekh.
V. Romano and M. Parekh contributed equally to this study.
Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (www.corneajrnl.com).
Received June 11, 2018
Received in revised form December 04, 2018
Accepted December 10, 2018