Effects of Amnion Membrane Transplantation and Cross-linking Treatment
in a Rabbit Model of Corneal Alkali Burn

Authors: Sevgi ÖZEL SUBAŞI (1), Melda YARDIMOGLU (2), Yusufhan YAZIR (3), Selenay FURAT
RENÇBER (2), Kübra KAVRAM (4), Özgül ALTINTAŞ (1), Süleyman KARAMAN (1)
1. Department of Ophthalmology, Faculty of Medicine, Kocaeli University, Kocaeli, TURKEY
2. Department of Histology and Embryology, Faculty of Medicine, Kocaeli University, Kocaeli, TURKEY
3. Department of Histology and Embryology; Center of Stem Cell and Gene Therapies Research and Practice,
Faculty of Medicine, Kocaeli University, Kocaeli, TURKEY
4. Department of Histology and Embryology, The Institute of Health Sciences, Kocaeli University , Kocaeli,
TURKEY
DOI: 10.1002/EMC2016.0004
Corresponding email: melda.yardimoglu@gmail.com
Keywords: alkali burn, cross-linking treatment, amnion transplantation

Eye burn is widely seen and may be caused by various chemical and physical agents including acids, alkalis, fire, etc. They are most commonly a consequence of chemical handling accidents and may result in permanent damage to the ocular surface and visual function(1-4). We aimed to evaluate the effect of amnion transplantation and collagen crosslinking treatments after alkali burn in rabbit corneas. 32 New Zealand white rabbits were divided into five groups as control (group 1? n=5), alkali burned (group 2?
n=8), amnion transplantation treatment (group 3? n=8), crosslinking treatment (group 4? n=8), and combined treatment (group 5? n=8). Alkali injury was induced only in the right corneas of rabbits using 1N NaOH except the control group. After the alkali burn, group 3 was applied amnion transplantation, group 4 was applied collagen crosslinking, and group 5 received combined treatment. All groups were performed medical treatment
during 21 days. Histomorphology was evaulated with H&E and Masson trichrome stained sections (5). The apoptosis was assessed in the corneal epithelium and stroma using TUNEL assay. CD68 immunostaining was applied for evaluation of inflamation.
In group 1, the corneas of healthy rabbits had normal appearance in terms of epithelium, stroma, and endothelium. There was severe acute corneal inflammation characterized with polymorphonuclear leukocyte infiltration, increased degenerative cells, stromal oedema, hemorrhage, keratocyte loss and disorganised collagen fiber pattern in group 2. The epithelial regeneration was better in the group 4 than the group 2 (p=0.010) but no significant difference was observed in terms of stromal oedema and hemorrhage. In group 4, the corneal epithelial splitting, inflammatory cell infiltration and stromal damage less than the other treatment groups but no significant difference was observed. There was a significant decrease in the mean number of TUNEL(+) cells in the corneal epithelium and stroma in group 4 compared to group 2 (p=0.044). There was a
significant decrease in CD68(+) cell number in group 4 (p= 0.001) and group 5 (p=0.039) compared to group 2 (Fig.2). Collagen crosslinking treatment can improve the corneal reepithelization after alkali burn and reduce the destruction of corneal collagen fibers, apoptosis and infiltration of inflammatory cells in cornea. Although further clinical trials are required, the findings presented herein suggest a using of crosslinking treatment for alkali burn.
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