Gelatin methacryloyl hydrogel eye pad loaded with amniotic extract prevents symblepharon in rabbit eyes.

OBJECTIVE: The aim was to evaluate the ability of gelatin methacryloyl (GelMA) hydrogel eye pads loaded with amniotic extract to prevent symblepharon in rabbits. MATERIALS AND METHODS: Forty-eight rabbits were divided into 3 groups. After ocular alkali burn, Group A (n=16) was treated with amniotic extract-loaded hydrogel eye pads placed in the conjunctival sac, Group B (n=16) was treated with amniotic membrane transplantation, and Group C (n=16) received no treatment. At 1, 2, 3, and 4 weeks post-injury, 4 rabbits from each group were selected to evaluate for symblepharon, determine epithelial healing rate and corneal neovascularization, conduct histopathology, and to quantify the expression of TGF-β1. RESULTS: At 1 week post-injury, the epithelial healing rate in Groups A and B was higher than Group C (p=0.002, 0.001, respectively). At 2 weeks, corneal neovascularization in Group B was less than Group C (p=0.004). At 3 and 4 weeks, no symblepharon has been found in Group A, but it was found in some eyes in Group B and C (p=0.009, 0.013). Further, the expression of TGF-β1 in Group A was lower than in Group B and C (p<0.001). H&E staining showed that the controls in Group C had more edema and inflammatory cell infiltration in the first 2 weeks, relative to Groups A and B. At 4 weeks, Masson’s Trichrome staining showed that fibers were most regularly aligned in Group A and that immuno- histochemical staining found that proliferating cell nuclear antigen was highest expressed in Group C. CONCLUSIONS: Treatment with GelMA hydrogel eye pads loaded with amniotic extract shortly after chemical injury prevented symblepharon in rabbits. [ABSTRACT FROM AUTHOR]