Efficacy of rhNGF-loaded amniotic membrane transplantation for rabbit corneal epithelial and nerve regeneration
Authors:   Medical College of Qingdao University, Qingdao 266000, Shandong Province, China, Wan Lu-Qin , Wang Hui-Feng ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Chen Chen ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Li Hua ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Zhang Yuan ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Xue Jun-Fa ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Zhou Qing-Jun ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China, Xie Li-Xin ,   State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University &amp; Shandong Academy of Medical Sciences, Qingdao 266071, Shandong Province, China
Published: October 2021

AIM: To evaluate the efficacy of recombinant human nerve growth factor-loaded amniotic membrane (rhNGF-AM) on corneal epithelial and nerve regeneration in rabbit model.
METHODS: Freshly prepared human amniotic membrane (AM) were immersed into PBS buffer containing 100 or 500 μg/mL rhNGF for 15, 30, and 60min at 4℃. The in vitro release kinetics of rhNGF was measured with ELISA. For in vivo evaluation, the AM were immersed with 500 μg/mL rhNGF for 30min. Fifty-seven rabbits were selected to establish corneal epithelial defect model. In addition to the 19 rabbits in control group, 38 rabbits received AM transplantation with or without rhNGF after the removal of central epithelium. Corneal epithelial defect area, sub-epithelial nerve fiber density, corneal sensitivity, rhNGF contents in resident AM and corneas were measured after the surgery.
RESULTS: rhNGF was sustained release from the AM within 14d in vitro, with the positive correlation with initial immersion concentration. The immersion of AM in 500 μg/mL rhNGF for 30min achieved the most stable release within 14d. After transplantation in rabbit cornea, a high concentration of rhNGF in resident rhNGF-AM and cornea was maintained within 8d. Corneal epithelial healing, nerve fiber regeneration and the recovery of corneal sensitivity were significantly accelerated after the rhNGF-AM transplantation when compared to simple AM transplantation (all P<0.05).
CONCLUSION: Simple immersion of AM achieves the sustained release of rhNGF, and promotes corneal epithelial wound healing and nerve regeneration, as well as the recovery of corneal sensitivity in rabbit.