Ultrastructural features of the corneal epithelium with micromolecular compound J2 in the corneal allograft of rats using atomic force microscopy

Abstract

Objective: To study the ultrastructural features of the corneal epithelium in the corneal allograft of rats with micromolecular compound J2. Methods: An experimental study. Primarily cultured corneal epithelial cells of rats were used. Mononuclear cells (MNCs) by density gradient centrifugation were assigned into the experimental group [MNCs (2 ml)+corneal epithelial cells+J2], control group [MNCs (2 ml)+corneal epithelial cells] and blank group (corneal epithelial cells). Quantity of CD80 expression was obtained by flow cytometry after coculture. Amplitude and height images were obtained by tapping mode atomic force microscopy (AFM) with a scan rate of 2 Hz and an integral gain of 0.3 to 0.5. Statistical analysis of Ra, Rq, Rvm and Rt was performed using the single-factor analysis of variance, and P value was calculated. Results: There were obvious differences in the ultrastructure measured by AFM among groups. Ra was 86.75±12.60 in the experimental group, 120.23±12.11 in the control group, and 61.94±10.62 in the blank group (F=306.92, P<0.01). Rq was 102.53±9.45, 138.30±10.13, and 91.96±7.25, respectively, in the three groups (F=361.85, P<0.01). Rvm was -42.21±14.22, -67.36±10.89, and -32.18±19.01, respectively (F=72.22, P<0.01). Rt was 437.32±15.66, 495.32±13.96, and 339.92±11.22, respectively (F=1634.26, P<0.01). The one way analysis of variance showed significant differences in these parameters among groups. Conclusions: Corneal epithelial cells of rats activated by MNCs had higher CD80 expression, but the expression became decreased with micromolecular compound J2. The ultrastructure of the corneal epithelium became coarser after MNCs activation, and the number of protrusions increased significantly. The ultrastructural changes were alleviated by J2.(Chin J Ophthalmol, 2021, 57: 608-613).