Effect of TLR2 monoclonal antibody on new blood vessels and immune rejection response after keratoplasty

Wang Ji,Wen Feng,Yuan Jianshu

doi:10.4314/tjpr.v18i1.3

Abstract

Purpose : To investigate the effect of TLR2 (toll-like receptor 2) monoclonal antibody on formation of new blood vessels and immune rejection response after keratoplasty. Methods : The rats were randomly divided into negative control group consisting of 16 rats from allogeneic corneal transplantation, and TLR2 monoclonal antibody group (study group) made up of 16 rats from allogeneic corneal transplantation treated with TLR2 monoclonal antibody. A group of 8 rats served as normal control. The study group was treated with 0.5 g·L-1 TLR2 monoclonal antibody through sub-conjunctival injection once daily for 5 days, while the normal control and negative control groups were given an equivalent volume of normal saline in place of TLR2. Corneal transparency and neovascularization were observed under slit lamp daily after operation, and scored using rejection index. Results : In the TLR2 monoclonal antibody group, the corneal structure was still clear, and only a few inflammatory cells infiltrated the stromal layer. There were trace amounts of TLR2 expression in the corneal epithelium of rats in normal control group, negative control group and TLR2 monoclonal antibody group. In the negative control group, the expression of TLR2 in the corneal epithelium and stromal cells significantly increased, especially in the stromal layer. Conclusion : TLR2 monoclonal antibody exerts a significant effect on neovascularization and immune rejection after corneal transplantation in rats. Thus, it may be clinically suitable for the prevention and treatment of rejection arising from corneal transplantation. Keywords : TLR2 monoclonal antibody, Corneal transplantation, Neovascularization, Immune rejection

Highlights

Keratopathy is the second leading cause of blindness after cataracts [1]
Corneal edema was observed in 5 cases of allograft corneal transplantation at 1 - 4 days after operation
In the Toll-like receptor 2 (TLR2) monoclonal antibody group, corneal new vessels grew into the grafts, which were transparent and the pupils were visible

Summary

INTRODUCTION

Keratopathy is the second leading cause of blindness after cataracts [1]. A significant number of keratopathy patients can be cured only through corneal transplantation. As the number of corneal transplant patients increases yearly, the cumulative graft rejection cannot be ignored [4]. It is the most widely expressed molecule in the cloned human TLR family, which recognizes most pathogenic microorganisms In previous experiments, it was confirmed at the gene, molecular and cellular levels that the expression of TLR2 mRNA was significantly increased and transferred to the cell membrane on the 9th day after corneal allograft transplantation in rats [7]. The effect of TLR2 monoclonal antibody on neovascularization and immune rejection after corneal transplantation was investigated. A rat model of allogeneic penetrating corneal transplantation was established according to a previous report [7]. 0.1 mL of Tarivid® eye drop was applied to the conjunctival sac three times /day (morning, afternoon and evening). A brownish color in the cytoplasm or nucleus was considered as evidence of positively-stained cells

RESULTS

DISCUSSION

CONCLUSION

Conflict of Interest