Abstract:  Objective To compare the expression of Toll-like receptors (TLR2, TLR3, TLR4) and vascular endothelial growth factor (VEGF) in primary and recurrent pterygium. Design Experimental study. Participants 36 cases of primary pterygium tissue, 24 cases of recurrent pterygium tissue and 20 cases of normal conjunctiva tissue. Methods TLR2, TLR3, TLR4, VEGF and tumor necrosis factor (TNF)-α were detected with immunohistochemistry among normal conjunctiva, primary and recurrent pterygium. The correlation between VEGF and the expression of TLR2, TLR3 and TLR4 was analyzed. Main Outcome Measures The expression amount, positive expression rate of TLR2, TLR3, TLR4, VEGF and TNF-α; correlation coefficient. Results The expressions of TLR2, TLR3 and TLR4 in normal conjunctiva group were weaker, in two pterygium groups were stronger, and in recurrent pterygium was strongest. A large number of brown yellow particles of VEGF were distributed in the stromal layer of recurrent pterygium, and also expressed in the epithelial layer. VEGF was positively correlated with the expression of TLR2, TLR3 and TLR4 in recurrent pterygium (r=0.512, P=0.001; r=0.671, P=0.001; r=0.482, P=0.001). Conclusion The expression of TLR2, TLR3, TLR4 and VEGF in recurrent pterygium was higher than that in primary pterygium, suggesting that immune inflammation and VEGF may be important factors in the mechanism of pterygium recurrence. Autoimmune inflammatory pathway is involved in the recurrence of pterygium by regulating angiogenesis. （Ophthalmol CHN, 2022, 31: 156-161）

Key words:  Toll-like receptor, vascular endothelial growth factor, pterygium