METHODS: From January 2018 to October 2018, surgical specimens of 60 patients with primary pterygium and 60 eyes(including 30 eyes younger than 50 years old and 30 eyes older than 50 years old)were collected from the No.474 Hospital of Chinese PLA, at the same time collect age matched strabismus diorthosis and normal conjunctiva tissues of 30 patients with retinal detachment repairs(including 15 eyes younger than 50 years, older than 50 years of age 15 eyes).The expression and localization of SDF-1/CXCR4 in pterygium tissue specimens were detected by HE staining and immunohistochemistry, and the relationship between the expression of SDF-1/CXCR4 and the clinical characteristics of patients was analyzed. The mean optical density of SDF-1 /CXCR4 was measured by IPP 6.0 software.

RESULTS: SDF-1/CXCR4 showed slightly positive or no positive expression in normal conjunctival basal cells, but positive expression in both full-layer conjunctival epithelial cells and vascular endothelial cells in pterygium, with significant difference in expression level, and more obvious expression in basal cells, showing obvious polarity. The expression levels of SDF-1 and CXCR4 in pterygium tissues were higher than those in normal conjunctival tissues, and the difference was statistically significant(P<0.05). The expression of CXCR4 in patients younger than 50 years old was greater than that in patients older than 50 years old, and the difference was statistically significant(P<0.05).

CONCLUSION: SDF-1 and CXCR4 expression is up-regulated in pterygium, suggesting that SDF-1 and CXCR4 participates in the formation of pterygium and inhibits the SDF-1/CXCR4 signaling pathway, which may inhibit the occurrence of pterygium, and may also become a drug therapeutic target for pterygium, and become a new research direction. The higher expression of CXCR4 in young pterygium patients suggests that individualized drug administration may be realized in the future to reduce the waste of medical resources.