Correlation of vascular endothelial growth factor and CD105-microvascular density in primary pterygium

The relationship between the expression of vascular endothelial growth factor (VEGF) and microvascular density (MVD) marked by CD105 (CD105-MVD), and that between CD105-MVD and the clinicopathological characteristics of primary pterygium were investigated. The streptavidin-biotin complex (SABC) immunohistochemical staining in paraffin-embedded tissues was used to detect the expression of VEGF in 23 cases of primary pterygia and 7 normal conjunctival specimens. The antibody against CD105 was used to display vascular endothelial cells, and MVD was examined by counting the CD105-positive vascular endothelial cells. The correlations of VEGF and CD105-MVD, and those of CD105-MVD and clinicopathological data were analyzed by using SPSS 12.0. The expression of VEGF was significantly increased in epithelia (P=0.000), endothelia and stroma cells (P=0.005) in primary pterygia as compared with normal conjunctivae. The CD105-MVD in pterygia (mean 19.22±6.68) was higher than that in normal conjunctivae (mean 4.00±2.15, P=0.000). MVD in pterygia was significantly associated with the Tan classification (P=0.000) and the VEGF expression level in the stroma (P=0.020), but not with sex (P=0.61), age (P=0.150) or the VEGF expression level in the epithelia (P=0.518). Our results suggest that over-expression of VEGF and high CD105-MVD in primary pterygium may contribute to the progression by increasing angiogenesis and growth of primary pterygium.