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.

Limbal niche cells (LNCs) in the limbal niche, a type of mesenchymal stem cells closely associated with limbal epithelial stem/progenitor cells (LESCs), heterogeneously express both mesenchymal and putative embryonic stem cell markers and play a critical role in regulating the quiescence, self-renewal, and differentiation of LESCs.Previous studies have shown that LNCs can be isolated by collagenase, dispase, dispase-collagenase and explant culture.Transwell and 3D Matrigel coculture are widely used in ex vivo studies of LNCs and LESCs, and the interactive mechanism may include SDF-1/CXCR4, Notch, BMP, Wnt, Sonic Hedgehog, and KIT/AKT signaling pathways, and various cytokines such as nerve growth factor, keratinocyte growth factor, and insulin-like growth factor.LNCs have become a hot topic in corneal epithelial tissue engineering, ocular surface reconstruction, and corneal regeneration.This review provides an overview of the research background, isolation and culture methods, interaction mechanism of LNCs with LESCs, and its application prospects.

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 CDl05-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.