VEGF 165b is an anti-angiogenic form of VEGF 165 produced by alternative splicing. The localization of pro-angiogenic VEGF 165 and anti-angiogenic VEGF 165b was investigated during development of the vasculatures in fetal human eyes from 7 to 21 weeks gestation (WG). The fetal vasculature of vitreous, which includes tunica vasculosa lentis (TVL), had moderate VEGF 165 immunoreactivity at 7WG and very little VEGF 165b. Both forms were elevated at 12WG. VEGF 165 then decreased around 17WG when the TVL regresses but VEGF 165b remained elevated. In choroid, VEGF 165 was present in forming choriocapillaris (CC) and retinal pigment epithelium (RPE) at 7WG while VEGF165b was present in CC and mesenchymal precursors within the choroidal stroma. By 21WG, both forms were elevated in RPE and choroidal blood vessels but VEGF 165b was apical and VEGF 165 basal in RPE. Diffuse VEGF 165 immunoreactivity was prominent in 12WG innermost retina where blood vessels will form while VEGF 165b was present in most CXCR4 + progenitors in the inner neuroblastic layer and migrating angioblasts in the putative nerve fiber layer. By 21WG, VEGF 165 was present in nerve fibers and VEGF 165b in the inner Muller cell process. The localization of VEGF 165b was distinctly different from VEGF 165 both spatially and temporally and it was often associated with nucleus in progenitors.
- Endothelial cells
- Vascular endothelial growth factor
ASJC Scopus subject areas
- Developmental Biology