May 2008
Volume 49, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2008
VEGF-A and Angiopoietins in Development of Fetal Human Ocular Vasculatures
Author Affiliations & Notes
  • G. A. Lutty
    Wilmer Eye Inst, Johns Hopkins Univ Sch of Med, Baltimore, Maryland
  • T. Hasegawa
    Wilmer Eye Inst, Johns Hopkins Univ Sch of Med, Baltimore, Maryland
  • C. Merges
    Wilmer Eye Inst, Johns Hopkins Univ Sch of Med, Baltimore, Maryland
  • D. S. McLeod
    Wilmer Eye Inst, Johns Hopkins Univ Sch of Med, Baltimore, Maryland
  • Footnotes
    Commercial Relationships  G.A. Lutty, None; T. Hasegawa, None; C. Merges, None; D.S. McLeod, None.
  • Footnotes
    Support  NIH Grants EY009357, EY016151 and EY01765
Investigative Ophthalmology & Visual Science May 2008, Vol.49, 5908. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      G. A. Lutty, T. Hasegawa, C. Merges, D. S. McLeod; VEGF-A and Angiopoietins in Development of Fetal Human Ocular Vasculatures. Invest. Ophthalmol. Vis. Sci. 2008;49(13):5908.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: : Development of the human ocular vasculatures likely requires a variety of growth factors and receptors. It was previously reported that VEGF and angiopoietin 1 requisitely collaborate during embryonic blood vessel development in mouse. Therefore, we determined the localization of angiopoietins (Ang-1 and -2) and their receptor Tie-2 and vascular endothelial cell growth factor-A (VEGF) and its type 1 and 2 receptors (R1 and R2) during the development of three human ocular vasculatures: retina, choroid, and hyaloid (HV) or fetal vasculature of vitreous.

Methods: : Alkaline phosphatase immunohistochemistry was performed for the VEGF and angiopoietin receptors and ligands and CD34 was used as a blood vessel marker on cryopreserved embryonic and fetal human eyes from 6-23 weeks gestation (WG).

Results: : The HV had immunoreactivity for VEGF and its receptors, and Ang1 and 2 and Tie-2 were present from 6-14 WG when its regression occurred. The choroid had many Ang2+ single cells at 7 WG but little immunoreactivity thereafter except in large blood vessels. Ang-1 was diffuse in all choroidal vessels at all time points. Tie-2 expression in choroidal vessels was weak at 7 WG but prominent after 12WG. VEGF was associated with choriocapillaris (CC) after 16 WG but VEGF-R2 was associated with choroidal blood vessels at all time points in development. VEGF-R1 expression increased with age in CC and large choroidal vessels. VEGF and Ang-2 expression patterns in retina were very similar throughout the time course, while Tie-2 and Ang-1 had similar patterns throughout inner retina. Apparent vascular precursors, angioblasts, in inner avascular retina were VEGF-R2 and R1 positive. When retina became vascularized at 14WG, Tie-2 and both VEGF receptors were associated with the retinal vasculature.

Conclusions: : VEGF-A and the angiopoietins are prominent in the HV and retina during vascular development. However, the three ocular vasculatures differ in expression of angiopoietins, Tie-2, VEGF and its receptors even though the CC and HV both develop by hemo-vasculogenesis. Vasculogenesis in retina involves VEGF-R2+/Tie-2- angioblasts. Almost identical localization suggests that VEGF may stimulate production of Ang-2 as demonstrated in vitro in endothelial cells (Oh et al., JBC 274:15739, 1999).

Keywords: blood supply • development • growth factors/growth factor receptors 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×