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Cursiefen, C. et al. Nonvascular VEGF receptor 3 expression by corneal epithelium maintains avascularity and vision. Proc. Natl. Acad. Sci. USA 103 , 11405-11410

Schepens Eye Research Institute, Harvard Medical School, 20 Staniford Street, Boston, MA 02114, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 08/2006; 103(30):11405-10. DOI: 10.1073/pnas.0506112103
Source: PubMed

ABSTRACT

Transparency of the cornea, the window of the eye, is a prerequisite for vision. Angiogenesis into the normally avascular cornea is incompatible with good vision and, therefore, the cornea is one of the few tissues in the human body where avascularity is actively maintained. Here, we provide evidence for a critical mechanism contributing to corneal avascularity. VEGF receptor 3, normally present on lymphatic and proliferating blood vascular endothelium, is strongly constitutively expressed by corneal epithelium and is mechanistically responsible for suppressing inflammatory corneal angiogenesis.

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    • "The corneal epithelium constitutively expresses VEGFR-3, which binds to angiogenic VEGF-C and VEGF-D. As a result, it inhibits both hemangiogenesis and lymphangiogenesis, thereby contributing to the regulation of ocular surface immunity (Cursiefen et al., 2006). Another important anti-angiogenic factor constitutively expressed by cornea is thrombospondin (TSP)-1 (Hiscott et al., 1997), which helps to suppress inflammation-induced corneal angiogenesis (Cursiefen et al., 2004; Cursiefen et al., 2011). "
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