Scientists Discover Why Cornea Is Transparent And Free Of Blood Vessels, Allowing Vision:
The key, say the researchers, is the unexpected presence of large amounts of the protein VEGFR-3 (vascular endothelial growth factor receptor-3) on the top epithelial layer of normal healthy corneas.
According to their findings, VEGFR-3 halts angiogenesis (blood vessel growth) by acting as a "sink" to bind or neutralize the growth factors sent by the body to stimulate the growth of blood vessels.
Nice, except that "Why" is an evolutionary question: they should have used "How" throughout the press release.
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