Researchers uncover the secret lymphatic identity of the Schlemm's canal

Glaucoma is one of the leading causes of blindness worldwide. A major risk factor for glaucoma is elevated eye pressure due to poor drainage of aqueous humor, the fluid that provides nutrients to the eye. A specialized structure, called Schlemm's canal funnels aqueous humor from the eye back into circulation. Schlemm's canal function is critical to prevent pressure build up in the eye. In this issue of the Journal of Clinical Investigation, two research groups reveal that Schlemm's canal shares features of lymphatic vessels, which maintain interstitial fluid homeostasis. These results challenge the current view that they eye lacks lymphatic structures. Gou Young Koh and colleagues at Korea Advanced Institute of Science and Technology reveal that the presence of a lymphatic marker (PROX1) is indicative of proper of Schlemm's canal function and is absent under pathological conditions. Kari Alitalo and colleagues at the University of Helsinki show that a lymphatic growth factor (VEGF-C) reduces eye pressure and improves drainage through Schlemm's canal. In the companion commentary, Natalie Karpinich and Kathleen Caron indicate that the results from these studies many improve both therapeutics and diagnostics for glaucoma.

TITLE:

The Schlemm's canal is a VEGF-C/VEGFR-3 responsive lymphatic-like vessel

AUTHOR CONTACT:

Kari Alitalo
Biomedicum Helsinki; University of Helsinki, Helsinki, FIN
Phone: +358 9 191 25511; Fax: +358 9 191 25510; E-mail: kari.alitalo@helsinki.fi

View this article at:

http://www.jci.org/articles/view/75395?key=6b95849c28b310716341

ACCOMPANYING ARTICLE TITLE:

Lymphatic regulator PROX1 determines Schlemm's canal integrity and identity

AUTHOR CONTACT:

Gou Young Koh
Korea Advanced Institute of Science and Technology, Daejeon, , KOR
Phone: 82-42-350-2638; E-mail: gykoh@kaist.ac.kr

ACCOMPANYING COMMENTARY TITLE:

Schlemm's canal: more than meets the eye, lymphatics in disguise

AUTHOR CONTACT:

Kathleen M. Caron
The Univ. of North Carolina-Chapel Hill, Chapel Hill, NC, USA
Phone: (919) 966-5215; Fax: (919) 966-5230; E-mail: kathleen_caron@med.unc.edu

View this article at:

http://www.jci.org/articles/view/77507?key=e8b670be6c6be16f0505