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Updated: Apr 1, 2026

Isolation of Human Lymphatic Endothelial Cells by Multi-parameter Fluorescence-activated Cell Sorting
Published on: May 1, 2015
Integrin Alpha-9 Mediates Lymphatic Valve Formation in Corneal Lymphangiogenesis
Eda Altiok1, Tatiana Ecoiffier1, Roberto Sessa1
1Vision Science Graduate Program, University of California, Berkeley, California, United States 2Center for Eye Disease and Development, Program in Vision Science, and School of Optometry, University of California, Berkeley, California, United States.
Purpose:
We recently reported that corneal lymphatic vessels develop integrin alpha-9 (Itga-9)-positive valves during inflammatory lymphangiogenesis. The purpose of this study was to further investigate the role of Itga-9 in corneal lymphatic valve formation in vivo and lymphatic endothelial cell (LEC) functions in vitro.
Methods:
Standard murine suture placement model was used to study the effect of Itga-9 blockade on lymphatic valve formation in vivo using Itga-9 neutralizing antibody. Whole-mount corneas were harvested for immunofluorescent microscopic analysis. Additionally, human LEC culture system was used to examine the effect of Itga-9 gene knockdown on cell functions using small interfering RNAs (siRNAs).
Results:
Itga-9 blockade in vivo significantly reduced the number of lymphatic valves formed in the inflamed cornea. Moreover, Itga-9 gene knockdown in human LECs suppresses cell functions of proliferation, adhesion, migration, and tube formation.
Conclusions:
Itga-9 is critically involved in corneal lymphatic valve formation. Further investigation of the Itga-9 pathway may provide novel strategies to treat lymphatic-related diseases occurring both inside and outside the eye.
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