Novel characterization and live imaging of Schlemm's canal expressing Prox-1.
Schlemm's canal is an important structure of the conventional aqueous humor outflow pathway and is critically involved in regulating the intraocular pressure. In this study, we report a novel finding that prospero homeobox protein 1 (Prox-1), the master control gene for lymphatic development, is expressed in Schlemm's canal. Moreover, we provide a novel in vivo method of visualizing Schlemm's canal using a transgenic mouse model of Prox-1-green fluorescent protein (GFP). The anatomical location of Prox-1⁺ Schlemm's canal was further confirmed by in vivo gonioscopic examination and ex vivo immunohistochemical analysis. Additionally, we show that the Schlemm's canal is distinguishable from typical lymphatic vessels by lack of lymphatic vessel endothelial hyaluronan receptor (LYVE-1) expression and absence of apparent sprouting reaction when inflammatory lymphangiogenesis occurred in the cornea. Taken together, our findings offer new insights into Schlemm's canal and provide a new experimental model for live imaging of this critical structure to help further our understanding of the aqueous humor outflow. This may lead to new avenues toward the development of novel therapeutic intervention for relevant diseases, most notably glaucoma.
Graduate Group in Vision Science, University of California, Berkeley, California, United States of America; Center for Eye Disease and Development, Program in Vision Science and School of Optometry, University of California, Berkeley, California, United States of America.
Tan N
TN
Truong
Center for Eye Disease and Development, Program in Vision Science and School of Optometry, University of California, Berkeley, California, United States of America.
Hannah
H
Li
Department of Surgery and Department of Biochemistry and Molecular Biology, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America.
Young-Kwon
YK
Hong
Graduate Group in Vision Science, University of California, Berkeley, California, United States of America; Center for Eye Disease and Development, Program in Vision Science and School of Optometry, University of California, Berkeley, California, United States of America; The Francis I. Proctor Foundation for Research in Ophthalmology, University of California San Francisco, San Francisco, California, United States of America; Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America.
Lu
L
Chen
D000818:Animals; D001082:Aqueous Humor / Q000502:physiology*; D003315:Cornea / Q000502:physiology / Q000648:ultrastructure; D015870:Gene Expression; D006023:Glycoproteins / Q000172:deficiency / Q000235:genetics; D006068:Gonioscopy; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D007150:Immunohistochemistry; D007429:Intraocular Pressure / Q000502:physiology*; D042583:Lymphangiogenesis / Q000502:physiology; D042601:Lymphatic Vessels / Q000502:physiology / Q000648:ultrastructure; D026901:Membrane Transport Proteins; D051379:Mice; D008822:Mice, Transgenic; D057054:Molecular Imaging; D011993:Recombinant Fusion Proteins / Q000235:genetics* / Q000378:metabolism; D012590:Sclera / Q000502:physiology / Q000648:ultrastructure; D014129:Trabecular Meshwork / Q000502:physiology / Q000648:ultrastructure; D025521:Tumor Suppressor Proteins / Q000235:genetics* / Q000378:metabolism; D000098551:Prospero-Related Homeobox 1 Protein
D006023:Glycoproteins; D049452:Green Fluorescent Proteins; D018398:Homeodomain Proteins; D026901:Membrane Transport Proteins; D011993:Recombinant Fusion Proteins; D025521:Tumor Suppressor Proteins; D000098551:Prospero-Related Homeobox 1 Protein; C492273:LYVE1 protein, mouse