Research & Innovation
Publications
Topography of Lymphatic Markers in Human Iris and Ciliary Body
PMU Authors
A. Kaser-Eichberger, F. Schrödl, A. Trost, C. Strohmaier, B. Bogner, C. Runge, D. Bruckner, M. Laimer, L. M. Heindl, H. A. Reitsamer
All Authors
A. Kaser-Eichberger, F. Schrödl, A. Trost, C. Strohmaier, B. Bogner, C. Runge, K. Motloch, D. Bruckner, M. Laimer, S. L. Schlereth, L. M. Heindl, H. A. Reitsamer
Journal association
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
Abstract
PURPOSE: Reports of lymphatics in the anterior human uvea are contradictory. This might be caused due to a certain topography, which has not been considered yet. Therefore, here we systematically analyze iris and adjacent ciliary body with immunohistochemistry by combining various lymphatic markers. METHODS: Human iris and ciliary body were obtained from cornea donors and prepared for cryosectioning. Cross sections of tissue blocks at 12/3/6/9 o'clock position and at corresponding intersections (1:30/4:30/7:30/10:30) were processed for immunohistochemistry of LYVE-1, PDPN, PROX1, FOXC2, VEGFR3, and CCL21, and when necessary, these lymphatic markers were combined with CD31, α-smooth muscle-actin, CD68, and 4',6-diamidino-2 phenylindole dihydrochloride (DAPI). Double, triple, and quadruple marker combinations were documented using confocal microscopy. RESULTS: Numerous podoplanin+ cells were mainly located at the anterior border of the iris while LYVE-1+ cells were distributed throughout the nonpigmented part. Both cell populations were PROX1/FOXC2/CCL21/VEGFR3-. Blood vessels, iris smooth muscles, and individual cells were VEGFR3+. While PDPN+ cells were rarely detected posteriorly of the iris root, many LYVE-1+ cells were present within the ciliary body muscle and villi. Within the muscle, occasionally PDPN+ vessel-like structures were detectable, but these were never colocalized with LYVE-1. Similar vessel-like structures were VEGFR3+/PROX1-/CCL21-, but CD31+. Further, ciliary muscle fibers and ciliary epithelium were immunoreactive for VEGFR3/CCL21, but were LYVE-1/PDPN-. A certain topography of structures at the various uvea-positions investigated was not obvious. The majority of LYVE-1+ cells displayed immunoreactivity for CD68. CONCLUSIONS: Lymphatic vessels colocalizing for at least two lymphatic markers were not detectable. Therefore, if present, putative lymphatic channels of the anterior uvea might display a different marker panel than generally presumed.
Keywords
Aged Ciliary Body/*blood supply/metabolism Corneal Diseases/metabolism/pathology Endothelium, Lymphatic/metabolism/pathology Female Humans Immunohistochemistry Iris/*blood supply/metabolism Lymphatic Vessels/metabolism/*pathology Male Membrane Glycoproteins Microscopy, Confocal Microscopy, Immunoelectron Middle Aged