The normal human choroid is endowed with a significant number of lymphatic vessel endothelial hyaluronate receptor 1 (LYVE-1)-positive macrophages

Invest Ophthalmol Vis Sci. 2008 Dec;49(12):5222-9. doi: 10.1167/iovs.08-1721. Epub 2008 Aug 8.

Abstract

Purpose: Lymphatic vessel endothelial hyaluronic acid receptor (LYVE-1) is a newly discovered lymphatic endothelium-specific marker that is also expressed by a subpopulation of macrophages. To date, there is no report on its expression in the posterior human uvea. The purpose of this study was to investigate the expression of LYVE-1 in normal human choroids.

Methods: Eyes of body/cornea donors (55-89 years of age; 4-9 hours postmortem) were obtained. Choroids were dissected and prepared for cryosections followed by immunohistochemistry with anti-human LYVE-1 antiserum and immunogold labeling. In addition, anti-human antibodies against macrophage markers (CD68, MHC class II) and lymphatic (podoplanin) and blood vascular endothelium (CD31, vWF) were used. For documentation, light-, fluorescence-, confocal laser scanning-, and electron-microscopy were used.

Results: The normal human choroidal stroma contained 274 +/- 86 LYVE-1 positive cells/mm(2). The cells displayed irregular shapes with a relatively uniform diameter of 32 mum. Costaining with CD68 and negativity for CD31, podoplanin, and melan-A/HMB45, as well as electron microscopic features, suggest these LYVE-1(+) cells to be macrophages. Besides that, no classic LYVE-1(+)/podoplanin(+) lymphatic vessels were detected within the normal adult human choroid.

Conclusions: The normal adult human choroid does not contain typical lymph vessels, but is endowed with a significant number of LYVE-1 positive macrophages. These cells may be involved in choroidal hyaluronic acid metabolism or contribute to temporary formation of lymphatic channels under inflammatory conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Antigens, CD / metabolism
  • Antigens, Differentiation, Myelomonocytic / metabolism
  • Biomarkers
  • Choroid / metabolism*
  • Fluorescent Antibody Technique, Indirect
  • Histocompatibility Antigens Class II / metabolism
  • Humans
  • Lymphatic Vessels / physiology
  • Macrophages / metabolism*
  • Membrane Glycoproteins / metabolism
  • Microscopy, Confocal
  • Microscopy, Immunoelectron
  • Middle Aged
  • Platelet Endothelial Cell Adhesion Molecule-1 / metabolism
  • Vesicular Transport Proteins / metabolism*
  • von Willebrand Factor / metabolism

Substances

  • Antigens, CD
  • Antigens, Differentiation, Myelomonocytic
  • Biomarkers
  • CD68 antigen, human
  • Histocompatibility Antigens Class II
  • LYVE1 protein, human
  • Membrane Glycoproteins
  • PDPN protein, human
  • Platelet Endothelial Cell Adhesion Molecule-1
  • Vesicular Transport Proteins
  • von Willebrand Factor