title: Myeloid-Related Protein-14/MRP-14/S100A9/Calgranulin B is Associated with Inflammation in Proliferative Diabetic Retinopathy.
abstract: OBJECTIVE
  To investigate the expression of the leukocyte proteins myeloid-related protein (MRP)-8 and MRP-14 in proliferative diabetic retinopathy (PDR) and the effect of MRP-8/MRP-14 (calprotectin) heterodimer on induction of proinflammatory factors in human retinal microvascular endothelial cells (HRMEC).
  
  
  METHODS
  Epiretinal membranes from 20 patients with PDR and 10 patients with proliferative vitreoretinopathy (PVR), vitreous fluid samples from PDR and non-diabetic subjects and HRMEC were studied by immunohistochemistry and Western blot analysis.
  
  
  RESULTS
  MRP-14 expression was localized in endothelial cells, leukocytes and myofibroblasts in all PDR membranes. MRP-8 expression was limited to intravascular leukocytes in 42% of the studied membranes. In PVR membranes, MRP-14 was expressed in leukocytes and myofibroblasts, whereas MRP-8 immunoreactivity was limited to leukocytes. MRP-14 was significantly upregulated in vitreous from PDR patients. MRP-8/MRP-14 (calprotectin) increased expression of intercellular adhesion molecule-1, but attenuated vascular cell adhesion molecule-1 expression in HRMEC.
  
  
  CONCLUSIONS
  Increased MRP-14 levels are associated with inflammation in PDR.
authors.affiliation: a Department of Ophthalmology , College of Medicine, King Saud University , Riyadh , Saudi Arabia.|b Dr Nasser Al-Rashid Research Chair in Ophthalmology , Riyadh , Saudi Arabia.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Abu El-Asrar
authors.affiliation: a Department of Ophthalmology , College of Medicine, King Saud University , Riyadh , Saudi Arabia.
authors.forename: Kaiser
authors.initials: K
authors.lastname: Alam
authors.affiliation: a Department of Ophthalmology , College of Medicine, King Saud University , Riyadh , Saudi Arabia.
authors.forename: Mohammad M
authors.initials: MM
authors.lastname: Siddiquei
authors.affiliation: c Laboratory of Histochemistry and Cytochemistry, University of Leuven , KU Leuven , Leuven , Belgium.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Van den Eynde
authors.affiliation: a Department of Ophthalmology , College of Medicine, King Saud University , Riyadh , Saudi Arabia.
authors.forename: Ghulam
authors.initials: G
authors.lastname: Mohammad
authors.affiliation: c Laboratory of Histochemistry and Cytochemistry, University of Leuven , KU Leuven , Leuven , Belgium.
authors.forename: Gert
authors.initials: G
authors.lastname: De Hertogh
authors.affiliation: d Laboratory of Immunobiology, Rega Institute for Medical Research, Department of Microbiology and Immunology , University of Leuven , KU Leuven , Leuven , Belgium.
authors.forename: Ghislain
authors.initials: G
authors.lastname: Opdenakker
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D015153:Blotting, Western; D040502:Calgranulin B / Q000096:biosynthesis*; D002478:Cells, Cultured; D003930:Diabetic Retinopathy / Q000378:metabolism* / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007249:Inflammation / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D014822:Vitreous Body / Q000378:metabolism / Q000473:pathology*
chemical_list: D015415:Biomarkers; D040502:Calgranulin B
keywords: Inflammation; leukocytes; myeloid-related proteins 8 and 14; proliferative diabetic retinopathy; proliferative vitreoretinopathy