title: Endothelial L-selectin ligand expression in nasal polyps.
abstract: BACKGROUND
  L-selectins on leukocytes and their counter-receptors on endothelial cells have been shown to be involved in leukocyte recruitment in chronic rhinosinusitis without nasal polyps (NP).
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the expression level of functionally active endothelial L-selectin ligands in NP obtained from patients with NP of different etiology [simple NP, antro-choanal polyps (ACP) and cystic fibrosis (CF) NP] and inferior turbinate specimens of healthy controls and to compare these levels to the presence of various leukocyte subsets.
  
  
  METHODS
  Nasal polyp specimens and healthy nasal mucosa specimens were obtained from patients undergoing surgery and were immunohistochemically stained with monoclonal antibodies detecting CD34, sialyl Lewis x (sLe(x)) of sulfated extended core 1 lactosamines and various leukocyte subsets.
  
  
  RESULTS
  All NP are characterized by a decrease in the number of CD34+ vessels. The number of eosinophils and the percentage of vessels expressing endothelial sulfated sLe(x) epitopes is upregulated in all groups of simple NP. Tissue eosinophilia is increased in those patients with increased disease severity (acetyl salicylic acid intolerance), but the percentage of endothelial sulfated sLe(x) epitopes is not. Results on CF NP are similar to those observed for simple NP. Antro-choanal polyps, on the contrary, are characterized by low numbers of tissue eosinophils and relatively few vessels expressing endothelial sulfated sLe(x) epitopes.
  
  
  CONCLUSIONS
  Our results suggest that functionally active L-selectin ligands might play a role in guiding leukocyte traffic into NP in patients with simple NP and CF NP but not ACP.
authors.affiliation: Department of Otorhinolaryngology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Fenna A
authors.initials: FA
authors.lastname: Ebbens
authors.forename: S K
authors.initials: SK
authors.lastname: Toppila-Salmi
authors.forename: J A
authors.initials: JA
authors.lastname: Renkonen
authors.forename: R L O
authors.initials: RL
authors.lastname: Renkonen
authors.forename: J
authors.initials: J
authors.lastname: Mullol
authors.forename: C M
authors.initials: CM
authors.lastname: van Drunen
authors.forename: W J
authors.initials: WJ
authors.lastname: Fokkens
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018952:Antigens, CD34 / Q000096:biosynthesis / Q000276:immunology; D001249:Asthma / Q000150:complications / Q000276:immunology / Q000378:metabolism; D001491:Basophils / Q000276:immunology / Q000378:metabolism; D002634:Chemotaxis, Leukocyte / Q000276:immunology*; D042783:Endothelial Cells / Q000276:immunology / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019041:L-Selectin / Q000276:immunology / Q000378:metabolism*; D007962:Leukocytes / Q000276:immunology* / Q000378:metabolism; D008024:Ligands; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D008297:Male; D008407:Mast Cells / Q000276:immunology / Q000378:metabolism; D008875:Middle Aged; D009297:Nasal Mucosa / Q000276:immunology / Q000378:metabolism; D009298:Nasal Polyps / Q000150:complications / Q000276:immunology / Q000378:metabolism*; D009844:Oligosaccharides / Q000096:biosynthesis / Q000276:immunology; D000080506:Sialyl Lewis X Antigen
chemical_list: D018952:Antigens, CD34; D008024:Ligands; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; D019041:L-Selectin