title: Expression and function of toll-like receptors in peripheral blood mononuclear cells of patients with polymyalgia rheumatica and giant cell arteritis.
abstract: OBJECTIVE
  To investigate the expression and function of the Toll-like receptor (TLR) family in peripheral blood mononuclear cells (PBMCs) of patients with polymyalgia rheumatica (PMR) and giant cell arteritis (GCA).
  
  
  METHODS
  The authors analysed 70 patients with PMR, 20 with GCA, and 24 healthy controls (HC). TLR expression was assessed by flow cytometry. TLR function was assessed by stimulating PBMCs with specific ligands.
  
  
  RESULTS
  A significantly increased expression of TLR7 in PBMCs of patients with active disease compared with HC was found. Despite increased expression of TLR7, circulating monocytes from patients showed a significantly lower in vitro response to TLR7 agonists. No amino acid substitutions predicted to be functionally damaging were found in TLR7. A normal response to specific TLR7 agonists in patients in complete remission eliminated a genetic defect. TLR expression and function were also affected to some degree in other diseases characterised by a strong acute phase response.
  
  
  CONCLUSIONS
  These data suggest activation of TLR7 during the active phase of PMR and GCA which resolves with complete disease remission. Whether this finding is the consequence of the marked inflammatory process in these disorders or activation by natural ligands remains to be explored.
authors.affiliation: Servicio de Reumatología, Universidad de Cantabria, Hospital Universitario Marqués de Valdecilla-IFIMAV, Santander, Spain.
authors.forename: Lorena
authors.initials: L
authors.lastname: Álvarez Rodríguez
authors.forename: Marcos
authors.initials: M
authors.lastname: López-Hoyos
authors.forename: Cristina
authors.initials: C
authors.lastname: Mata
authors.forename: Ana
authors.initials: A
authors.lastname: Fontalba
authors.forename: Jaime
authors.initials: J
authors.lastname: Calvo Alen
authors.forename: María José
authors.initials: MJ
authors.lastname: Marín
authors.forename: José Luis
authors.initials: JL
authors.lastname: Fernández-Luna
authors.forename: Jesús
authors.initials: J
authors.lastname: Aguero Balbín
authors.forename: Maitane
authors.initials: M
authors.lastname: Aranzamendi Zaldunbide
authors.forename: Ricardo
authors.initials: R
authors.lastname: Blanco
authors.forename: Víctor M
authors.initials: VM
authors.lastname: Martínez-Taboada
mesh_terms: D000208:Acute Disease; D000210:Acute-Phase Reaction / Q000276:immunology; D000368:Aged; D000369:Aged, 80 and over; D001402:B-Lymphocytes / Q000276:immunology; D016022:Case-Control Studies; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D013700:Giant Cell Arteritis / Q000188:drug therapy / Q000276:immunology*; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000276:immunology; D011111:Polymyalgia Rheumatica / Q000188:drug therapy / Q000276:immunology*; D012074:Remission Induction; D013601:T-Lymphocytes / Q000276:immunology; D051199:Toll-Like Receptor 7 / Q000097:blood / Q000276:immunology; D051193:Toll-Like Receptors / Q000097:blood* / Q000276:immunology
chemical_list: D016207:Cytokines; D005938:Glucocorticoids; D018836:Inflammation Mediators; C495348:TLR7 protein, human; D051199:Toll-Like Receptor 7; D051193:Toll-Like Receptors