title: CD81 and CD48 show different expression on blood eosinophils in systemic sclerosis: new markers for disease and pulmonary inflammation?
abstract: OBJECTIVE
  In systemic sclerosis (SSc)-related interstitial lung disease (ILD), elevated eosinophil counts in bronchoalveolar lavage are associated with a worse outcome. We hypothesized that eosinophils may be activated in the peripheral circulation, thereby increasing their recruitment to affected tissues and contributing to inflammation and fibrosis. The aim of this study was to characterize the blood eosinophils in SSc patients.
  
  
  METHODS
  Expression levels of surface markers CD11b, CD44, CD48, CD54, CD69, CD81, and HLA-DR on CD16(low)CD9(high)-expressing eosinophils were measured by flow cytometry in whole blood from SSc patients (n = 32) and controls (n = 11).
  
  
  RESULTS
  Expression levels of CD54, CD69, and HLA-DR were undetectable in all groups. CD44 and CD11b expression levels were similar between groups. CD81 expression was lower in patients compared to controls independent of disease duration (p = 0.001). CD48 expression was increased in patients with a short disease duration (< 2 years) compared to both controls (p = 0.042) and patients with longer disease duration (≥ 2 years; p = 0.027). In patients with short disease duration, increased CD48 expression was associated with alveolar inflammation as measured by an increased concentration of alveolar nitric oxide (r = 0.76, p = 0.003).
  
  
  CONCLUSIONS
  Blood eosinophils change phenotype during disease evolution in SSc, and CD48 expression may be used as a biomarker for pulmonary inflammation.
authors.affiliation: a Section of Rheumatology, Department of Clinical Sciences, Lund University and Skåne University Hospital , Lund , Sweden.
authors.forename: D M
authors.initials: DM
authors.lastname: Wuttge
authors.affiliation: b Section of Microbiology, Immunology and Glycobiology, Department of Laboratory Medicine, Lund University and Skåne University Hospital , Lund , Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Andreasson
authors.affiliation: c Section of Respiratory Medicine and Allergy, Department of Clinical Sciences, Lund University and Skåne University Hospital , Lund , Sweden.
authors.forename: E
authors.initials: E
authors.lastname: Tufvesson
authors.affiliation: b Section of Microbiology, Immunology and Glycobiology, Department of Laboratory Medicine, Lund University and Skåne University Hospital , Lund , Sweden.
authors.forename: Å C M
authors.initials: ÅC
authors.lastname: Johansson
authors.affiliation: a Section of Rheumatology, Department of Clinical Sciences, Lund University and Skåne University Hospital , Lund , Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Scheja
authors.affiliation: d Section of Nephrology, Department of Clinical Sciences, Lund, Lund University and Skåne University Hospital , Lund , Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Hellmark
authors.affiliation: a Section of Rheumatology, Department of Clinical Sciences, Lund University and Skåne University Hospital , Lund , Sweden.
authors.forename: R
authors.initials: R
authors.lastname: Hesselstrand
authors.affiliation: b Section of Microbiology, Immunology and Glycobiology, Department of Laboratory Medicine, Lund University and Skåne University Hospital , Lund , Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Truedsson
mesh_terms: D000368:Aged; D015703:Antigens, CD / Q000378:metabolism*; D015415:Biomarkers; D000071178:CD48 Antigen; D016022:Case-Control Studies; D004804:Eosinophils / Q000378:metabolism*; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism; D010641:Phenotype; D011658:Pulmonary Fibrosis / Q000209:etiology / Q000378:metabolism*; D045743:Scleroderma, Diffuse / Q000378:metabolism; D045745:Scleroderma, Limited / Q000378:metabolism; D012595:Scleroderma, Systemic / Q000150:complications / Q000378:metabolism*; D060225:Tetraspanin 28 / Q000378:metabolism*; D013997:Time Factors
chemical_list: D015703:Antigens, CD; D015415:Biomarkers; D000071178:CD48 Antigen; C000604065:CD48 protein, human; C554798:CD81 protein, human; D060225:Tetraspanin 28; D009569:Nitric Oxide