title: Peripheral blood mononuclear cells of patients with systemic sclerosis produce increased amounts of interleukin 6, but not transforming growth factor beta 1.
abstract: OBJECTIVE
  To assess the ability of peripheral blood mononuclear cells (PBMC) of patients with systemic sclerosis (SSc) to produce interleukin 6 (IL-6), transforming growth factor beta 1 (TGF-beta 1), to identify the IL-6 producer cells in the in vitro model, and to correlate these data with the clinical evidence of our patients.
  
  
  METHODS
  We used a sandwich ELISA to quantitate IL-6 and TGF-beta 1 levels in sera, plasma, and supernatants, and an imunofluorescence technique to evaluate IL-6 producing cells in our patients.
  
  
  RESULTS
  IL-6 was detected in sera from 8 of 20 patients and no controls (p < 0.05). A significant increase of IL-6 production was observed in both spontaneous and phytohemagglutinin (PHA) induced cultures of PBMC from patients with SSc vs controls. No differences in TGF-beta 1 production were observed, either in sera or supernatants, between patients and controls. A significant increase of IL-6 synthesizing cells was observed after 3 h of PHA stimulation in patients vs controls (p < 0.05).
  
  
  CONCLUSIONS
  Spontaneous IL-6 production and the higher number of IL-6 producing cells in patients with SSc suggest that these cells have been already primed in vivo. The absence of PBMC primed for TGF-beta 1 production supports the hypothesis that cells other than lymphocytes produce and secrete this cytokine in the skin of patients. Higher serum levels of IL-6 observed in a subset of patients did not correlate with either severity or duration of disease.
authors.affiliation: Department of Internal Medicine, University of L'Aquila School of Medicine, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Giacomelli
authors.forename: P
authors.initials: P
authors.lastname: Cipriani
authors.forename: C
authors.initials: C
authors.lastname: Danese
authors.forename: F
authors.initials: F
authors.lastname: Pizzuto
authors.forename: R
authors.initials: R
authors.lastname: Lattanzio
authors.forename: I
authors.initials: I
authors.lastname: Parzanese
authors.forename: A
authors.initials: A
authors.lastname: Passacantando
authors.forename: M A
authors.initials: MA
authors.lastname: Perego
authors.forename: G
authors.initials: G
authors.lastname: Tonietti
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000097:blood; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism*; D012595:Scleroderma, Systemic / Q000097:blood*; D016212:Transforming Growth Factor beta / Q000096:biosynthesis* / Q000097:blood
chemical_list: D015850:Interleukin-6; D016212:Transforming Growth Factor beta