Salivary cytokine profiles in primary Sjögren's syndrome differ from those in non-Sjögren sicca in terms of TNF-α levels and Th-1/Th-2 ratios

Clin Exp Rheumatol. Nov-Dec 2011;29(6):970-6. Epub 2011 Dec 22.

Abstract

Objectives: To compare salivary cytokine profiles in patients with primary Sjögren's syndrome (pSS), non-SS sicca controls, and non-sicca controls, and to investigate whether cytokine levels are correlated with clinical parameters of pSS patients.

Methods: Un-stimulated whole saliva samples were obtained from pSS patients (n=30) classified according to the criteria of the American European Consensus Group. Age- and gender-matched non-SS sicca patients (n=30) and non-sicca subjects (n=25) served as controls. Salivary IFN-γ, TNF-α, IL-1, IL-4, IL-6, IL-10, IL-12p40, and IL-17 levels were measured using a multiplex Luminex® bead-based assay.

Results: pSS patients and non-SS sicca controls had significantly lower salivary flow rates (SFRs) than non-sicca controls, and pSS patients showed a more profound decrease than non-SS sicca controls. In addition, pSS patients and non-SS sicca controls had higher levels of IFN-γ, TNF-α, IL-1, IL-4, IL-10, IL-12p40, and IL-17 in their saliva than non-sicca controls. Salivary TNF-α levels were higher in pSS patients than in non-SS sicca controls. Th-1/Th-2 ratios, represented by INF-γ/IL-4 and TNF-α /IL-4 ratios, were significantly higher in pSS patients than in non-SS sicca controls. SFR was found to be correlated with INF-γ/IL-4 ratio (r=0.411 p=0.024), and focus score to be correlated with TNF-α/IL-4 ratio (r=0.581, p=0.023) in pSS patients.

Conclusions: Th-1, Th-2, and Th17 cytokine levels were found to be elevated in the saliva of pSS patients compared with non-sicca controls. However, considerable overlap was observed between the salivary cytokine levels of pSS patients and of non-SS sicca controls. The features that most differentiated pSS and non-SS sicca were higher TNF-α levels and Th-1/Th-2 ratios. Th-1/Th-2 ratio was also found to be correlated with the clinical parameters of pSS.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cytokines / metabolism*
  • Female
  • Humans
  • Interferon-gamma / metabolism
  • Interleukin-4 / metabolism
  • Keratoconjunctivitis Sicca / diagnosis
  • Keratoconjunctivitis Sicca / metabolism
  • Male
  • Middle Aged
  • Saliva / metabolism
  • Salivary Glands / metabolism*
  • Salivary Glands / pathology
  • Salivary Glands / physiopathology
  • Secretory Rate
  • Sjogren's Syndrome / diagnosis
  • Sjogren's Syndrome / metabolism*
  • T-Lymphocytes, Helper-Inducer / metabolism
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Cytokines
  • Tumor Necrosis Factor-alpha
  • Interleukin-4
  • Interferon-gamma