Serum-Saliva CorrelationNA
Sensitivity0.07 pg/mL
Sample Test Volume60 μL
Recommended Collection Volume135 μL*
Special ConsiderationsNo
Collection ProtocolDownload PDF

​Interleukin-6 (IL-6) is one of a family of biologically active small protein molecules known as cytokines. It is released by a variety of tissues, including activated leukocytes, adipocytes, and endothelial cells, and it is involved in many processes in the body. IL-6 plays an important role in stimulating the immune response to infection or trauma by inducing the production of acute-phase proteins such as CRP and by fever induction. (1,2,3) In addition to its pro-inflammatory role, IL-6 also has anti-inflammatory properties. (4) Messenger RNA for IL-6 has been found in tissues of healthy human labial salivary glands, and the expression levels of the mRNAs were either up- or down-regulated by adjacent focal infiltrating lymphoid cells. The epithelial cells in the salivary glands are active participants in the autoimmune-mediated process of Sjögren’s syndrome, and salivary levels of IL-6 are increased in that disease. (5,6) Salivary IL-6 levels are also increased in periodontal disease. (7)

Researchers have found relationships between salivary IL-6 and sleep dysfunction, psychosocial factors, and stress. (8,9,10) A study with mice has shown that normal parotid acinar cells synthesize IL-6 and store it in secretory granules. The IL-6 is released from the granules following α- and β-adrenergic stimulation. (11)​

  • McCarty, M.F. (1999). Interleukin-6 as a central mediator of cardiovascular risk associated with chronic inflammation, smoking, diabetes, and visceral obesity: Down-regulation with essential fatty acids, ethanol and pentoxifylline. Med Hypotheses, 52(5), 465-77.
  • Castell, J.V., Gomez-Lechon, M.J., David, M., et al. (1990). Acute-phase response of human hepatocytes: Regulation of acute-phase protein synthesis by interleukin-6. Hepatology, 12(5), 1179-86.
  • Chai, Z., Gatti, S., Toniatti, C., et al. (1996). Interleukin (IL)-6 gene expression in the central nervous system is necessary for fever response to lipopolysaccharide or IL-1β: A study on IL-6-deficient mice. J Exp Med, 183(1), 311-16.
  • Tilg, H., Trehu, E., Atkins, M.B. (1994). Interleukin-6 (IL-6) as an anti-inflammatory cytokine: Induction of circulating IL-1 receptor antagonist and soluble tumor necrosis factor receptor p55. Blood, 83(1), 113-18.
  • Sun, D., Emmert-Buck, M.R., Fox, P.C. (1998). Differential cytokine mRNA expression in human labial minor salivary glands in primary Sjögren’s syndrome. Autoimmunity, 28(3), 125-37.
  • Tishler, M., Yaron, I., Shirazi, I., et al. (1999). Increased salivary interleukin-6 levels in patients with primary Sjögren’s syndrome. Rheumatol Int, 18(4), 125-27.
  • Costa, P.P., Trevisan, G.L., Macedo, G.O., et al. (2010). Salivary interleukin-6, matrix metalloproteinase-8, and osteoprotegerin in patients with periodontitis and diabetes. J Periodontology, 81(3), 384-91.
  • El-Sheikh, M., Buckhalt, J.A., Granger, D.A., et al. (2007). The association between children’s sleep disruption and salivary interleukin-6. J Sleep Res, 16(2), 188-97.
  • Sjögren, E., Leanderson, P., Kristenson, M., Ernerudh, J. (2006). Interleukin-6 levels in relation to psychosocial factors: Studies on serum, saliva, and in vitro production by blood mononuclear cells. Brain Behav Immun, 20(3), 270-78.
  • Groer, M., Murphy, r., bunnell, W., et al. (2010). Salivary measures of stress and immunity in police officers engaged in simulated critical incident scenarios. J Occup Environ Med, 52(6), 595-602.
  • Tanda, N., Ohyama, H., Yamakawa, M., et al. (1998). IL-1β and IL-6 in mouse parotid acinar cells: Characterization of synthesis, storage, and release. Am J Physiol, 274(1 Pt 1), G147-56.