title: Validation of Salivary Interleukin-6 and Tumor Necrosis Factor-Alpha of Healthy Adult Volunteers by Enzyme Immunoassay.
abstract: BACKGROUND
  Despite the use of saliva with enzyme immunoassay (EIA) methods validated for use with blood to measure interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), there has been limited validation of saliva as a matrix for EIA of IL-6 and TNF-α.
  
  
  OBJECTIVE
  The study aims were to (a) validate one vendor's commercially available EIAs for detecting IL-6 and TNF-α in saliva as an alternative matrix to blood and (b) test the long-term stability of EIA detection of IL-6 and TNF-α after 12-month storage of saliva and plasma.
  
  
  METHODS
  Spike and recovery and linearity experiments were performed. Concentrations of IL-6 and TNF-α in saliva and plasma from 20 healthy adult volunteers (6 men and 14 women) were correlated; the assays were repeated 12 months later.
  
  
  RESULTS
  Spike and recovery and linearity performance was adequate for salivary IL-6: intra-assay percentage coefficient of variation, less than or equal to 8.4%; sensitivity, 0.11 pg/ml; mean recoveries, 81% in spiked saliva and 110% in spiked controls; and linearity, r = .995. The association between IL-6 in saliva and plasma was moderate and significant (p = .04). Spike and recovery and linearity performance was inadequate for TNF-α: intra-assay coefficient of variation, 10.8%; sensitivity, 2.3 pg/ml; mean recoveries, 44% in spiked saliva and 92% in spiked controls; and linearity, r = .950. The association between TNF-α in saliva and plasma was low and insignificant. Plasma and saliva IL-6 levels were significantly higher (p < .0001), and plasma and saliva TNF-α levels were significantly lower (p < .0001) after 12-month storage of specimens.
  
  
  CONCLUSIONS
  We concluded that (a) saliva can be used to assess IL-6, but not TNF-α, with an EIA validated for use with blood and (b) 12-month storage of plasma and saliva significantly changes the assay results. Validation of other EIAs would expand assay options for investigators.
authors: Sandra K. Hanneman, PhD, RN, FAAN, is Jerold B. Katz Distinguished Professor for Nursing Research, Department of Acute and Continuing Care, The University of Texas Health Science Center at Houston School of Nursing. David McCue, BS, at the time this research was conducted, he was Laboratory Manager, Biosciences Laboratory, Center for Nursing Research, The University of Texas Health Science Center at Houston School of Nursing. He is now Coordinator of Clinical Studies, Department of Leukemia, MD Anderson Cancer Center, Houston, Texas. Gabriel L. Blog, BSN, MS, RN, at the time this research was conducted, he was BSN Honors Program Student, Biosciences Laboratory, Center for Nursing Research, The University of Texas Health Science Center at Houston School of Nursing. He is now DNP Student, Nurse Anesthesia Program, University of Texas Health Science Center, Houston.
authors: Sandra K
authors: SK
authors: Hanneman
authors: David
authors: D
authors: McCue
authors: Gabriel L
authors: GL
authors: Blog
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D015850:Interleukin-6 / Q000032:analysis* / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012463:Saliva / Q000737:chemistry*; D013781:Texas; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis* / Q000097:blood*; D055815:Young Adult
chemical_list: D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha