Title: Salivary Cytokines and Toll Like Receptors in Chronic Periodontitis
Sharon Iype (Presenter)
Indiana University School of Dentistry
Mythily Srinivasan, Indiana University School of Dentistry
Objectives: Periodontitis is a set of inflammatory diseases affecting the periodontium. Early detection of inflammation before tissue destruction in periodontitis can improve the overall well-being of an individual. Since periodontitis is a biofilm-mediated host response, soluble and epithelial cell-associated markers of microbial recognition such as toll-like receptors (TLR) and salivary cytokines are altered. The aims are 1) to determine the salivary levels of pro-inflammatory Th1 (IL-12, INF-g), anti-inflammatory or Th2 cytokines (IL-4, IL-10) 2) to correlate the expression profiles of salivary epithelial cell-associated TLR-2 and TLR-4 receptors
Methods: Saliva samples were collected from thirty systemically healthy non-smokers diagnosed with severe chronic periodontitis. Patients exhibiting Clinical attachment loss (CAL) of ≥ 4mm in ≥ 30% of sites will be included in the generalized severe periodontitis group. Thirty systemically healthy non-smokers with no known conditions will be recruited as control subjects. All samples will be centrifuged at 250g for 15 minutes at 4°C. The cellular sediment obtained will be reconstituted in isotonic saline supplemented with two drops of Zap-O-globin to lyse blood corpuscles and centrifuged at 1400 rpm for 10 min at 4°C. The epithelial cell enriched preparation will then be assessed by light microscopy for morphology, reconstituted in RPMI 1640 supplemented with 5% fetal bovine and with 5% DMSO and stored at -80oC until further analysis. Enzyme-linked immunosorbent assay (ELISA) and flow cytometry will be performed for sTLR-2, sTLR-4 and cytokines.
Results: Measurable levels of IL-12 (pro-inflammatory), IL-4 (anti-inflammatory) concentrated IL-17 was present in healthy saliva. The concentration of sTLR-2 was significantly lower in the periodontitis saliva as compared with that in healthy saliva. Expression levels of TLR-2 mRNA was lower in salivary epithelial cells from periodontitis samples.
Conclusions: While salivary cytokines represent altered adaptive immune responses, assessment of sTLR in saliva may potentially indicate early innate immune changes in periodontitis.