Detection of local and systemic cytokines in adult periodontitis

Periodontitis is a chronic inflammatory disease of the soft and hard supporting tissues of the teeth and is a major cause of tooth loss in adults. The local host response to periodontopathic bacteria results in the release of inflammatory mediators and cytokines. Since cytokines are indicative of effector functions, we compared the pattern of cytokine production in periodontal patients and healthy controls. Specifically, we investigated the simultaneous presence of cytokines produced by T helper (Th)1, Th 2, and inflammatory cells which could be involved in periodontitis. We also compared the expression of these cytokine mRNAs in healthy and diseased tissues. No significant differences were detected at the protein or mRNA levels of the cytokines in the systemic circulation of patients and controls. The surface markers CD16 and CD56 were expressed on significantly fewer peripheral mononuclear cells of patients when compared to controls. gamma delta + T cells were found in half of the diseased tissues, but in none of the healthy tissues of either patients or controls. Finally, significant differences were observed between healthy and inflamed gingival tissues in the cytokine mRNA profile. Expression of IL-6 and IFN-alpha mRNA was significantly higher in diseased tissues compared to healthy tissues in patients.