Lymphoid and inflammatory chemokine expression in chronic periodontitis lesions

Objectives: In B-cell dominant periodontitis lesion, a variety of inflammatory cells is recruited and plays roles in tissue destruction as well as protection. Chemokines and their receptors regulate cell migration in both healthy and inflammatory conditions. Each subset of immune cells expresses characteristic chemokine receptors. The aim of this study is to examine the expression of inflammatory and tissue homing chemokines and their receptors in chronic inflammatory periodontal lesions.

Methods: Twenty-three gingival tissues of chronic periodontitis and 20 gingival tissues of healthy/ gingivitis periodontitis tissues were analysed. Gene expression of lymphoid chemokines CCL21, CXCL13, inflammatory chemokines CCL5, CCL22, CCL20, their receptors CCR7, CXCR5, CCR4, CCR6, and cytokines IL-10, IL17A in the gingival tissues was examined by RT-real-time PCR.

Results: Gene expressions of CD19, CXCL13, CCL21, CCL5, IL-10, IL-17A , CXCR5, and CCR4 were significantly higher in periodontitis than in gingivitis. The expression levels of CCL22, CCL20, CCR7, and CCR6 did not differ significantly between periodontitis and gingivitis. The expression levels of CXCL13, CXCR5, CCL5, CCR7, and CCR6 correlated with that of CD19 significantly. On the other hand, IL17A and CCR4 expression did not correlate with CD19 expression. CCR4 expression did not correlate with its ligand CCL22, but moderately associated with IL-10.

Conclusion: These findings suggest that increased B-cell infiltration is associated with increase of both lymphoid and inflammatory chemokines. Not all B-cell dominant periodontitis lesions seem to contain a considerable number of Th2 and Th17 cells.

This work was supported by Grant-in Aids for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan and Grant for Promotion of Niigata University Research Projects.