Relationship between the presence of periodontopathic bacteria and the expression of chemokine receptor mRNA in inflamed gingival tissues.

BACKGROUND AND OBJECTIVE

Periodontal disease is a chronic disease characterized by the interaction between periodontopathic bacteria and the host immune response. The aim of this study was to investigate the correlation between periodontopathic bacteria and host immune cell infiltrates.

MATERIAL AND METHODS

Twenty-two patients with chronic periodontitis were included in this study. Gingival tissues were taken at the periodontal surgery after completion of initial therapy. Three types of periodontopathic bacteria were detected by polymerase chain reaction, and the prevalence of mRNA expression of chemokine receptors was examined by reverse-transcription-polymerase chain reaction in the gingival tissues. The infiltration of T and B cells was determined by an immunohistochemical method.

RESULTS

In the patients, both Porphyromonas gingivalis and Tanerella forsythia were detected, and the mRNA expression of chemokine receptors CXCR1&2, CXCR4, CCR1, CCR2, CCR3 and CCR4 were more prevalent. The mean number of infiltrated B cells was significantly larger than that of T cells in the sites harboring both P. gingivalis and T. forsythia. Similarly, in the sites where P. gingivalis was detected but T. forsythia was not, the mean number of B cells was significantly larger than that of T cells. In the sites with mRNA expression of CCR2 and CCR3, the mean number of B cells was significantly larger.

CONCLUSION

These results suggest that a high proportion of T helper 2-associated chemokine receptor-positive T cells may be associated with the predominance of B cells and may play an important role in the formation of chronic periodontitis in sites where both P. gingivalis and T. forsythia are detected.