Macrophage Inflammatory Protein 3α–CC chemokine receptor 6 interactions play an important role in CD4+ T-cell accumulation in periodontal diseased tissu

Abstract

SUMMARY The regulatory role of chemokines and chemokine receptors on specific lymphocyte recruitment into periodontal diseased tissue is poorly characterized. We observed that lymphocytes infiltrating inflamed gingival tissue expressed marked levels of CCR6. In periodontal diseased tissue, the expression of MIP-3α mRNA was detected by RT-PCR and further, MIP-3α was distributed in the basal layer of gingival epithelial cells, microvascular endothelial cells and the areas of inflammatory cells as shown by immunohistochemistry. Moreover, CCR6-expressing cells infiltrated into periodontal diseased tissue, and the proportion of CCR6-positive CD4+ T cells was significantly elevated in periodontal diseased tissue compared with peripheral blood in the same patients. Furthermore, gingival lymphocytes isolated from patients showed migration toward MIP-3α in an in vitro chemotaxis assay in which migration was abrogated by specific antibody to CCR6. Thus, these findings suggested that CCR6 and the corresponding chemokine, MIP-3α may have an important regulatory role in specific lymphocyte migration into inflamed periodontal tissue.