Immunoregulatory Aspects of Periodontal Disease

Abstract

This manuscript reviews our studies of the composition and functional capabilities of gingival tissue lymphocytes from patients with periodontal disease. The emphasis has been on phenotyping the local lymphoid infiltration in gingival and periodontal disease. The preparation and phenotypic analyses of cells recovered from diseased and healthy human periodontal tissues indicated that T-cell subset ratios from diseased tissue were significantly decreased compared with peripheral blood or normal tissue ratios. These reductions were verified in a second study we performed using two-color immunofluorescence analyzed by flow cytofluorometry. Local variations in the CD4 + cell population were also found in diseased tissue cells when these were compared with normal tissue cells. The relative percentage of CD4+ cells labeled with anti-helper inducer (4B4) or anti-suppressor inducer (2H4) monoclonal antibodies was increased above that of normal tissue cells. Functional studies of immunoglobulin production by gingival cells from adult periodontitis tissues showed two discrete patterns of synthesis and also suppression of immunoglobulin synthesis after addition of mitogen to the cultures. Removal of macrophages also drastically reduced immunoglobulin synthesis by gingival cells. These results indicate that there is an abundance of suppressor T-cells in diseased tissue and that functional suppression is demonstrated by lymphocytes from periodontal disease tissue. The findings of these investigations have suggested potentially important roles for immune regulation in periodontal disease.