Treating Gum Disease With Immune Cells

The gingival inflammation and bone destruction of periodontal disease could be effectively treated by attracting the right kind of immune system cells to the inflamed tissues, according to a new animal study conducted by researchers at the University of Pittsburgh. Published in the early online version of the Proceedings of the National Academy of Sciences, the researchers’ findings offer a new therapeutic paradigm for a condition that afflicts 78 million people in the United States alone.

Significant evidence now shows that these diseased tissues are deficient in a subset of immune cells called regulatory T-cells, which tell attacking immune cells to stand down, stopping the inflammatory response. The scientists wanted to see what would happen if these regulatory T-cells were brought back to the gingival tissues. To do so, the researchers developed a system of polymer microspheres to slowly release a signaling protein called chemokine (Cys-Cys motif) ligand 22, or CCL22, that attracts regulatory T-cells. The scientists placed tiny amounts of the pastelike agent between the gums and teeth of animals with periodontal disease. The research team found that even though the amount of bacteria was unchanged, the treatment led to improvements of standard measures of periodontal disease, including decreased pocket depth and gingival bleeding, reflecting a reduction in inflammation as a result of increased numbers of regulatory T-cells. Also, microcomputed tomography scanning showed lower rates of bone loss.

(Source: EurekAlert!, November 4, 2013)