Lymphocyte function in early-onset periodontitis
This is a limited review of recent research on the role of lymphocytes in early-onset periodontitis (EOP). Lymphocytes are the predominant inflammatory/immune cell in EON lesions. B-lymphocytes and plasma cells form the majority subpopulation, and these cells are known to produce antibodies against bacterial antigens. They also may produce autoantibodies, although this has not yet been examined in EON. Antibodies are believed to be primarily beneficial to the host by neutralizing toxins and enhancing phagocytosis of bacteria by PMN. It is presently uncertain what role, if any, NK cells play in EON. There is evidence of abnormal lymphocyte function in EON, particularly in the form of reduced autologous mixed lymphocyte reaction (AMLR).The significance of AMLR reduction is unclear, but it may relate to reduced levels of CD4+, CD45RA+T cells, which in turn may relate to the elevated B-cell response that has been reported in EON.
Analysis of cytokine production in EON lesions suggests that IL-4 levels are enhanced, which may contribute to B-cell proliferation and an elevated local amount of IgG4. Use of molecular techniques to test possible relationships between susceptibility to EON and the lymphocyte response, such as evaluation of MHC Class II and TCR gene usage, promises to provide further clues as to the role of lymphoid cells in, and genetic nature of, these forms of periodontitis. [M.R.]
Engel, D., J Penodont, 67:332,1996