[Immune response and dentobacterial plaque]

The effects of bacterial plaque on the immunologic response are varied and complex, which is astounding considering the nature of the plaque. The large number of gram-positive and gram-negative bacteria and their products like lipopolysaccharides (LPS), lipoteicoic acids (LTA), dextrans and levanes, permit the activation of most immunologic mechanisms. Both the classical and alternate paths in the complement system are activated, as well as lymphocytes, macrophages, and lymphocyne liberation. Polyclonal mitogens evolving to B lymphocytes may perform an important function in lymphocyte stimulation. An immunogenetic control over the functions of T auxiliary cells has been suggested, with at least one antigen from plaque, and related to the HLA-DR. These reactions may be modulated through potentiating and suppressing effects of some plaque components, thus resulting in a chronic localized inflammatory response.