Polarization Profiles of T Lymphocytes and Macrophages Responses in Periodontitis.

Periodontitis is a multifactorial, chronic inflammatory disease affecting the supporting structures of teeth triggered by the complex interactions between a dysbiotic bacterial biofilm and the host's immune response that results in the characteristic loss of periodontal attachment and alveolar bone. The differential phenotypic presentations of periodontitis emerge from inter-individual differences in immune response regulatory mechanisms. The monocyte-macrophage system has a crucial role in innate immunity and the initiation of the T and B lymphocyte adaptive immune responses. Macrophages involve a heterogeneous cell population that shows wide plasticity and differentiation dynamics. In response to the inflammatory milieu, they can skew at the time of TLR ligation to predominant M1 -pro-inflammatory- or M2 -anti-inflammatory/healing- functional phenotypes. The perpetuation of inflammation by M1 macrophages leads to the recruitment of the adaptive immune response, promoting Th1, Th17, and Th22 differentiation, which are directly associated with periodontal breakdown. In contrast, M2 macrophages induce Th2 and Treg responses which are associated with periodontal homeostasis. In this article, we review the recent advances comprising the role of macrophages and lymphocyte polarization profiles and their reprogramming as potential therapeutic strategies. For this purpose, we reviewed the available literature targeting periodontitis, macrophage, and lymphocyte subpopulations with an emphasis in the later 5 years. The active reprogramming of macrophages and lymphocytes polarization crosstalk opens a promising area for therapeutic development.