Quantitative analysis of macrophages in gingivitis and periodontal disease

Periodontal disease is a chronic inflammatory disease, the pathogenesis of which involves different innate immune system as well as adaptive immune system cells, including macrophages. Macrophages are professional phagocytes whose primary role is ingestion and destruction of microorganisms. Apart from phagocytosis, these cells are engaged in production of proinflammatory cytokines and antigen presentation to T cells, and therefore are considered to be the key cells of the innate immune response. Our study focused on distribution and density of macrophages in healthy and inflamed gingiva with the purpose of evaluating their relevance to pathogenesis of periodontal disease. The material used for this purpose were gingival biopsies taken from 96 patients assorted in 4 groups: the healthy gingiva, gingivitis, moderate periodontal disease and severe periodontal disease. The immunohistochemical staining method based on the use of monoclonal antibodies anti-CD68 was used for identification of macrophages. Our study showed that the density of macrophages is higher in gingivitis and periodontal disease compared to healthy gigiva. There were no significant differences found regarding the density of macrophages in gingivitis and periodontal disease. Grouping of macrophage populations close to partially lysed collagen fibers in periodontal disease indicates their collagenic activity. The increase in the number of macrophages in inflamed gingival tissue could be linked to bone resorption due to the fact that these cells are capable of differentiating into osteoclasts.