Characterizing Gingival and Periodontal Ligament Fibroblasts Reaction to Infection With the Bacteria Porphyromonas Gingivalis

Porphyromonas gingivalis is one of the major bacteria involved in the formation and progression of chronic periodontitis. Pathogens invading the gingiva face the host's innate immune system at first and later on the acquired immune system which includes secreted antibodies and specialized cells. Although both the arms of the immune system are coordinated to overcome the infection, there are several known mechanisms which help pathogens as Porphyromonas gingivalis evade immunity. As a result, inflammatory mediators secreted by immune cells cause tissue damage and lead the inflammation process towards chronicity instead of clearing the pathogen. Up till recently most of the studies focused on the role of macrophages, dendritic cells and lymphocytes at the response to periodontal pathogenic bacteria while the role of fibroblasts (the most abundant cell in the connective tissue) was less examined. Fibroblasts are spindle shaped cells which have the ability to produce extra cellular matrix and respond to growth factors and cytokines. They are able to affect cells in the infected tissue and contribute to immune response efficiency. As known in the case of lymphocytes, fibroblasts also vary in subtypes, each differs in phenotype, immune interactions, extra cellular matrix production and destruction, migration abilities and so on. Two main fibroblasts subtypes in the oral cavity originate in the gingival tissue and the periodontal ligament anchoring teeth to the surrounding alveolar bone. Amongst the differences between the two are collagen production ability and receptors profile over the cell surface. Considering all that, the investigators aim to obtain and use periodontal ligament and gingival tissues removed anyways during common dental procedures in order to extract the different fibroblasts subtypes residing there and compare their response to Porphyromonas gingivalis.