Investigation into toll like receptor mechanisms of action, in relation to Porphyromonas gingivalis in periodontitis

Periodontitis is a chronic inflammatory disease caused by bacterial invasion of the gingival epithelial cells within the oral cavity (Bostanci and Belibasakis, 2012). A key bacterium responsible for this is Porphyromonas gingivalis (P. gingivalis), a gram negative bacterium that evades the host immune system by cell infection. The chronic inflammation shown in periodontitis can cause tissue damage and bone degradation; this can lead to tooth loss (Hajishengallis et al 2011). Within this review P.gingivalis mechanisms of infection are outlined, along with its mediation of the immune system. Recognition by Toll like receptors is also investigated, and the literature on the manipulation of toll like receptors (TLRs) as mediators of inflammation is reviewed. The discovery of macrophage phenotypes and their expression of pro and anti-inflammatory cytokines are outlined, with reference to the potential use of human TLR7 inhibitor imiquimod, as a potential way of reducing inflammation within periodontitis