The Role And Effects Of Dendritic Cells'PRRs During The Dental Implant-based Immune Responses

All materials when implanted into living tissue initiate a host response that reflects the first steps of tissue repair. Modern implant design is directed on making use of this immune response to improve implant integration while avoiding its perpetuation leading to chronic inflammation and foreign body reactions, and thus loss of the intended function. Dendritic cells play pivotal roles in responding to foreign entities during an innate immune response and initiating effective adaptive immunity as well as maintaining immune tolerance.This review outlines the current knowledge on immune responses to biomaterials associated with BMDCs. Evidence will be presented that biomaterials mimicking the physiological extracellular matrix(ECM) may have the potential to modulate the immune system by enhancing or suppressing normal immune cell functions through the pattern recognition receptor(PRR) of BMDCs.Dendritic cells(DCs) play pivotal roles in responding to foreign entities during an innate immune response and initiating effective adaptive immunity as well as maintaining immune tolerance. Here, we investigated the role of the cytosolic pattern recognition receptor nucleotide-binding oligomerization domain–containing protein 2(NOD2) Toll-Like Receptor, Noll-Lke Receptor for the Clinical titanium(Ti)substrates–mediated expression and production of cytokines in bone-marrow-derived dendritic cells(BMDCs).Both PT and SLA titanium increased the interleukin-1?(IL-1?), IL-12p35, IL-12p40, interferon-?(IFN-?) and transforming growth factor-?(TGF-?) m RNA expression significantly in unprimed BMDCs. The production of some cytokines were also measured. Both westernblot and Immunofluorescent assay showed that PT induced more NOD2 expression compared with SLA in LPS-priming BMDCs.Moreover, si RNA-mediated downregulation of NOD2 in DC2.4 decreased its cytokines induction and DC maturation-associated markers' expression.In summary, our study provides evidence that Ti substrates activates NOD2 in DCs, resulting in an increased expression of cytokines and DC maturation-associated markers.These data suggest that NOD2 up-regulation is part of the unprimed or LPS-priming BMDCs immune response to Ti substrates and might be important in protecting tissue from the deleterious effects of implantitis...