Titanium Ions Play a Synergistic Role in the Activation of NLRP3 Inflammasome in Jurkat T Cells

Release of titanium ions (Ti ions) frequently occurs around dental implants and, as a consequence, higher content of Ti is typically present in peri-implantitis tissue. Unlike chronic periodontitis, Ti ions may play a role in the development of peri-implantitis. Inflammasomes are multiprotein signal transduction complexes, involved in inflammation and immune response, which lead to the secretion of mature cytokines associated with the progression of peri-implantitis. It is well known that T lymphocytes dominate the immune response in peri-implantitis, but whether Ti ions can impact the assembly of functional inflammasomes in T cells still remains unclear. Here, we observed that the mRNA expression of NLRP3 and CASP1, as well as the secretion of IL-1β, increased after 6-h incubation of Jurkat T cells with PHA and Ti ions. Moreover, measurement by confocal microscopy and flow cytometry assay indicates that Ti ions can promote the production of ROS, while NLRP3 expression and IL-1β secretion are reduced after treatment of Jurkat cells with NAC (ROS scavenger). Taken together, we presently show that Ti ions can activate NLRP3 inflammasome and then promote IL-β secretion in vitro, where ROS may play a mechanistic role in this activation process.