While gold-silver-palladium alloy is widely used in dental treatment such as treatment of silver teeth as a dental metal material in insurance medical treatment, there is a problem that palladium contributes to cause metal allergy.Palladium dissolved by acid foods, decomposition of foods left in the mouth, and metabolites of oral bacteria has some influence on antigen presentation, and it is thought that activation of T cells causes metal allergy. The mechanism of T cell activation by metal was unknown.

　In this study, when a palladium solution is added to a dendritic cell line, which is one of the antigen-presenting cells, MHC (major histocompatibility complex) class I, which triggers an immune reaction, is temporarily taken up into the cells, and then It was found that it reappears on the cell surface.At this time, it was found that the antigenic peptide presented on MHC class I was replaced with the internalization of cells and became an allergic antigen.Allergic antigens expressed by antigen-peptide substitution are thought to induce T cell activation and lead to the development of palladium allergy.

　From this finding, it was also found that inhibition of palladium-induced MHC class I internalization can suppress T cell activation.Preventing the replacement of antigenic peptides and identifying the antigenic peptides that cause allergies are also expected to lead to the development of new preventive and therapeutic methods for dental metal allergies.

Paper information:[Frontiers in Immunology] Palladium-induced temporal internalization of MHC Class I contributes to T cell-mediated antigenicity