Immunomodulatory effects of piperine on dendritic cell function (50.36)

Abstract

Abstract Piperine is a major alkaloid in black and long pepper and has been shown to have potent anti-inflammatory properties. In this study we investigated the immunomodulatory effects of piperine on dendritic cells (DC), key initiators and modulators of T cell mediated immune responses. C57BL/6 bone marrow derived DC were matured in the presence of 100 µM of piperine or vehicle control. DC maturation marker and chemokine receptor expression was assessed by flow cytometry. T cell proliferation was measured by CFSE dilution. Cytokine secretion was assessed by cytometric bead array assay. In vitro DC migration was assessed using CCL21 as the chemotactic stimulus. Piperine treated DC showed decreased expression of CD40, CD86, class II MHC and CCR7 and increased expression of CCR5, consistent with an immature phenotype. DC production of IL-6, TNF and MCP-1 was significantly reduced following piperine treatment. Treatment with piperine also reduced DC migration and DC induced T cell proliferation. In addition, naïve T cells activated with piperine-treated DC secreted lower levels IFN-γ, IL-4, IL-17, and IL-2. This study demonstrates that piperine inhibits DC maturation, migration and T cell stimulatory capacity. Further investigation of piperine mediated DC immunomodulation could lead to the development of novel therapies for the treatment of autoimmune disorders or allograft rejection. This research is supported by CIHR.