Lepista sordida Water Extract Enhances the Maturation of Mouse Dendritic Cells in Vitro and in Vivo

Background: Lepista sordida (LS) extract has been shown to possess anti-oxidant, anti-aging, and anti-tumor activities. However, the immunostimulatory effect of LS extract has not been elucidated. Objective: To characterize the impact of a water extract of LS (WE-LS) on the maturation and function of mouse dendritic cell (DC) in vitro and in vivo. Methods: Mouse bone marrow-derived DCs (BMDCs) were generated. Next, DC maturation was determined by flow cytometry, and cytokine production was measured by ELISA after WE-LS treatment. In addition, DC-induced OVA-specific T cell activation was assayed by [3H]-thymidine incorporation assay. Furthermore, the in vivo effects of WE-LS on DC maturation and Th1 responses in the spleens of mice were assessed by flow cytometry. Results: WE-LS treatment up-regulated co-stimulatory (CD40 and CD80) and MHC class II molecules, increased the production of tumor necrosis factor-alpha (TNF-α), IL-6 and IL-12, and enhanced both the proliferation and IFN-γ secretion of allogenic T cells in BMDCs, partially mediated by the TLR2 and TLR4 signaling pathways. Moreover, the in vivo administration of WE-LS to mice enhanced the up-regulation of CD40, CD80 and MHC class II molecules in spleen DCs. WE-LS also increased the generation of T helper type 1 (Th1) cells in vivo. Conclusion: These results suggest that WE-LS might have the potential to promote immunity against infection and cancer or to serve as an adjuvant in vaccines and immunotherapies.