Ursolic acid isolated from Uncaria rhynchophylla activates human dendritic cells via TLR2 and/or TLR4 and induces the production of IFN-gamma by CD4+ naïve T cells.

Ursolic acid is triterpene isolated from Uncaria rhynchophylla and is a pharmacologically active substance. The induction of dendritic cell maturation is critical for the induction of Ag-specific T-lymphocyte response and may be essential for the development of human vaccine relying on T cell immunity. In this study, we investigated that the effect of Ursolic acid on the phenotypic and functional maturation of human monocyte-derived dendritic cells in vitro. Dendritic cells harvested on day 8 were examined using functional assay. The expression levels of CD1a, CD80, CD83, CD86, HLA-DR and CCR7 on Ursolic acid-primed dendritic cells was slightly enhanced. Ursolic acid dose-dependently enhanced the T cell stimulatory capacity in an allogeneic mixed lymphocyte reaction, as measured by T cell proliferation. The production of IL-12p70 induced by Ursolic acid-primed dendritic cells was inhibited by the anti-Toll-like receptor-2 (TLR2) mAb and anti-TLR4 mAb. Moreover, Ursolic acid-primed dendritic cells expressed levels of mRNA coding for both TLR2 and TLR4. The majority of cells produced considerable interferon-gamma (IFN-gamma), but also small amounts of interleukin (IL-4)-4. Ursolic acid-primed dendritic cells have an intermediate migratory capacity towards CCL19 and CCL21. These results suggest that Ursolic acid modulates human dendritic cells function in a fashion that favors Th1 polarization via the activation of IL-12p70 dependent on TLR2 and/or TLR4, and may be used on dendritic cells-based vaccines for cancer immunotherapy.

Jung TY ，Pham TN ，Umeyama A ，Shoji N ，Hashimoto T ，Lee JJ ，Takei M ... -  《-》

Uncarinic acid C plus IFN-γ generates monocyte-derived dendritic cells and induces a potent Th1 polarization with capacity to migrate.

Bae WK ，Umeyama A ，Chung IJ ，Lee JJ ，Takei M ... -  《-》

T-cadinol and calamenene induce dendritic cells from human monocytes and drive Th1 polarization.

Takei M ，Umeyama A ，Arihara S 《EUROPEAN JOURNAL OF PHARMACOLOGY》

Cryptomerione induces Th1 cell polarization via influencing IL-10 production by cholera toxin-primed dendritic cells.

Takei M ，Umeyama A ，Lee JJ ，Shoji N ，Hashimoto T ... -  《-》

Polyacetylenediols regulate the function of human monocyte-derived dendritic cells.

Callyspongidiol and 14,15-dihydrosiphonodiol are Polyacetylenediols isolated from marine sponges and are pharmacologically active substances. Dendritic cells (DC) play an important role in the initiation and regulation of immune response. DC have a key influence in the differentiation of naïve T cells into Th1, Th2 or Th17 effector cells. We demonstrated that callyspongidiol and 14,15-dihydrosiphonodiol activate human DC as documented by phenotypic and functional maturation, and altered cytokine production. Up regulation of cell surface expression of CD1a, CD80, CD83, CD86, HLA-DR and CCR7 was observed following DC treatment with callyspongidiol and 14,15-dihydrosiphonodiol. The production of IL-10 by callyspongidiol-primed DC after stimulation with CD40-L was higher than that of LPS- or 14,15-dihydrosiphonodiol-primed DC. Naïve T cells co-cultured with allogeneic 14,15-dihydrosiphonodiol-primed DC at 1:5 DC/T cell ratio turned into typical Th1 cells depending on IL-12 secretion and independent on TLR2 or TLR4. In contrast, callyspongidiol-primed DC co-cultured with naïve T cells secreted IL-4 and IL-10, but had little effect on IFN-gamma. Callyspongidiol-primed DC induced the development of Th2 cells via the inhibition of IL-12p70 and the enhancement of IL-10. Polyacetylenediols-primed DC expressed the chemokine receptor CCR7 and had a high migration to CCL19. These results suggested that some Polyacetylenediols modulate human DC function in a fashion that favors Th1/Th2 cell polarization or IL-10 producing T cells, and might have implication in tumor or in autoimmune diseases.

Takei M ，Umeyama A ，Shoji N ，Hashimoto T ... -  《-》