Uncarinic Acid C Isolated from Uncaria rhynchophylla Induces Differentiation of Th1-Promoting Dendritic Cells Through TLR4 Signaling.

Uncarinic acid C (URC) is triterpene isolated from Uncaria rhynchophylla and is a pharmacologically active substance. The induction of dendritic cells (DC) is critical for the induction of Ag-specific T lymphocyte responses and may be essential for the development of human vaccines relying on T cell immunity. DC might be a potential target for URC. We demonstrate that URC activates human DC as documented by phenotypic and functional maturation, and altered cytokine production. The expression of CD1a, CD38, CD40, CD54, CD80, CD83, CD86, HLA-DR and CCR7 on URC-primed DC was enhanced. The production of IL-12p70 by URC-primed DC was higher than that of lipopolysaccharide (LPS)-primed DC. The production of IL-12p70 by URC-primed DC was inhibited by the anti-Toll-like receptor 4 (TLR4) monoclonal antibody (mAb), but partially abolished by anti-TLR2 mAb. mRNA coding for TLR2 and TLR4 was expressed in URC-primed DC. URC-primed DC induced the NF-κB transcription factor. Naïve T cells co-cultured with URC-primed DC turned into typical Th1 cells that produced large quantities of IFN-γ depending on IL-12 secretion. URC enhanced the T cell stimulatory capacity in an allo MLR. In the cytotoxic T-lymphocyte assay (CTL) assay, DNA fragmentation assay and (51)Cr release on URC-primed DC were more augmented than that of TNF-α-primed DC. DC matured with URC had an intermediate migratory capacity towards CCL19 and CCL21. These results suggest that URC modulates DC function in a fashion that favors Th1 polarization via the activation of IL-12p70 dependent on TLR4 signaling, and may be used on DC-based vaccine for cancer immunotherapy.

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.

Triterpene esters from Uncaria rhynchophylla drive potent IL-12-dependent Th1 polarization.

Dendritic cells (DC) are key antigen-presenting cells that link innate and adaptive immunity and ultimately activate antigen-specific T cells. In the current study, we demonstrated that two triterpene esters, uncarinic acid C (1) and uncarinic acid D (2), which are isolated from the hooks of Uncaria rhynchophylla, activate phenotypic and cytokine production alterations in DC. We also show that 1 and 2 modulate human DC function in a fashion that favors Th1 cell polarization. The effect of 1 (E configuration at the 2' position) was approximately 20 times more potent than that of 2 (Z configuration at 2'). These results indicated that the configuration of the 2' double bond greatly effects activity. Thus, 1 and 2 may prove useful as DC-based vaccines for cancer immunotherapy.

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.

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

Dendritic cells play an important role in the initiation and regulation of immune response. Dendritic cells have a key influence in the differentiation of naïve T cells into Th1, Th2 or Th17 effector cells. Cryptomerione is terpene isolated from the heartwood of Cryptomeria japonica. In this study, we investigated the effects of Cryptomerione on the phenotypic and functional maturation of human monocyte-derived dendritic cells in vitro. Human monocytes were exposed to either Cryptomerione alone, or in combination with lipopolysaccaride (LPS) or cholera toxin (CT) and thereafter co-cultured with naïve T cells. We found no enhanced CD1a, CD80, CD83, CD86 and HLA-DR expression on Cryptomerione-primed dendritic cells. However, Cryptomerione augmented T cell stimulatory capacity in an allogeneic mixed lymphocyte reaction to CT-primed dendritic cells and influenced the production of interleukin (IL)-10 and IL-12p70 by CT-primed dendritic cells, but not LPS-primed dendritic cells. Cryptomerione also inhibited Th2 cell polarization induced by CT-primed dendritic cells, but enhanced IFN-gamma secretion by naïve T cells co-cultured with CT-primed dendritic cells. Cytokine production by CT-primed dendritic cells alone, or in combination with Cryptomerione was also influenced following treatment with anti-IL-10 mAb and anti-OX40L mAb. Thus, the potential mechanisms underlying the enhancement of Th1 polarization in CT-primed dendritic cells induced by Cryptomerione appeared to depend on IL-10 secretion and OX40L. These results suggest that Cryptomerione modulates human dendritic cells function in a fashion that favors Th1/Th2 cell polarization.

Polyacetylene diols with antiproliferative and driving Th1 polarization effects from the marine sponge Callyspongia sp.

A screening of 30 crude extracts of marine sponges against human promyelocytic leukemia cells (HL-60) yielded an EtOAc extract of the sponge Callyspongia sp. (Callyspongiidae) with significant activity. Further bioassay-guided fractionation of the EtOAc extract led to the isolation of three polyacetylene metabolites: a new polyacetylene diol, callyspongidiol (1), along with two known compounds, siphonodiol (2) and 14,15-dihydrosiphonodiol (3). Their structures were determined by a combination of spectroscopic analyses. Compounds 1-3 exhibited antiproliferative activity against HL-60 with IC(50) values of 6.5, 2.8, and 6.5 microg/ml, respectively. These metabolites induce apoptosis in HL-60 cells. Dendritic cells (DC) differentiated with 1-3 enhance the differentiation of naïve T cells towards the Th1 type.

Diterpenes drive Th1 polarization depending on IL-12.

Sandaracopimaric acid and Sandaracopimaradiene-3beta-ol are diterpenes isolated from the heatwood of Cryptomeria japonica and are pharmacologically active substances. Dendritic cells (DC) are key antigen presenting cells (APC), which link innate and adaptive immunity, ultimately activating antigen-specific T cells. We demonstrate that Sandaracopimaric acid and Sandaracopimaradiene-3beta-ol activate humans DC as documented by phenotypic and functional maturation and altered cytokine production. The expression of the co-stimulatory molecules such as CD83, CD86 and HLA-DR on Sandaracopimaric acid- and Sandaracopimaradiene-3beta-ol-primed DC was enhanced. Sandaracopimaric acid- and Sandaracopimaradiene-3beta-ol-primed DC also enhanced the T cell stimulatory capacity in an allo MLR. Naive T cells co-cultured with Sandaracopimaric acid- or Sandaracopimaradiene-3beta-ol-primed DC turned into typical Th1 cells, which produced large quantities of IFN-gamma and released small amounts of IL-4 depending on IL-12 secretion. Sandaracopimaric acid- or Sandaracopimaradiene-3beta-ol-primed DC had a high migration to macrophage inflammatory protein (MIP)-3beta. These results suggest that some diterpenes modulate human DC function in a fashion that favors Th1 cell polarization and may be used on DC-based vaccines for cancer immunotherapy.

Differential regulation of DC function by Siphonodiol.

Siphonodiol is a polyacetylene diol isolated from marine sponges Callyspongia sp. We demonstrate that the effect of Siphonodiol on the phenotypic and functional maturation of human monocyte derived DC in vitro. Human monocytes were exposed to Siphonodiol alone, or in combination with LPS and thereafter co-cultured with naïve T cells. The expression levels of CD1a, CD80, CD83, CD86 and HLA-DR on LPS-primed DC were partially enhanced by Siphonodiol. Siphonodiol augmented the T cell stimulatory capacity in an allo MLR to LPS-primed DC. Siphonodiol dose-dependently enhanced the production of IL-12p70 by LPS-primed DC and this cytokine production was inhibited by anti-TLR4 mAb. IFN-gamma secretion from naive T cells co-cultured with DC differentiated with LPS was augmented by Siphonodiol. These results suggest that the enhancement of Th1 cells polarization to LPS-primed DC induced by Siphonodiol depends on TLR4 and via the activation of IL-12p70.

Diterpene, 16-phyllocladanol enhances Th1 polarization induced by LPS-primed DC, but not TNF-alpha-primed DC.

16-Phyllocladanol is diterpene isolated form the heartwood of Cryptomeria japonica. We demonstrate that the effect of 16-phyllocladanol on the phenotypic and functional maturation of human monocytes-derived DC in vitro. Human monocytes were exposed to 16-phyllocladanol alone, or in combination with LPS and thereafter co-cultured with naïve T cells. The expression levels of CD83 and HLA-DR on LPS-primed DC were enhanced by 16-phyllocladanol. 16-Phyllocladanol dose-dependently augmented the T cell stimulatory capacity in an allo MLR to LPS-primed DC and the production of IL-12p70 by LPS-primed DC. The cytokine production by 16-phyllocladanol-primed DC was not inhibited by anti-TLR2 and 4 mAbs. IFN-gamma secretion from naïve T cells co-cultured with DC differentiated with LPS was also augmented by 16-phyllocladanol. These results suggest that the enhancement of Th1 cells polarization to LPS-primed DC induced by 16-phyllocladanol via the activation of IL-12p70 and independent on TLR2 or TLR4.