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.

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

Uncarinic acid C (URC) is triterpene isolated from Uncaria rhynchophylla and modulates human DC function in a fashion that favors Th1 cell polarization depending on TLR4 signaling. 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. Monocyte-derived DC used as adjuvant cells in cancer immunotherapy and have shown promising results. We studied the effect of interferon's (IFN-α and IFN-γ) and TNF-α on phenotypic and functional maturation, and cytokine production of URC-primed DC in vitro. Human monocytes were exposed to either URC alone, or in combination with TNF-α, IFN-α or IFN-γ, and thereafter co-cultured with naïve T cells. We found that the expression levels of CD1a, CD83 and HLA-DR on URC-primed DC were influenced by IFN-γ and IFN-γ augmented the T cell stimulatory capacity in allo MLR to URC-primed DC. Moreover, the production of IL-12p70 by URC-primed DC was enhanced by IFN-γ. IL-12p70 production by URC-primed DC alone was influenced following treatment with anti-TLR4 mAb, but not DC differentiated with URC plus IFN-γ. URC plus IFN-γ-primed DC induced a substantial increase in the secretion of IFN-γ by T cells, which is dependent on IL-12 secretion. DC maturated with URC plus IFN-γ had an intermediate migratory capacity towards CCL19 and CCL21. In addition, the expression levels of CCR7 on URC-primed DC were enhanced by IFN-γ. In contrast, surface molecule up-regulation and function of URC-primed DC were slightly enhanced by TNF-α, and IFN-α. These results suggest that the enhancement of Th1 cells polarization to URC-primed DC induced by IFN-γ depends on the activation of IL-12p70 and independent on TLR4. DC differentiated with URC in combination with IFN-γ might 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.

All-trans retinoic acid inhibits the differentiation, maturation, and function of human monocyte-derived dendritic cells.

All-trans retinoic acid (ATRA) affects on the function of antigen presenting cells with somewhat controversies. We investigated the effects of ATRA on differentiation, maturation and function of human monocyte-derived dendritic cells (DCs). Low dose (10(-14)M) or high dose (10(-6)M) of ATRA was added either when monocytes were differentiated into immature DCs (imDCs) or mature DCs (mDCs) were induced. Apoptotic cell populations were dramatically increased in imDCs or mDCs with increasing concentration of ATRA. The productions of IL-12p40 and IL-12p70 were significantly suppressed in imDCs or mDCs induced by the addition of ATRA in the dose-dependent manner, whereas IL-10 was increased. DCs cultured with ATRA induced the differentiation of naïve T cells towards a helper T cell type 2 (Th2) response and expansion of CD4(+)CD25(+)Foxp3(+) regulatory T cells. Allostimulatory capacity of DCs was suppressed with increasing concentration of ATRA. These findings suggest that ATRA inhibits the effects on the differentiation, maturation and function of human monocyte-derived DCs in vitro and also enhance the differentiation of naïve T cell toward the Th2 type.

Detection of levorotatory methamphetamine and levorotatory amphetamine in urine after ingestion of an overdose of selegiline.

In this study, we measured the urine concentrations of methamphetamine and amphetamine as metabolites of selegiline after ingestion of an overdose of selegiline. A patient who had developed Parkinson disease took selegiline in a suicide attempt. Analysis by gas chromatography-mass spectrometry (GC-MS) with trifluoroacetic acid-derivatization revealed the presence of methamphetamine and amphetamine in the patient's urine at concentrations of 0.62 microg/ml and 0.25 microg/ml, respectively. To determine the stereospecificity of the methamphetamine and amphetamine, a urine sample was analyzed by GC-MS after derivatization with N-(trifluoroacetyl)-l-prolyl chloride. The methamphetamine and amphetamine were levorotatory in form. The ratio of the methamphetamine to amphetamine concentration in the urine was 2.5. This value is consistent with other case reports of ingestion of selegiline, which suggests that the methamphetamine to amphetamine concentration ratio in urine is useful information for indicating use of selegiline.

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.

Dendritic Cells Promoted by Ginseng Saponins Drive a Potent Th1 Polarization.

Dendritic cells (DC) play a pivotal role in the initiation of T-cell-mediated immune responses, making them an attractive cellular adjuvant for use in cancer vaccines. The interaction of T cells with DC is crucial for directing T cell differentiation towards the Th1, Th2 or Th17 type, and several factors determining the direction of the T cell polarization. IL-12 plays a central role in the immune system, not only by augmenting the cytotoxic activity of T cells and NK cells and regulating IFN-gamma production, but also by the capacity of IL-12 to promote the development of Th1 cells. Therefore, it is important to identify factors that might affect the differentiation, maturation and function of DC. Ginseng is a medicinal herb widely used in Asian countries, and many of its pharmacological actions are attributed to the ginsenosides. Moreover, T-cadinol and calamenene are sesquterpenes isolated from the heartwood of Cryptomeria japonica being pharmacologically active substances. We investigated whether M1 and M4, end products of steroidal ginseng saponins metabolized in digestive tracts, as well as T-cadinol and calamenene can drive DC maturation from human monocytes in vitro. Human monocytes were cultured with GM-CSF and IL-4 for 6 days under standard conditions, followed by another 2 days in the presence of M1, M4, T-cadinol or calamenene. The expression levels of CD1a, CD80, CD83, CD86 and HLA-DR on M1-primed DC, M4-primed DC, T-cadinol-primed DC and calamenene-primed DC were enhanced with a concomitant decrease in endocytic activity. M1-primed DC, M4-primed DC, T-cadinol-primed DC or calamenene-primed DC enhanced the T cell stimulatory capacity in an allo MLR (allogeneic mixed lymphocyte reaction). Naïve T cells co-cultured with allogeneic M1-primed DC, M4-primed DC, T-cadinol-primed DC or calamenene-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. In the CTL assay (cytotoxic T-lymphocyte assay), the production of IFN-gamma and (51)Cr release on M4-primed DC was more augmented than of immature DC or TNF-alpha-primed DC. These results suggest that M1, M4, T-cadinol and calamenene appear to be a good factor to induce DC maturation, or even better in some respect, for the use in clinical DC therapy to induce strong Th1 type immune responses.

Diterpenes inhibit IL-12 production by DC and enhance Th2 cells polarization.

Sugiol and 12-hydroxy-6,7-secoabieta-8,11,13-triene-6,7-dial (Secoferruginol) are diterpenes isolated from the heartwood of Cryptomeria japonica and are pharmacologically active substances. Dendritic cells (DC) have a key influence on the differentiation of naïve T cells into Th1 or Th2 effector cells. We demonstrate that Sugiol and Secoferruginol activate human DC as documented by phenotypic and functional maturation and altered cytokine production. Human monocytes were exposed to Sugiol or Secoferruginol alone, or in combination with LPS and thereafter co-cultured with naïve T cells. The expression levels of CD83 on Sugiol-primed DC were enhanced. Sugiol dose-dependently inhibited IL-12p70 production by LPS-primed DC and to a lesser extent, the production of the proinflammatory cytokines. Naïve T cells co-cultured with Sugiol-primed DC, turned into typical Th2 which produced large quantities of IL-4 and released small amounts of IFN-gamma and reduced Th1 cell polarizing capacity. Sugiol-primed DC induced the development of Th2 cells via the enhanced expression of OX40L and augmented the Th2 cell polarizing capacity of DC via the inhibition of IL-12p70. Similar results were obtained with Secoferruginol. These results suggest that some diterpenes modulate human DC function in a fashion that favors Th2 cell polarization and might have implication in autoimmune diseases.

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

T-cadinol and calamenene are sesquiterpenes isolated from the heartwood of Cryptomeria japonica and are pharmacologically active substances. Dendritic cells are pivotal in the initiation of adaptive immune responses and are recognized as key to the induction of immune responses to cancer. This study investigated the effects of T-cadinol and calamenene on the phenotypic and functional maturation of human monocyte-derived dendritic cells in vitro. Human monocytes were cultured with recombinant human granulocyte-macrophage colony-stimulation factor (GM-CSF) and recombinant human interleukin-4 (IL-4) for 6 days under standard conditions, followed by another 2 days in the presence of T-cadinol, calamenene, lipopolysaccharide (LPS), CT or nifedipine. Dendritic cells harvested on day 8 were examined using functional assays. The expression levels of CD1a, CD80, CD83, CD86 and HLA-DR on T-cadinol-primed dendritic cells or calamenene-primed dendritic cells were enhanced with a concomitant decrease in endocytic activity. T-cadinol-primed dendritic cells or calamenene-primed dendritic cells also enhanced the T cell stimulatory capacity in an allogeneic mixed lymphocyte reaction, as measured by T cell proliferation. Naïve T cells co-cultured with allogeneic T-cadinol-primed dendritic cells or calamenene-primed dendritic cells at 1:5 dendritic cells/T cell ratio turned into typical Th1 cells which produced large quantities of interferon-gamma (IFN-gamma) and released small amounts of IL-4 depending on IL-12 secretion. In contrast, naïve T cells co-cultured with CT-primed dendritic cells turned into Th2 cells. T-cadinol-primed dendritic cells and calamenene-primed dendritic cells expressed the chemokine receptor CCR7 and had a high migration to macrophage inflammatory protein (MIP-3beta). Intracellular Ca(2+) mobilization in T-cadinol-primed dendritic cells and calamenene-primed dendritic cells was induced by MIP-3beta. The differentiation and functional maturation of human monocyte-derived dendritic cells were not affected by nifedipine. These results suggest that T-cadinol and calamenene may be used in dendritic cells-based immunotherapy for cancer.

A sea urchin lectin, SUL-1, from the Toxopneustid sea urchin induces DC maturation from human monocyte and drives Th1 polarization in vitro.

The sea urchin Toxopneustes pileolus belonging to the family Toxopneustidae, they have well-developed globiferous pedicellariae with pharmacologically active substances. We have purified a novel sea urchin lectin-1 (SUL-1) from the large globiferous pedicellariae of T. pileolus. Dendritic cells (DC) are professional APC and play a pivotal role in controlling immune responses. This study investigated whether SUL-1 can drive DC maturation from human immature monocyte-derived DC in vitro. Human monocytes were cultured with GM-CSF and IL-4 for 6 days followed by another 1 day in the presence of SUL-1 or LPS. DC harvested on day 7 were examined using functional assays. The expression levels of CD1a, CD80, CD83, CD86 and HLA-DR as expressed by mean fluorescence intensity (MFI) on DC differentiated from immature DC after culture with 1.0 microg/ml of SUL-1 for 1 day were enhanced and decreased endocytic activity. SUL-1-treated DC also displayed enhanced T cell stimulatory capacity in an MLR, as measured by T cell proliferation. Cell surface expression of CD80, CD83 and CD86 on SUL-1-treated DC was inhibited by anti-DC-SIGN mAb, while anti-DC-SIGN mAb had no influence on allogeneic T cell proliferation by SUL-1-treated DC. DC differentiated with SUL-1 induced the differentiation of naïve T cell towards a helper T cell type 1 (Th1) response at DC/T (1:5) cells ratio depending on IL-12 secretion. In CTL assay, the production of IFN-gamma and 51Cr release on SUL-1-treated DC were more augmented than of immature DC or LPS-treated DC. SUL-1-treated DC expressed CCR7 and had a high migration to MIP-3beta. Intracellular Ca2+ mobilization in SUL-1-treated DC was also induced by MIP-3beta. These results suggest that SUL-1 bindings to DC-SIGN on surface of immature DC may lead to differentiate DC from immature DC. Moreover, it suggests that SUL-1 may be used on DC-based vaccines for cancer immunotherapy.

Epicubenol and Ferruginol induce DC from human monocytes and differentiate IL-10-producing regulatory T cells in vitro.

Epicubenol and 19-hydroxyferruginol (Ferruginol) are sesquiterpenes isolated from the black heartwood of Cryptomeria japonica. Dendritic cells (DC) are specialized antigen-presenting cells that monitor the antigenic environment and activate naïve T cells. The role of DC is not only to sense danger but also to tolerize the immune system to antigens encountered in the absence of maturation/inflammatory stimuli. In this study, we attempted to investigate the effects of Epicubenol and Ferruginol on the phenotypic and functional maturation of human monocytes-derived DC in vitro. Human monocytes were cultured with GM-CSF and IL-4 for 6 days under standard conditions, followed by another 2 days with Epicubenol or Ferruginol. The expression levels of CD1a, CD83, and HLA-DR as expressed by mean fluorescence intensity (MFI) on Epicubenol-primed DC or Ferruginol-primed DC were enhanced. Allogeneic Epicubenol-primed DC or Ferruginol-primed DC co-cultured with naïve T cells at 1:5 ratio, secreted IL-10 and TGF-beta, but little IL-4. Moreover, T cells that develop in co-culture of Epicubenol-primed DC or Ferruginol-primed DC and naïve T cells at 1:5 ratio suppressed the proliferation of autologous T cells at Treg cells: Ttarget cells and this suppression of proliferation was inhibited by anti-IL-10 mAb. The expression of FoxP3 mRNA on T cells that develop in co-culture of Epicubenol-primed DC or Ferruginol-primed DC and naïve T cells was lower. From these results, Epicubenol and Ferruginol may induce IL-10-producing Treg 1 cells from naïve T cells by modulating DC function. It seems that Epicubenol and Ferruginol appear to be a target for tolerance after transplantation and in autoimmune diseases.

Expansion of alpha-galactosylceramide-stimulated Valpha24+ NKT cells cultured in the absence of animal materials.

Valpha24+ NKT is an innate lymphocyte with potential antitumor activity. Clinical applications of Valpha24+ natural killer (NK) T cells, which are innate lymphocytes with potential antitumor activity, require their in vitro expansion. To avoid the potential dangers posed to patients by fetal bovine serum (FBS), the authors evaluated non-FBS culture conditions for the selective and efficient expansion of human Valpha24+ NKT cells. Mononuclear cells (MNCs) and plasma from the peripheral blood of normal healthy donors were used before and after G-CSF mobilization. MNCs and plasma separated from apheresis products were also used. MNCs were cultured for 12 days in AIM-V medium containing alpha-galactosylceramide (alpha-GalCer) (100 ng/mL) and IL-2 (100 U/mL) supplemented with FBS, autologous plasma, or autologous serum. The cultured cells were collected and their surface markers, intracellular cytokines, and cytotoxicity were evaluated. The highest expansion ratio for Valpha24+ NKT cells was obtained from G-CSF-mobilized MNCs cultured in medium containing 5% autologous plasma. Cultures containing MNCs and autologous plasma obtained before and after G-CSF mobilization had approximately 350-fold and 2,000-fold expansion ratios, respectively. These results suggest that G-CSF mobilization conferred a proliferative advantage to Valpha24+ NKT cells by modifying the biology of cells and plasma factors. Expanded Valpha24+ NKT cells retained their surface antigen expression and production of IFN-gamma and exhibited CD1d-independent cytotoxicity against tumor cells. Valpha24+ NKT cells can be efficiently expanded from G-CSF-mobilized peripheral blood MNCs in non-FBS culture conditions with alpha-GalCer and IL-2.

Effect of piceatannol in human monocyte-derived dendritic cells in vitro.

Piceatannol is an anti-inflammatory, immunomodulatory, and antiproliferative stilbene that has been shown to interfere with the cytokine signaling pathway. Dendritic cells (DCs) play a pivotal in the initiation of T-cell-mediated immune responses, making them an attractive cellular adjuvant for use in cancer vaccines. This study investigated the effect of piceatannol on the phenotypic and functional maturation of human monocyte-derived DCs in vitro. Human monocytes were cultured with GM-CSF and IL-4 for 6 days, followed by another 2 days in the presence of piceatannol or LPS. DCs harvested on day 8 were examined using functional assays. The expression levels of CD1a, CD80, CD83, and CD86 as expressed by mean fluorescence intensity (MFI) on DCs differentiated from immature DCs after culture with 1 muM of piceatannol for 2 days were enhanced and decreased endocytic activity. Piceatannol-treated DCs also displayed enhanced T-cell stimulatory capacity in a MLR, as measured by T-cell proliferation. Similar results were obtained with DCs differentiated with LPS from immature DCs. However, piceatannol did not inhibit phenotypic and functional maturation induced by LPS from immature DCs. Piceatannol-treated DCs induced the differentiation of naive T cells towards a helper T-cell type 1 (Th1) response at DCs/T (1:5) cells ratio depending on IL-12 secretion. These results demonstrate that piceatannol may be used on DC-based vaccine for cancer immunotherapy.

Dendritic cells maturation promoted by M1 and M4, end products of steroidal ginseng saponins metabolized in digestive tracts, drive a potent Th1 polarization.

Ginseng is a medicinal herb widely used in Asian countries, and many of its pharmacological actions are attributed to the ginsenosides. Dendritic cells (DCs) play a pivotal in the initiation of T-cell-mediated immune responses, making them an attractive cellular adjuvant for use in cancer vaccines. In this study, we investigated whether M1 and M4, end products of steroidal ginseng saponins metabolized in digestive tracts, can drive DCs maturation from human monocytes in vitro. Human monocytes were cultured with GM-CSF and IL-4 for 6 days, followed by another 2 days in the presence of M1, M4 or TNF-alpha as a maturation stimulus. Stimulation with 20 microM of M1 or M4 increased expression level of CD80, CD83 and CD86 as expressed by mean fluorescence intensity (MFI) and decreased endocytic activity. M4-primed mature DCs also displayed enhanced T cells stimulatory capacity in a MLR, as measured by T cell proliferation. Mature DCs differentiated with M1 or M4 induced the differentiation of naïve T cells towards a helper T cell type 1 (Th1) response at DC/T (1:5) cells ratio depending on IL-12 secretion. In CTL assay, the production of IFN-gamma and 51Cr release on M4-primed mature DCs was more augmented than of immature DCs or TNF-alpha-primed mature DCs. These results suggest that M4 may be used on DC-based vaccines for cancer immunotherapy.