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Effective activation of dendritic cells (DCs) toward T helper (Th)-1 cell polarization would improve DC-based antitumor immunotherapy, helping promote the development of immunotherapeutic vaccines based on T-cell immunity. To achieve this goal, it is essential to develop effective immune adjuvants that can induce powerful Th1 cell immune responses. The pathogenic organism Mycobacterium tuberculosis includes certain constitutes, such as heparin-binding hemagglutinin (HBHA), that possess a strong immunostimulatory potential. In this study, we report the first clarification of the functions and precise mechanism of HBHA in immune stimulation settings relevant to cancer. HBHA induced DC maturation in a TLR4-dependent manner, elevating expression of the surface molecules CD40, CD80, and CD86, MHC classes I and II and the proinflammatory cytokines IL-6, IL-12, IL-1β, TNF-α, and CCR7, as well as stimulating the migratory capacity of DCs in vitro and in vivo. Mechanistic investigations established that MyD88 and TRIF signaling pathways downstream of TLR4 mediated secretion of HBHA-induced proinflammatory cytokines. HBHA-treated DCs activated naïve T cells, polarized CD4+ and CD8+ T cells to secrete IFN-γ, and induced T-cell–mediated cytotoxicity. Notably, systemic administration of DCs that were HBHA-treated and OVA251–264-pulsed ex vivo greatly strengthened immune priming in vivo, inducing a dramatic regression of tumor growth associated with long-term survival in a murine E.G7 thymoma model. Together, our findings highlight HBHA as an immune adjuvant that favors Th1 polarization and DC function for potential applications in DC-based antitumor immunotherapy. Cancer Res; 71(8); 2858–70. ©2011 AACR.

Supplementary Methods, Figures 1-6 from Enhanced Efficacy of Therapeutic Cancer Vaccines Produced by Co-Treatment with Mycobacterium tuberculosis Heparin-Binding Hemagglutinin, a Novel TLR4 Agonist

CD117/c-kit, a tyrosine kinase receptor, plays a critical role in hematopoiesis, pigmentation, and fertility. The overexpression and activation of c-kit are thought to promote tumor growth and have been reported in various cancers, including leukemia, glioblastoma and mastocytosis. To disrupt the SCF/c-kit signaling axis in cancer, we generated a c-kit antagonist human antibody (NN2101) that binds to domain 2/3 of c-kit. This completely blocked the SCF-mediated phosphorylation of c-kit and inhibited TF-1 cell proliferation, erythroleukemia. In addition, the examination of binding affinity using surface plasmon resonance (SPR) assay showed that NN2101 can bind to c-kit of monkeys (KD = 2.92 × 10−10 M), rats (KD = 1.68 × 10−6 M), mice (KD = 11.5 × 10−9 M), and humans (KD = 2.83 × 10−12 M). We showed that NN2101 does not cause antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. The immunogenicity of NN2101 was similar to that of bevacizumab. Furthermore, the crystal structure of NN2101 Fab was determined and the structure of NN2101 Fab:c-kit complex was modeled. Structural information, as well as mutagenesis results, revealed that NN2101 can bind to the SCF-binding regions of c-kit. Collectively, we generated a c-kit neutralizing human antibody (NN2101) for the treatment of erythroleukemia and characterized its biophysical properties. NN2101 can potentially be used as a therapeutic antibody to treat different cancers.

5,3'-Dihydroxy-6,7,4'-trimethoxyflavanone (DHTMF) is one of the constituents of Vitex rotundifolia, a medicinal herb that is used for the treatment of various disorders in China and Korea. In this study we evaluated the antitumor and antiangiogeneic activities of DHTMF. DHTMF significantly suppressed growth and induced apoptosis in lung carcinoma cells in a dose-dependent manner, as indicated by a decrease in Bcl-2 levels and increases in Bax and cleaved caspase-3 levels. In addition, DHTMF treatment significantly reduced the phosphorylation of Akt and mammalian target of rapamycin (mTOR), accompanied by reductions in the protein level of hypoxia-inducible factor (HIF-1α) and vascular endothelial growth factor (VEGF), which are key angiogenic molecules in H522 lung cancer cells. Furthermore DHTMF inhibited VEGF-induced angiogenesis, as indicated by reduced expression of CD34, tube formation and migration in human umbilical vein endothelial cells (HUVECs), as well as reduced neovascularization in an in vivo mouse Matrigel plug assay. DHTMF also inhibited phosphorylation of Akt, mTOR, and p70S6K in HUVECs and lung cancer cells. Taken together, our finding indicated that DHTMF inhibits Akt/mTOR signaling and reduces the expression of HIF-1 α and VEGF in tumor cells, which in turns inhibits endothelial cell-mediated angiogenesis. These results suggest that DHTMF inhibits angiogenesis as well as induces apoptosis via the Akt/mTOR pathway and might elicit pharmacological effects that are useful for treatment of lung cancer.

In May 2015, Middle East respiratory syndrome coronavirus infection was laboratory confirmed in South Korea. Patients were a man who had visited the Middle East, his wife, and a man who shared a hospital room with the index patient. Rapid laboratory confirmation will facilitate subsequent prevention and control for imported cases.

Background Sagunja-Tang (SGT-4) is a traditional herbal formula in Korean medicine that is used to treat anti-metabolic syndrome, and has antioxidant activity. In this study, we evaluated the effects of SGT-4 on the formation efficiency of induced pluripotent stem cells (iPSCs) from human foreskin fibroblasts (HFFs) by four reprogramming transcription factors: Oct4, Sox2, KIf4, and c-Myc (OSKM). Methods SGT-4 contained four different herbal medicines that are composed of Ginseng Radix, Glycyrrhizae Radix et Rhizoma, Atractylodis Rhizoma Alba, and Poria Sclerotium. The composition of SGT-4 was analyzed by high-performance liquid chromatography (HPLC). HFFs were transfected with episomal vectors contained by four OSKM. Western blotting, RT-PCR, immunofluroescence, and in vitro differentiation were used to assess the pluripotency of the iPSC cells. Results SGT-4 exhibited antioxidant activity against the generation of intracellular reactive oxygen species (ROS) as well as promoted the activation of superoxide dismutase 1 (SOD1), catalase, gluthathione peroxidase 1 (GPX1), and glutathione (GSH). Moreover, the ATP level was not significantly fluctuated depending on the concentration of SGT-4 in the hiPSCs. Conclusion Our results indicate that the SGT-4, herbal formula significantly increases the efficiency of human iPSC generation via the transcription factors (Oct4, Sox2, KIf4, and c-Myc).

The full genome sequence of a Middle East respiratory syndrome coronavirus (MERS-CoV) was identified from cultured and isolated in Vero cells. The viral genome sequence has high similarity to 53 human MERS-CoVs, ranging from 99.5% to 99.8% at the nucleotide level.

Mycobacterium tuberculosis, the etiological factor of pulmonary tuberculosis, causes significant morbidity and mortality worldwide. Activation of host immune responses for containment of mycobacterial infections involves participation of innate immune cells, such as dendritic cells (DCs). In this study, we demonstrated that the gene encoding lipoamide dehydrogenase C (lpdC) from M. tuberculosis, Rv0462, induce maturation and activation of DCs involved in the MAPKs signaling pathway. Moreover, Rv0462-treated DCs activated naive T cells, polarized CD4+ and CD8+ T cells to secrete IFN-γ in syngeneic mixed lymphocyte reactions, which would be expected to contribute to Th1 polarization of the immune response. Our results suggest that Rv0462 can contribute to the innate and adaptive immune responses during tuberculosis infection, and thus modulate the clinical course of tuberculosis.

Effective activation of dendritic cells (DCs) toward T helper (Th)-1 cell polarization would improve DC-based antitumor immunotherapy, helping promote the development of immunotherapeutic vaccines based on T-cell immunity. To achieve this goal, it is essential to develop effective immune adjuvants that can induce powerful Th1 cell immune responses. The pathogenic organism Mycobacterium tuberculosis includes certain constitutes, such as heparin-binding hemagglutinin (HBHA), that possess a strong immunostimulatory potential. In this study, we report the first clarification of the functions and precise mechanism of HBHA in immune stimulation settings relevant to cancer. HBHA induced DC maturation in a TLR4-dependent manner, elevating expression of the surface molecules CD40, CD80, and CD86, MHC classes I and II and the proinflammatory cytokines IL-6, IL-12, IL-1β, TNF-α, and CCR7, as well as stimulating the migratory capacity of DCs in vitro and in vivo. Mechanistic investigations established that MyD88 and TRIF signaling pathways downstream of TLR4 mediated secretion of HBHA-induced proinflammatory cytokines. HBHA-treated DCs activated naïve T cells, polarized CD4+ and CD8+ T cells to secrete IFN-γ, and induced T-cell–mediated cytotoxicity. Notably, systemic administration of DCs that were HBHA-treated and OVA251–264-pulsed ex vivo greatly strengthened immune priming in vivo, inducing a dramatic regression of tumor growth associated with long-term survival in a murine E.G7 thymoma model. Together, our findings highlight HBHA as an immune adjuvant that favors Th1 polarization and DC function for potential applications in DC-based antitumor immunotherapy. Cancer Res; 71(8); 2858–70. ©2011 AACR.

Background Dendritic cell (DC)-based vaccines are currently being evaluated as a novel strategy for tumor vaccination and immunotherapy. However, inducing long-term regression in established tumor-implanted mice is difficult. Here, we show that deoxypohophyllotoxin (DPT) induces maturation and activation of bone marrow-derived DCs via Toll-like receptor (TLR) 4 activation of MAPK and NF-κB. Methods The phenotypic and functional maturation of DPT-treated DCs was assessed by flow cytometric analysis and cytokine production, respectively. DPT-treated DCs was also used for mixed leukocyte reaction to evaluate T cell-priming capacity and for tumor regression against melanoma. Results DPT promoted the activation of CD8+ T cells and the Th1 immune response by inducing IL-12 production in DCs. In a B16F10 melanoma-implanted mouse model, we demonstrated that DPT-treated DCs (DPT-DCs) enhance immune priming and regression of an established tumor in vivo. Furthermore, migration of DPT-DCs to the draining lymph nodes was induced via CCR7 upregulation. Mice that received DPT-DCs displayed enhanced antitumor therapeutic efficacy, which was associated with increased IFN-γ production and induction of cytotoxic T lymphocyte activity. Conclusion These findings strongly suggest that the adjuvant effect of DPT in DC vaccination is associated with the polarization of T effector cells toward a Th1 phenotype and provides a potential therapeutic antitumor immunity.

Dendritic cells (DC) are professional antigen-presenting cells that have the ability to detect infectious materials; antigens to T lymphocytes, and serve as a bridge between innate and adaptive immunities. DC express the ATP-binding cassette transporters P-glycoprotein (P-gp). P-gp is a 170-kDa transmembrane protein encoded by the mdr-1 gene, a member of highly conserved superfamily of ATP-binding cassette transport proteins. Functionally, P-gp transporters have been described to be required for efficient DC and T cell migration. We report for the first time, at the best of our knowledge, P-gp is also required for DC development and differentiation in mouse bone marrow-derived DC. In this study, we found that an mdr-1 gene and P-gp protein level was increased during DC development and LPS-induced maturation. Moreover, the activity of P-gp was increased LPS-induced DC maturation. Next, we have attempted to determine whether the modulation of P-gp regulates surface molecules expression and cytokine production in DC. Specifically, down-regulation of P-gp by Venlafaxine (VLX) inhibits the differentiation of DC and cytokine production, such as IL-1, IL-10, and IL-12 during DC maturation. Moreover, the P-gp-decreased DC by VLX was displayed impaired induction of T cell polarizations, proliferation, and cytokine production, including IFN-γ, IL-4, and IL-2. Taken together, these findings also broaden current perspective concerning our understanding of the immunopharmacological functions of VLX and the development of therapeutic adjuvants for the treatment of DC-related acute and chronic diseases.