Exosomes （EXO） derived from dendritic cells （DC） and tumor cells have been used to stimulate antitumor immune responses in animal models and in clinical trials. However, there has been no side-by-side comparison o...Exosomes （EXO） derived from dendritic cells （DC） and tumor cells have been used to stimulate antitumor immune responses in animal models and in clinical trials. However, there has been no side-by-side comparison of the stimulatory efficiency of the antitumor immune responses induced by these two commonly used EXO vaccines. In this study, we selected to study the phenotype characteristics of EXO derived from a transfected EG7 tumor cells expressing ovalbumin （OVA） and OVA-pulsed DC by flow cytometry. We compared the stimulatory effect in induction of OVA-specific immune responses between these two types of EXO. We found that OVA protein-pulsed DCOVA-derived EXO （EXODC） can more efficiently stimulate naive OVA-specific CD8^＋ T cell proliferation and differentiation into cytotoxic T lymphocytes in vivo, and induce more efficient antitumor immunity than EG7 tumor cell-derived EXO （EXOEG7）. In addition, we elucidated the important role of the host DC in EXO vaccines that the stimulatory effect of EXO is delivered to T cell responses by the host DC. Therefore, DC-derived EXO may represent a more effective EXO-based vaccine in induction of antitumor immunity. Cellular ＆ Molecular Immunology. 2006;3（3）：205-211.展开更多
Ulcerative colitis （UC） is an inflammatory disease of the rectal and colonic mucosa and seems to result from a complex series of interactions between susceptibility genes, the environment and the immune system. Vari...Ulcerative colitis （UC） is an inflammatory disease of the rectal and colonic mucosa and seems to result from a complex series of interactions between susceptibility genes, the environment and the immune system. Various components of the mucosal immune system are implicated in the immunopathogenesis of UC. Evidence from animal models also suggests that an altered immune response to the commensal microflora of the host plays a central role in the development of UC. So in this review, we elucidate the cells and molecules which are implicated in the immunopathogenesis of the disease from four aspects： antigens in the intestine, dendritic cells, toll like receptors and NF-κB in the UC.展开更多
目的:观察中药单体青藤碱对类风湿关节炎患者外周血树突状细胞toll样受体(toll like receptor,TLR)2和TLR4表达的影响。方法:分离10例类风湿关节炎患者的单核细胞,采用细胞因子刺激分化为树突状细胞。分别采用青藤碱高(5mM)、中(2mM)、...目的:观察中药单体青藤碱对类风湿关节炎患者外周血树突状细胞toll样受体(toll like receptor,TLR)2和TLR4表达的影响。方法:分离10例类风湿关节炎患者的单核细胞,采用细胞因子刺激分化为树突状细胞。分别采用青藤碱高(5mM)、中(2mM)、低(1mM)剂量和空白对照干预。实时荧光定量PCR检测各组树突状细胞TLR2和TLR4 mRNA的表达,Western-blot检测树突状细胞TLR2和TLR4蛋白的表达。结果:与对照组相比,经青藤碱高(P<0.01)、中剂量(P<0.01)干预后的树突状细胞TLR2和TLR4 mRNA表达明显降低,青藤碱干预后的树突状细胞(DC)中TLR2、TLR4表达均有所有降低。结论:青藤碱可能通过抑制树突状细胞TLR介导的炎症信号转导,而产生治疗类风湿关节炎的作用。展开更多
AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological character...AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological characteristics and induction of specific CTL activity of H(22)-DC. METHODS: DCs were isolated from murine spleen by metrizamide density gradient centrifugation, purified based on its characteristics of semi-adhesion to culture plates and FcR-,and were cultured in the medium containing GM-CSF and IL-4. A large number of DC were harvested. DCs were then fused with H(22) cells by PEG and the fusion cells were marked with CD11c MicroBeads. The H(22)-DC was sorted with Mimi MACS sorter. The techniques of cell culture, immunocytochemistry and light microscopy were also used to test the characteristics of growth and morphology of H(22)-DC in vitro. As the immunogen, H(22)-DC was inoculated subcutaneously into the right armpit of BALB/C mice, and their tumorigenicity in vivo was observed. MTT was used to test the CTL activity of murine spleen in vivo. RESULTS: DC cells isolated and generated were CD11c+ cells with irregular shape, and highly expressed CD80, CD86 and CD54 molecules. H22 cells were CD11c- cells with spherical shape and bigger volume, and did not express CD80, CD86 and CD54 molecules.H(22)-DC was CD11c+ cells with bigger volume, being spherical, flat or irregular in shape, and highly expressed CD80, CD86 and CD54 molecules, too. H(22)-DC was able to divide and proliferate in vitro, but its activity of proliferation was significantly decreased as compared with H(22) cells and its growth curve was flatter than H(22) cells. After subcutaneous inoculation over 60 days, H(22)-DC showed no tumorigenecity in mice, which was significantly different from control groups (P【0.01). The spleen CTL activity against H(22) cells in mice implanted with fresh H(22)-DC was significantly higher than control groups (P 【 0.01). CONCLUSION: H(22)-DC could significantly stimulate the specific CTL activity of murine sple展开更多
Upon antigen stimulation, naive T helper cells differentiate into distinct lineages to attain specialized properties and effector functions. TH17 cells, a recently identified lineage of CD4＋ effector T cells, play a ...Upon antigen stimulation, naive T helper cells differentiate into distinct lineages to attain specialized properties and effector functions. TH17 cells, a recently identified lineage of CD4＋ effector T cells, play a key role in the immune defense against fungi and extracellular bacteria, but also contribute to the pathogenesis of many autoimmune conditions. The differentiation of TH 17 cells is orchestrated by an intricate network of signaling pathways and transcriptional regulators in T cells. While the involvement of T cell-intrinsic pathways has been described extensively, we are just beginning to appreciate how TH17 cell development is shaped by extrinsic pathways, espec- ially the innate immune signals. Dendritic cells （DCs）, the most important cell type to bridge innate and adaptive immunity, drive TH17 cell differentiation by providing antigenic, costimulatory and cytokine signals. This is mediated by the recognition of innate and inflam- matory signals by DCs via pattern recognition receptors, cytokine receptors and other immunomodulatory receptors that in turn activate the intracellular signaling network. In particular, p38a MAP kinase has emerged as a critical pathway to program DC-dependent TH17 cell differentiation by integrating multiple instructive signals in DCs. Here, we summarize the current knowledge on the mechanisms by which DC-derived innate immune signals drive TH17 cell differentiation.展开更多
文摘Exosomes （EXO） derived from dendritic cells （DC） and tumor cells have been used to stimulate antitumor immune responses in animal models and in clinical trials. However, there has been no side-by-side comparison of the stimulatory efficiency of the antitumor immune responses induced by these two commonly used EXO vaccines. In this study, we selected to study the phenotype characteristics of EXO derived from a transfected EG7 tumor cells expressing ovalbumin （OVA） and OVA-pulsed DC by flow cytometry. We compared the stimulatory effect in induction of OVA-specific immune responses between these two types of EXO. We found that OVA protein-pulsed DCOVA-derived EXO （EXODC） can more efficiently stimulate naive OVA-specific CD8^＋ T cell proliferation and differentiation into cytotoxic T lymphocytes in vivo, and induce more efficient antitumor immunity than EG7 tumor cell-derived EXO （EXOEG7）. In addition, we elucidated the important role of the host DC in EXO vaccines that the stimulatory effect of EXO is delivered to T cell responses by the host DC. Therefore, DC-derived EXO may represent a more effective EXO-based vaccine in induction of antitumor immunity. Cellular ＆ Molecular Immunology. 2006;3（3）：205-211.
文摘Ulcerative colitis （UC） is an inflammatory disease of the rectal and colonic mucosa and seems to result from a complex series of interactions between susceptibility genes, the environment and the immune system. Various components of the mucosal immune system are implicated in the immunopathogenesis of UC. Evidence from animal models also suggests that an altered immune response to the commensal microflora of the host plays a central role in the development of UC. So in this review, we elucidate the cells and molecules which are implicated in the immunopathogenesis of the disease from four aspects： antigens in the intestine, dendritic cells, toll like receptors and NF-κB in the UC.
文摘目的:观察中药单体青藤碱对类风湿关节炎患者外周血树突状细胞toll样受体(toll like receptor,TLR)2和TLR4表达的影响。方法:分离10例类风湿关节炎患者的单核细胞,采用细胞因子刺激分化为树突状细胞。分别采用青藤碱高(5mM)、中(2mM)、低(1mM)剂量和空白对照干预。实时荧光定量PCR检测各组树突状细胞TLR2和TLR4 mRNA的表达,Western-blot检测树突状细胞TLR2和TLR4蛋白的表达。结果:与对照组相比,经青藤碱高(P<0.01)、中剂量(P<0.01)干预后的树突状细胞TLR2和TLR4 mRNA表达明显降低,青藤碱干预后的树突状细胞(DC)中TLR2、TLR4表达均有所有降低。结论:青藤碱可能通过抑制树突状细胞TLR介导的炎症信号转导,而产生治疗类风湿关节炎的作用。
基金Supported jby the Natural Science Foundation of Guangdong Province China,No.980180
文摘AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological characteristics and induction of specific CTL activity of H(22)-DC. METHODS: DCs were isolated from murine spleen by metrizamide density gradient centrifugation, purified based on its characteristics of semi-adhesion to culture plates and FcR-,and were cultured in the medium containing GM-CSF and IL-4. A large number of DC were harvested. DCs were then fused with H(22) cells by PEG and the fusion cells were marked with CD11c MicroBeads. The H(22)-DC was sorted with Mimi MACS sorter. The techniques of cell culture, immunocytochemistry and light microscopy were also used to test the characteristics of growth and morphology of H(22)-DC in vitro. As the immunogen, H(22)-DC was inoculated subcutaneously into the right armpit of BALB/C mice, and their tumorigenicity in vivo was observed. MTT was used to test the CTL activity of murine spleen in vivo. RESULTS: DC cells isolated and generated were CD11c+ cells with irregular shape, and highly expressed CD80, CD86 and CD54 molecules. H22 cells were CD11c- cells with spherical shape and bigger volume, and did not express CD80, CD86 and CD54 molecules.H(22)-DC was CD11c+ cells with bigger volume, being spherical, flat or irregular in shape, and highly expressed CD80, CD86 and CD54 molecules, too. H(22)-DC was able to divide and proliferate in vitro, but its activity of proliferation was significantly decreased as compared with H(22) cells and its growth curve was flatter than H(22) cells. After subcutaneous inoculation over 60 days, H(22)-DC showed no tumorigenecity in mice, which was significantly different from control groups (P【0.01). The spleen CTL activity against H(22) cells in mice implanted with fresh H(22)-DC was significantly higher than control groups (P 【 0.01). CONCLUSION: H(22)-DC could significantly stimulate the specific CTL activity of murine sple
文摘Upon antigen stimulation, naive T helper cells differentiate into distinct lineages to attain specialized properties and effector functions. TH17 cells, a recently identified lineage of CD4＋ effector T cells, play a key role in the immune defense against fungi and extracellular bacteria, but also contribute to the pathogenesis of many autoimmune conditions. The differentiation of TH 17 cells is orchestrated by an intricate network of signaling pathways and transcriptional regulators in T cells. While the involvement of T cell-intrinsic pathways has been described extensively, we are just beginning to appreciate how TH17 cell development is shaped by extrinsic pathways, espec- ially the innate immune signals. Dendritic cells （DCs）, the most important cell type to bridge innate and adaptive immunity, drive TH17 cell differentiation by providing antigenic, costimulatory and cytokine signals. This is mediated by the recognition of innate and inflam- matory signals by DCs via pattern recognition receptors, cytokine receptors and other immunomodulatory receptors that in turn activate the intracellular signaling network. In particular, p38a MAP kinase has emerged as a critical pathway to program DC-dependent TH17 cell differentiation by integrating multiple instructive signals in DCs. Here, we summarize the current knowledge on the mechanisms by which DC-derived innate immune signals drive TH17 cell differentiation.
