ABSTRACT
AIM:To evaluate the ability of dendritic cells (DCs) loaded with tumor lysate to initiate cell mediated immune responses by stimulating naive T cells, and the efficiency of activated T cells to kill autologous tumor cells in vitro. METHODS: The peripheral blood lymphocytes and monocytes were obtained from the advanced renal cell carcinoma patient by eonglutination method. The immature dendritic cells were generated in the presence of interleukin -4(IL-4) and granulocyte/macrophage colony-stimulating factor (GM-CSF) from monocytes of healthy individuals.These cells were pulsed with tumor lysate or not. Induction of tumor-specific cytotoxic T lymphocytes(CTLs) response by mature dendritic cells (mDCs) was evaluated by the CD95(Fas) expression assay through FCM and the cytotoxic assay a gninst autolognns human tumor cells. RESULTS: Human immature dendritic cells and T cells obtained from healthy donors were stimulated with tumor- pulsed dendritic cells. The immature dendritic cells were applied to the cytotoxicity assay a gainst target autologons tumor cells. The CD95 (Fas) expression, IFN-γ, and TNF -α secreted by the CTLs in tumor lysate-plused DC group were higher than those of other groups. The capacity of the CTLs to kill autolognns tumor cells was significantly different(P<0. 05). Antigen-specific DCs vaccine can induce T cells activation and proliferation, thus we can obtain higher proportion of tumor specific cytotoxic T cells(CTLs), and enhance the CTLs to secret IFN-γ and TNF-α. CONCLUSION: Our results indicate that monocyte-derived human dendritic cells pulsed with tumor lysate could in duce the specific antitumor effect against autologons tumors. This in vitro model offers a new and simple approach to the development of DC + CTL - based immunotherapy.
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Objective To study the changes of tissue plasminogen activator (t-PA), plasminogen activator inhibitor 1 (PAI-1), and soluble thrombomodulin (sTM) induced by dengue 2 virus (D 2V) infection of vascular endothelial cells. Methods The effects of D 2V infection on the production of t-PA, PAI-1, and sTM of human umbilical cord vein cells were studied. Results D 2V infection significantly induced the secretion of sTM and t-PA but showed no such effects on PAI-1 of human endothelial cells. Antibody against IL-6 inhibited D 2V-induced t-PA production of endothelial cells. A close correlation between serum levels of IL-6 and t-PA was found in dengue hemorrhagic fever (DHF) but not in dengue fever (DF) patients. Conclusion IL-6 can regulate D 2V-induced t-PA production of endothelial cells, suggesting that endothelial cells can be the target for D 2V infection and that D 2V-induced t-PA, TM, and IL-6 production of endothelial cells may contribute to the pathogenic development of dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS).
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Proteins in coagulative and fibrinolytic systems were measured in 50 type 2 diabetic patients and 50 normal controls. Proteins related with fibrinolytic system in the diabetic patients were significantly higher than those in normal controls. The concentration of soluble thrombomodulin (sTM) was negatively correlated with the activity of protein C and positively correlated with plasmin-? 2 -antiplasmin complex in type 2 diabetic patients, suggesting that the increase of sTM is associated with hypercoagulability and enhanced fibrinolysis.
ABSTRACT
AIM:To evaluate the ability of dendritic cells (DCs) loaded with tumor lysate to initiate cell-mediated immune responses by stimulating naive T cells, and the efficiency of activated T cells to kill autologous tumor cells in vitro. METHODS: The peripheral blood lymphocytes and monocytes were obtained from the advanced renal cell carcinoma patient by conglutination method. The immature dendritic cells were generated in the presence of interleukin-4(IL-4) and granulocyte/macrophage colony-stimulating factor(GM-CSF) from monocytes of healthy individuals. These cells were pulsed with tumor lysate or not. Induction of tumor-specific cytotoxic T lymphocytes (CTLs) response by mature dendritic cells (mDCs) was evaluated by the CD95(Fas) expression assay through FCM and the cytotoxic assay against autologous human tumor cells. RESULTS: Human immature dendritic cells and T cells obtained from healthy donors were stimulated with tumor-pulsed dendritic cells. The immature dendritic cells were applied to the cytotoxicity assay against target autologous tumor cells. The CD95(Fas) expression, IFN-? and TNF-? secreted by the CTLs in tumor lysate-plused DC group were higher than those of other groups. The capacity of the CTLs to kill autologous tumor cells was significantly different(P
ABSTRACT
AIM: The aim of this study is to elucidate the effects of lipopolysaccharide (LPS) on tissue plasminogen activator(tPA) and plasminogen activator inhibitor type-1(PAI-1) expression and secretion in endothelial cells. METHODS: Cultured human umbilical vein endothelial cells (HUVECs) were induced by LPS for different times. Cell viability was then determined by cell counting kit-8. tPA and PAI-1 activities in the media were assayed by fibrin overlay and reverse fibrin autograph, respectively. Cytoplasmic RNA was prepared using the Trizol method and was assayed for PAI-I and tPA mRNA levels by reverse transcript-polymerase chain reaction(RT-PCR). RESULTS: LPS(10 mg/L) did not produce cell toxicity according to LDH determination in culture media. PAI-1 activity in LPS group was high (P0.05). CONCLUSION: LPS (10 mg/L) did not show signs of cell toxicity, but promoted the expression of PAI-1 mRNA and induced an increase activity of PAI-1. However, LPS (10 mg/L) did not change tPA mRNA expression. The time-dependent increase in PAI-1 mRNA expression and activity shifts the local balance toword increased anti-fibrinolytic capacity, which can amplify the extent of acute thrombosis after plaque rupture. This is one of the possible reasons that cause thrombus,blood coagulation and disseminated intravascular coagulation (DIC) during septicemia.