Background Cilostazol, an anti-platelet drug for treating coronary heart disease, has been reported to modulate immune cell functions Plasmacytoid dendritic cells （pDCs） have been found to participate in the progres...Background Cilostazol, an anti-platelet drug for treating coronary heart disease, has been reported to modulate immune cell functions Plasmacytoid dendritic cells （pDCs） have been found to participate in the progression of atherosclerosis mainly through interferon ct （IFN-ct） production. Whether cilostazol influences pDCs activation is still not clear. In this study, we aimed to investigate the effects of cilostazol on cell activation and antigen presentation ofpDCs in vitro in this study. Methods Peripheral blood mononuclear cells isolated by Ficoll cen- trifugation and pDCs sorted by flow cytometry were used in this study. After pretreated with cilostazol for 2 h, cells were stimulated with CpG-A, R848 or virus for 6 h or 20 h, or stimulated with CpG-B for 48 h and then co-cultured with naive T cell for five days. Cytokines in supernatant and intracellular cytokines were analyzed by ELISA or flow cytometry respectively. Results Our data indicated that cilostazol could inhibit IFN-α and tumor necrosis factor α （TNF-α） production from pDCs in a dose-dependent manner. In addition, the ability of priming na ve T cells of pDCs was also impaired by cilostazol. The inhibitory effect was not due to cell killing since the viability of pDCs did not change upon cilostazol treatment. Conclusion Cilostazol inhibits pDCs cell activation and antigen presentation in vitro, which may explain how cilostazol protects against atherosclerosis.展开更多
Objective To explore the effect of oxLDL on CXC chemokine growth-regulated oncogene α (GROα) expression in human endothelial cells and the possible functional significance of the effect.Methods LDL was isolated by...Objective To explore the effect of oxLDL on CXC chemokine growth-regulated oncogene α (GROα) expression in human endothelial cells and the possible functional significance of the effect.Methods LDL was isolated by sequential ultracentrifugation and oxidized to oxLDL. Reverse transcription-polymerase chain reaction with GAPDH as internal standard was applied and CXC chemokine GROα mRNA in endothelial ECV304 cells was examined. ELISA was used to determine GROα protein expression on ECV304 cell surface and in the medium. With static cell adhesion assays, the physiological significance of elevated GROα expression was tested. Results OxLDL, not LDL, treatment of ECV304 cells significantly induced the expression of GROα mRNA that was not detectable in untreated cells. Induction of expression was first evident at 1?h, became maximal at 2?h, and was substantially decreased by 4?h. In a concentration- and time-dependent manner, oxLDL, and not LDL, induced a significant upregulation of GROα surface expression in ECV304 cells that was at a barely detectable level in unstimulated ECV304 cells. GROα protein in the medium did not change significantly. Exposure of ECV304 cells to 40?μg protein /ml oxLDL for 24?h resulted in a marked increase in the number of U937 cells bound to ECV304 cells and antibodies to GROα inhibited adhesion.Conclusion OxLDL functionally upregulated GROα expression in endothelial cells.展开更多
文摘Background Cilostazol, an anti-platelet drug for treating coronary heart disease, has been reported to modulate immune cell functions Plasmacytoid dendritic cells （pDCs） have been found to participate in the progression of atherosclerosis mainly through interferon ct （IFN-ct） production. Whether cilostazol influences pDCs activation is still not clear. In this study, we aimed to investigate the effects of cilostazol on cell activation and antigen presentation ofpDCs in vitro in this study. Methods Peripheral blood mononuclear cells isolated by Ficoll cen- trifugation and pDCs sorted by flow cytometry were used in this study. After pretreated with cilostazol for 2 h, cells were stimulated with CpG-A, R848 or virus for 6 h or 20 h, or stimulated with CpG-B for 48 h and then co-cultured with naive T cell for five days. Cytokines in supernatant and intracellular cytokines were analyzed by ELISA or flow cytometry respectively. Results Our data indicated that cilostazol could inhibit IFN-α and tumor necrosis factor α （TNF-α） production from pDCs in a dose-dependent manner. In addition, the ability of priming na ve T cells of pDCs was also impaired by cilostazol. The inhibitory effect was not due to cell killing since the viability of pDCs did not change upon cilostazol treatment. Conclusion Cilostazol inhibits pDCs cell activation and antigen presentation in vitro, which may explain how cilostazol protects against atherosclerosis.
文摘Objective To explore the effect of oxLDL on CXC chemokine growth-regulated oncogene α (GROα) expression in human endothelial cells and the possible functional significance of the effect.Methods LDL was isolated by sequential ultracentrifugation and oxidized to oxLDL. Reverse transcription-polymerase chain reaction with GAPDH as internal standard was applied and CXC chemokine GROα mRNA in endothelial ECV304 cells was examined. ELISA was used to determine GROα protein expression on ECV304 cell surface and in the medium. With static cell adhesion assays, the physiological significance of elevated GROα expression was tested. Results OxLDL, not LDL, treatment of ECV304 cells significantly induced the expression of GROα mRNA that was not detectable in untreated cells. Induction of expression was first evident at 1?h, became maximal at 2?h, and was substantially decreased by 4?h. In a concentration- and time-dependent manner, oxLDL, and not LDL, induced a significant upregulation of GROα surface expression in ECV304 cells that was at a barely detectable level in unstimulated ECV304 cells. GROα protein in the medium did not change significantly. Exposure of ECV304 cells to 40?μg protein /ml oxLDL for 24?h resulted in a marked increase in the number of U937 cells bound to ECV304 cells and antibodies to GROα inhibited adhesion.Conclusion OxLDL functionally upregulated GROα expression in endothelial cells.
