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81.
82.
目的研究B7-2基因修饰肿瘤后对T细胞活化的影响,探索B7-2在肿瘤免疫治疗中的作用。方法构建B7-2基因的表达载体,转染Bel-7402细胞,与外周血单核细胞(PBMC)共孵育,利用流式细胞术(FCM)检测Bel-7402细胞的凋亡。结果 B7-2基因修饰的Bel-7402细胞和PBMC细胞共培养4 h后,凋亡率为12.7%,与对照组(7.5%)比较,细胞凋亡率显著增加(P〈0.01)。结论 B7-2基因修饰能够增强肿瘤细胞对淋巴细胞的活化作用,为基于B7-2的抗肿瘤治疗奠定了基础。 相似文献
83.
López MN Pesce B Kurte M Pérez C Segal G Roa J Aguillón JC Mendoza-Naranjo A Gesser B Larsen C Villablanca A Choudhury A Kiessling R Salazar-Onfray F 《Immunobiology》2011,216(10):1117-1126
We have previously demonstrated that IT9302, a nonameric peptide homologous to the C-terminal domain of human IL-10, mimics several effects of the cytokine including down-regulation of the antigen presentation machinery and increased sensitivity of tumor cells to NK-mediated lysis. In the present report, we have explored a potential therapeutic utility for IT9302 related to the ex vivo production of tolerogenic dendritic cells (DCs). Our results indicate that IT9302 impedes human monocyte response to differentiation factors and reduces antigen presentation and co-stimulatory capacity by DCs. Additionally, peptide-treated DCs show impaired capacity to stimulate T-cell proliferation and IFN-γ production. IT9302 exerts its effect through mechanisms, in part, distinct from IL-10, involving STAT3 inactivation and NF-κB intracellular pathway. IT9302-treated DCs display increased expression of membrane-associated TGF-β, linked to a more effective induction of foxp3+ regulatory T cells. These results illustrate for the first time that a short synthetic peptide can promote monocytes differentiation to tolerogenic DCs with therapeutic potential for the treatment of autoimmune and transplantation-related immunopathologic disease. 相似文献
84.
85.
Hensel A Maas M Sendker J Lechtenberg M Petereit F Deters A Schmidt T Stark T 《Journal of ethnopharmacology》2011,138(3):641-651
Ethnopharmacological relevance
Eupatorium perfoliatum L. originates from North America, where it has been widely used since centuries by native Indians. Additionally extracts are used also in Europe as immunostimulating agent for treatment of fever and cold. The following review summarizes published data on phytochemistry, ethnopharmacological use, as well as clinical and preclinical data.Materials and methods
Literature survey was performed via SciFinder® on papers and patents and by systematic research in ethnopharmacological literature at various university libraries.Results
The phytochemical composition of Eupatorium perfoliatum is described in detail for volatile oil, caffeic acid derivatives, flavonoids, sesquiterpene lactones, tannins, polysaccharides. Methods for analytical quality control, as well as specification for relevant lead structures can be deduced from published batch analysis. Preclinical studies indicate anti-inflammatory effects of ethanolic extracts, which can be correlated on a molecular level to eupafolin and sesquiterpen lactones. Antiplasmodial, antioxidative and immunomodulating activities are additionally discussed. Clinical data on the use of Eupatorium perfoliatum do not meet modern GCP requirements, but do indicate positive tendencies for use of ethanolic extracts for treatment of common colds.Conclusion
While the postulated immunostimulating properties of Eupatorium perfoliatum have not been confirmed by in vitro data, animal-studies and in vitro experiments with plant extracts both indicate antiinflammatory effects beside antiplasmodial effect against Plasmodium falciparum. Such an antiinflammation caused by the ethanolic extracts can be correlated well with clinical symptoms related to diseases as common cold, rheumatism, athritis etc. These data also support the plausibility of the plant's traditional use by the North American indigenous population and early European settlers. In principle quality aspects of the herbal material have to be affirmed by establishing modern pharmacopoeial control methods to guarantee constant and reliable quality. 相似文献86.
Ethnopharmacological relevance
Eupatorium perfoliatum L. has been used traditionally for the treatment of fever, malaria and inflammation-associated diseases. Nowadays it is mostly used as immune activating remedy. The following study was performed to evaluate extracts with different polarity and defined lead-compounds from the herbal material on potential in vitro activities concerning immune cell activation, phagocytosis, and inflammation-related processes.Materials and methods
MeOH-, EtOH-, and DCM extracts, beside several subfractions and isolated polysaccharides, sesquiterpene lactones and flavonoids were prepared and characterized analytically from the aerial parts of E. perfoliatum. Immunological activity was tested within lymphocyte transformation test on PBMC, test on enhancement of phagocytosis and of NO-production by murine RAW 264.7 macrophages. Anti-inflammatory effects were assessed from LPS-stimulated RAW 264.7 cells by NO/iNOS quantification, gene array, real-time PCR and ELISA.Results
No stimulatory activity was found within lymphocyte transformation test, for phagocytic activity and NO formation in macrophages. MeOH-, EtOH- and DCM extracts showed anti-inflammatory activity against LPS-stimulated macrophages by inhibition of NO release (IC50 > 100, 89, 19 μg/mL resp.) with eupafolin and a dimeric guaianolide having prominent NO inhibiting activity (IC50 6 resp. 16 μM). Anti-inflammatory activity was found on gene and protein level by significant down-regulation of cytokines CSF-3, IL-1α, IL-1β, and chemokines CCL2, CCL22 and CXCL10. Also TNF was down-regulated moderately (−17%).Conclusions
Although the postulated immunostimulating properties of E. perfoliatum have not been confirmed, the anti-inflammatory effects can be seen as a verification of the traditional use against inflammatory diseases. 相似文献87.
红花多糖对人PBMC和CD8+T细胞增殖作用的影响 总被引:1,自引:0,他引:1
目的探讨红花多糖(safflower polysaccharide,sPs)体外对人外周血单个核细胞(PBMC)和CD8+T细胞增殖作用的影响。方法采用葡聚糖-泛影葡胺密度梯度离心法(ficoll-hypaque density gradient centrifugation)从健康成人外周血中分离PBMC,在体外与不同浓度的SPS共同培养,用3H-TdR法检测PBMC增殖活性;流式细胞术检测CI)8+T细胞的增殖情况。结果SPS能够促进PBMC增殖,尤其1.25g·L-1和0.625g·L-1。两组PBMC增殖作用明显,与对照组比较差异有统计学意义(P〈0.05);SPS对CD8+T细胞的增殖有促进作用,与对照组比较差异有统计学意义(P〈0.05)。结论SPS可促进PBMC、CD8+T细胞的增殖,增强机体非特异性和特异性免疫功能。 相似文献
88.
Tanzeel Ahmed Ashok K. Tripathi Sanvidhan G. Suke Vivek Kumar Rafat S. Ahmed Shukla Das Basu Dev Banerjee 《Toxicology in vitro》2009,23(7):1319-1325
Malathion exerts cholinergic effects at high doses. However, a consequence of low dose (non-cholinergic) exposure causes immunotoxicity and oxidative stress. Hence, this study was designed to find out (i) the cytotoxic and apoptotic effects of cholinergic and non-cholinergic doses of malathion using cultured peripheral blood mononuclear cells (PBMCs) and (ii) the role of GSH and HSP27 and (iii) protective effects of N-acetylcysteine (GSH inducer) and curcumin (HSP27 inducer). In low doses, malathion caused mild depletion of GSH, threefold increase in HSP27 level and a range bound cytotoxicity and apoptosis of PBMC. In contrast, cholinergic dose exposures caused severe GSH depletion and exhibited dose dependent cytotoxicity and necrosis without any significant effect on HSP27 levels. Curcumin increased the levels of HSP27 in PBMC only in presence of low doses and not at high doses of malathion. Both NAC and curcumin were able to prevent malathion-mediated apoptosis of PBMC effectively at non-cholinergic doses and at this concentration of malathion, HSP27 induction keeps apoptosis and GSH depletion under control. Also NAC and curcumin may act as potential therapeutic agents to prevent malathion-induced immunotoxicity. 相似文献
89.
抗病毒治疗对Ⅰb型慢性丙肝患者PBMC IL-10、IL-12水平变化影响的研究 总被引:1,自引:0,他引:1
目的研究派罗欣联合利巴韦林抗病毒治疗对Ⅰb型慢性丙肝患者外周血单个核细胞(PBMC)分泌IL-10、IL-12水平的影响,分析IL-10、IL-12水平变化与病毒学应答结果之间的相关程度,探讨IL-10、IL-12作为抗病毒疗效评价指标的可能性。方法选取血清HCV-RNA阳性的Ib型慢性丙肝患者60例,依据病毒载量将其分为3组,低病毒载量组(1.0×103IU/ml 相似文献
90.
Brogren H Sihlbom C Wallmark K Lönn M Deinum J Karlsson L Jern S 《Thrombosis research》2008,122(2):271-281
The main inhibitor of intravascular fibrinolysis is plasminogen activator inhibitor 1 (PAI-1) which binds to and irreversibly inhibits tissue plasminogen activator (tPA). PAI-1 is present in blood, both in platelets and in plasma, and PAI-1 levels are associated with risk of atherothrombosis. Several tissues express PAI-1 but the source of plasma PAI-1 is not known. We recently found that platelets can de novo synthesize PAI-1 and the amount synthesized in vitro in 24 hours is 35-fold higher than required to maintain normal plasma levels. Recombinant human PAI-1 expressed in different cell types or secreted naturally by human cell lines, exhibit heterogeneous glycosylation patterns. The aim of this study was to investigate the hypothesis that platelets might be the source of plasma PAI-1 and that the cellular source of PAI-1 can be determined by its tissue-specific glycosylation pattern. PAI-1 was isolated from platelets, macrophages, endothelial cells, adipose tissue, as well as plasma from lean and obese subjects. The glycosylation was analyzed by nanoLC-MS/MS. PAI-1 isolated from cell lysates and conditioned media from macrophages, endothelial cells, and adipose tissue expressed heterogeneous glycosylation patterns. By contrast, no glycans were detected on PAI-1 isolated from plasma or platelets from healthy lean individuals. Hence, our data suggest that platelets may be the main source of plasma PAI-1 in lean individuals. Interestingly, plasma PAI-1 from obese subjects had a glycan composition similar to that of adipose tissue suggesting that obese subjects with elevated PAI-1 levels may have a major contribution from other tissues. 相似文献