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1.
Objective: To investigate the anti-tumor efficacy of dendritic cell (DC)-based vaccines pulsed with tumor extracts or RNA in a mouse model of intracranial G422 glioblastoma. Methods: Bone marrow-derived DCs were pulsed ex vivo with tumor extracts or RNA. Ninety female mice harboring 4-day-old intracranial G422 glioblastomas and 126 normal mice were treated with three spaced one week apart subcutaneous injections either with PBS, unpulsed DCs, G422 tumor extracts, RNA, DCs pulsed with G422 tumor extracts (DC/extract) or with RNA (DC/RNA). Seven days after the third immunization of normal mice, the spleens of 36 of them were harvested for cytotoxic T lyphocyte (CTL) assays and the others were challenged in the brain with G422 tumor cells. All the treated mice were followed for survival. Some mice brains were removed and examined pathologically when they died. Results: Immunization using DC/extract or DC/RNA significantly induced G422-specific CTL responses compared with control groups (P<0.01). Vaccinatio  相似文献   

2.
Objective: To investigate the anti-tumor efficacy of dendritic cell (DC)-based vaccines pulsed with tumor extracts or RNA in a mouse model of intracranial G422 glioblastoma. Methods: Bone marrow-derived DCs were pulsed ex vivo with tumor extracts or RNA. Ninety female mice harboring 4-day-old intracranial G422 glioblastomas and 126 normal mice were treated with three spaced one week apart subcutaneous injections either with PBS, unpulsed DCs, G422 tumor extracts, RNA, DCs pulsed with G422 tumor extracts (DC/extract) or with RNA (DC/RNA). Seven days after the third immunization of normal mice, the spleens of 36 of them were harvested for cytotoxic T lyphocyte (CTL) assays and the others were challenged in the brain with G422 tumor cells. All the treated mice were followed for survival. Some mice brains were removed and examined pathologically when they died. Results: Immunization using DC/extract or DC/RNA significantly induced G422-specific CTL responses compared with control groups (P<0.01). Vaccination with DC/extract or DC/RNA, either prior to G422 tumor challenge or in tumor-harboring mice, significantly prolonged survival compared with other control groups (P<0.01). Conclusion: DCs pulsed with tumor extracts or RNA derived from autologous tumors has potential antitumor effects via activation of cell-mediated immunity. Our results suggest a useful therapeutic strategy against gliomas.  相似文献   

3.
The growth inhibitory effects of D-glucosamine hydrochloride (GlcNH2-HCl), D-glucosamine (GlcNH2) and N-acetyl glucosamine (NAG) on human hepatoma SMMC-7721 cells in vitro were investigated. The results showed that GlcNH2.HCl and GlcNH2 resulted in a concentration-dependent reduction in hepatoma cell growth as measured by MTT (3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide) assay. This effect was accompanied by a marked increase in the proportion of S cells as analyzed by flow cytometry. In addition, human hepatoma SMMC-7721 cells treated with GlcNH2-HCl resulted in the induction of apoptosis as assayed qualitatively by agarose gel electrophoresis. NAG could not inhibit the proliferation of SMMC-7721 cells. GlcNH2-HCl exhibited antitumor activity against Sarcoma 180 in Kunming mice at dosage of 125-500 mg/kg, dose of 250 mg/kg being the best. GlcNH2-HCl at dose of 250 mg/kg could enhance significantly the thymus index, and spleen index and could promote T lymphocyte proliferation induced by ConA. The antitumor effect of GlcNH2-HCl is probably host-mediated and cytocidal.  相似文献   

4.
Objective: To study the role of calpain in the mechanism of oxidative cataract through detecting the level of intracellular free Ca2 , the expression and proteolytic activity of calpain in the lens epithelial cells (LECs) of H2O2-induced cataract. Methods: Rat lenses were cultured in vitro and cataract was induced by H2O2. The level of intracellular free Ca2 was measured by fluorescence determination with fura-2/AM. The expression of m-calpain protein in LECs was detected with immunohistochemical method. The proteolytic activity in LECs was measured using a fluorogenic synthetic substrate. Results: There were significant differences of the level of intracellular free Ca2 (P=0.001, 0.000, 0.000), the expression of m-calpain (P=0.001, 0.000, 0.000) and the proteolytic activity of calpain (P=0.001, 0.000, 0.000) between H2O2-induced and control group at 6, 12 and 24 h, respectively. Conclusions: H2O2 can increase intracellular free Ca2 , then enhance the expression and proteolytic activity of calpain which may play a role in the mechanism of oxidative cataract of rat.  相似文献   

5.

Background

Tumor-derived exosomes were considered to be potential candidates for tumor vaccines because they are abundant in immune-regulating proteins, whereas tumor exosomal miRNAs may induce immune tolerance, thereby having an opposite immune function.

Objective

This study was designed to separate exosomal protein and depleted exosomal microRNAs (miRNAs), increasing the immune activity of exosomes for activating dendritic cell/cytokine-induced killer cells (DC/CIKs) against pancreatic cancer (PC).

Methods

PC-derived exosomes (PEs) were extracted from cultured PANC-1 cell supernatants and then ruptured; this was followed by ultrafiltered exosome lysates (UELs). DCs were stimulated with lipopolysaccharide (LPS), PE, and UEL, followed by co-culture with CIKs. The anti-tumor effects of DC/CIKs against PC were evaluated by proliferation and killing rates, tumor necrosis factor-α (TNF-α) and perforin secretion. Exosomal miRNAs were depleted after lysis and ultrafiltration, while 128 proteins were retained, including several immune-activating proteins.

Results

UEL-stimulated DC/CIKs showed a higher killing rate than LPS- and PE-stimulated DC/CIKs.

Conclusions

miRNA-depleted exosome proteins may be promising agonists for specifically activating DC/CIKs against PC.
  相似文献   

6.
The attenuating effect of daidzein (DAD on oxidative toxicity induced by Aroclor 1254 (A 1254) was investigated in mouse testicular cells. Cells were exposed to A1254 alone or with DAI. The oxidative damage was estimated by measuring malondialdehyde (MDA) formation, superoxide dismutase (SOD) activity and glutathione (GSH) content. Results show that A 1254 induced a decrease of germ cell number, an elevation in thiobarbituric acid reactive substances (TBARS) but a decrease in SOD activity and GSH content. However, simultaneous supplementation with DAI decreased TBARS level and increased SOD activity and GSH content. Consequently, dietary DAI may restore the intracellular antioxidant system to attenuate the oxidative toxicity of A1254 in testicular cells.  相似文献   

7.
INTRODUCTION Dendritic cells(DCs)are professional anti-gen-presenting cells(APC)that are responsible for the activation of undifferentiated T cells and the generation of primary T-cell responses(Cella et al.,1997).The specific role of DCs is to capture,process and present antigens to T cells.Immunogenic and inflammatory signals are responsible for the migra-tion of DCs from tissues to lymphoid organs where they initiate an immune response.These processes induce the maturation of DCs…  相似文献   

8.
目的:检测子宫内膜异位症患者手术前后外周血T淋巴细胞亚群变化,了解病人细胞免疫功能状况。方法:采用间接免疫荧光法检测子宫内膜异位症患者体内CD3~ 、CD4~ 、CD8~ 细胞水平,并取同龄正常妇女作为对照。结果:(1)手术前与正常妇女相比,子宫内膜异位症患者体内存在CD8~ 细胞比例升高,CD4~ 细胞比例和CD4~ /CD8~ 比值下降;(2)手术后病人CD8~ 细胞逐渐回降,而CD4~ 细胞和CD4~ /CD8~ 比值呈现回升趋势。结论:子宫内膜异位症患者存在T细胞免疫异常,这种异常可在手术治疗后得以恢复。  相似文献   

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11.
目的:探讨D-半乳糖(D-Gal)对小鼠脾淋巴细胞损伤的分子机理.方法:测定不同浓度D-Gal作用后小鼠淋巴细胞乳酸脱氢酶(LDH)、超氧化物歧化酶 (SOD)、琥珀酸脱氢酶(SDH)活性以及过氧化脂质(LPO)水平.结果:与对照组比较,LDH、SOD和SD H活性均有显著降低(P<0.01),LPO水平显著提高(P<0.01).结论:D-Gal能引起小鼠脾淋巴细胞及其功能的损伤.  相似文献   

12.
目的:采用Trizol一步法提取人肝癌细胞总RNA电转染人外周血树突状细胞(Dendritic Cell,DC),观察其对混合T淋巴细胞的体外激活效应。方法:通过密度梯度离心法分离人外周血单核细胞,用细胞因子体外培养诱导其成为DC。Trizol一步法提取人肝癌细胞总RNA。通过电转染法将人肝癌细胞总RNA导入DC内;通过混合淋巴细胞实验,获取DC激活的特异性效应T细胞。用MTT法测定效应T细胞的增殖率。结果:电转染方法可将人肝癌细胞总RNA导入DC;电转染前后DC分子表达无显著差异。转染了人肝癌细胞总RNA的DC可特异的激活T细胞且增殖率明显增强(P<0.05)。结论:电转染为人肝癌细胞总RNA导入DC提供技术上的可行性;转染了人肝癌细胞总RNA的DC可特异激活T细胞。  相似文献   

13.
Lyu  Sunjian  Yuan  Xuemei  Liu  Li  Zhang  Haiqi  Yu  Zhe  Hang  Xiaoying  Shi  Weida  Wu  Yinglei 《Journal of Zhejiang University. Science. B》2021,22(4):295-304
Trionyx sinensis Hemorrhagic Syndrome Virus(TSHSV) is an arterivirus newly discovered in Chinese softshell turtles. Little is known about the effect of antibodies against the virus or the distribution of the virus in different organs of infected turtles. In this study, a partial protein of TSHSV-HP4 was produced using a prokaryotic expression system, and its polyclonal antibody was generated. The polyclonal antibody was confirmed by western blot and dot enzyme-linked immunosorbent assay(dot-ELISA). The distribution of TSHSV in different organs of T. sinensis was examined by immunohistochemistry(IHC) and the expression of immune-related genes was analyzed using quantitative real-time polymerase chain reaction(qRT-PCR). The results indicated that the recombinant TSHSV-HP4 protein was successfully expressed, and the generated polyclonal antibody showed specific binding to viral particles in the lung tissues of infected turtles. The IHC assay indicated that the virus was highly localized in various cells, including intestinal lymphocytes,enterocytes, kidney epithelial cells, spleen cells, lung macrophages, and cardiomyocytes. The qRT-PCR analysis revealed that TSHSV was detected in all organs tested, including the lungs, liver, kidneys, spleen, and heart. The numbers of viral mRNA copies in lung and heart tissues were significantly higher in the virus-antibody group than in the virus group. The interferonstimulated genes(ISGs), myxovirus resistance protein 2(MX2) and radical S-adenosyl methionine domain containing 2(RSAD2) were highly upregulated in all groups of infected turtles. Antibody-dependent enhancement(ADE) seemed to occur after stimulation by the polyclonal antibody, because significantly greater expression of the two genes was detected in the virus-antibody group than in the virus group. Overall, these results are important in understanding the cell localization of TSHSV and the immune response of infected turtles.  相似文献   

14.
INTRODUCTION The association between oxidative stress andcataract formation is well known from both clinicaland experimental data. The mechanism throughwhich oxidative stress causes cataract has not yetbeen established. It is known that many kinds ofcataract are related to increased levels of calcium.This has raised interest in the involvement of cal-cium-activated proteases. Calpains are non-lysosomal, cysteine prote-ases activated by calcium, which are found in mostmammalian…  相似文献   

15.
Objective: To establish normally conditionally-immortalized human umbilical vein endothelial cells (HUVECs) by ectopic expression of the human telomerase catalytic enzyme (hTERT) and simian virus 40 large T (SV40 LT) antigen. Methods: Primary HUVECs were transfected with recombinant retrovirus containing hTERT or SV40 LT respectively. Subsequently drug resistant cell clones were screened and expanded for further studies. Endothelial cell biomarkers were confirmed by examination. Results: The morphological phenotype of the transfected cells was similar to the non-transfected cells. Von Willebrand factor, hTERT and SV40 LT could be detected in transfected HUVECs. Moreover, higher telomerase activity in transfected cells was maintained for over 50 population doublings compared with only low level of endogenous telomerase transiently at early population doublings in primary HUVECs. When exposed to TNF-α(tumor necrosis factor-α), the expression of E-selectin in transfected cells was significantly up-regulated, but no alteration of endothelial lipase was found. Conclusion: Ectopic coexpression of hTERT and SV40 LT can effectively immortalize HUVECs without tumorigenicity in vitro. Immortalized HUVECs may be an ideal target of further molecular function studies.  相似文献   

16.
Objective: In this paper we compared the two methods of cell sorting (magnetic cell sorting and flow cytometry sorting) for the isolation and function analysis of mouse CD4~+ CD25~+ regulatory T (Treg) cells, in order to inform further studies in Treg cell function. Methods: We separately used magnetic cell sorting and flow cytometry sorting to identify CD4~+ CD25~+ Treg cells. After magnetic cell separation, we further used flow cytometry to analyze the purity of CD4~+ CD25~+ Treg cells, trypan blue staining to detect cell viability, and propidium iodide (PI) staining to assess the cell viability. We detected the immune inhibition of CD4~+ CD25~+ Treg cells in the in vitro proliferation experiments. Results: The results showed that compared to flow cytometry sorting, magnetic cell sorting took more time and effort, but fewer live cells were obtained than with flow cytometry sorting. The CD4~+ CD25~+ Treg cells, however, obtained with both methods have similar immunosuppressive capacities. Conclusion: The result suggests that both methods can be used in isolating CD4~+ CD25~+ Treg cells, and one can select the best method according to specific needs and availability of the methodologies.  相似文献   

17.
目的研究不同剂量反应停及反应停协同环磷酰胺对小鼠荷瘤H22(肝癌)实体型肿瘤的影响。方法建立小鼠肝癌移植实体型肿瘤模型,比较不同剂量反应停对小鼠肝癌的影响,同时观察反应停协同环磷酰胺对小鼠肝癌的影响。通过研究反应停对小鼠迟发型变态反应的影响探究其免疫作用。结果反应停对小鼠荷瘤H22呈现明显剂量依赖性抑制作用,反应停与环磷酰胺具有协同抗小鼠肝癌作用。反应停对小鼠迟发型变态反应呈剂量依赖性促进作用。结论反应停具有抗肝癌作用,而且与环磷酰胺具有协同抗肿瘤作用,此作用与反应停抗免疫作用有关。  相似文献   

18.
甲苯/丙烯烷基化反应制备甲基异丙苯,为克服以往固体磷酸催化剂污染环境腐蚀设备的缺点,使用Y型沸石分子筛作催化剂.首先考察了预处理条件及反应温度对催化活性的影响,同时用硅酯对催化剂进行了改性.通过50小时的小试实验,结果表明:用6%硅酯改性、交换度为87.8%的Y型分子筛催化活性稳定,新制备及再生后的TH6催化剂用于烷基化反应.结果达到m/P=2.1,0-%<3.3%.  相似文献   

19.
Plexiform lesions (PLs), which are often accompanied by perivascular infiltrates of mononuclear cells, represent the hallmark lesions of pulmonary arteries in humans suffering from severe pulmonary arterial hypertension (PAH). Endothelial progenitor cells (EPCs) have been recently implicated in the formation of PLs in human patients. PLs rarely develop in rodent animal models of PAH but can develop spontaneously in broiler chickens. The aim of the present study was to confirm the presence of EPCs in the PLs in broilers. The immune mechanisms involved in EPC dysfunction were also evaluated. Lungs were collected from commercial broilers at 1 to 4 weeks of age. The right/total ventricle ratios indicated normal pulmonary arterial pressures for all sampled birds. Immunohistochemistry was performed to determine the expressions of EPC markers (CD133 and VEGFR-2) and proangiogenic molecule hepatocyte growth factor (HGF) in the lung samples. An EPC/lymphocyte co-culture system was used to investigate the functional changes of EPCs under the challenge of immune cells. PLs with different cellular composition were detected in the lungs of broilers regardless of age, and they were commonly surrounded by moderate to dense perivascular mononuclear cell infiltrates. Immunohistochemical analyses revealed the presence of CD133+ and VEGFR-2+ cells in PLs. These structures also exhibited a strong expression of HGF. Lymphocyte co-culture enhanced EPC apoptosis and completely blocked HGF-stimulated EPC survival and in vitro tube formation. Taken together, this work provides evidence for the involvement of EPCs in the development of PLs in broilers. It is suggested that the local immune cell infiltrate might serve as a contributor to EPC dysfunction by inducing EPC death and limiting their response to angiogenic stimuli. Broiler chickens may be valuable for investigating reversibility of plexogenic arteriopathy using genemodified inflammation-resistant EPCs.  相似文献   

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