首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 358 毫秒
1.
本实验探讨了人类bcl-2基因对小鼠NIH/3T3细胞增殖和存活能力的影响。结果表明,人类bcl-2基因转染对正常培养条件下的细胞的增殖和存活能力无明显影响,但能增加细胞对血清撤退和staurosporine(STS)两种致凋亡因素的抵抗作用。这一研究丰富了bcl-2基因调控细胞凋亡的资料,并为深入研究奠定了基础  相似文献   

2.
人类bcl┐2cDNA在哺乳类细胞中的表达及反义bcl┐2对U937细胞生物学行为的影响(摘要)何凤田1朱锡华1本文借助逆转录病毒载体将人类bcl-2cDNA转染于三种哺乳类细胞,建立了组成性稳定表达bcl-2的细胞模型,观察了模型细胞生长特性及对某...  相似文献   

3.
目的 建立一个用于比较研究哺乳动物细胞内表达基因和沉默基因的突变机理的实验模型。方法 以脂质体转染法将线性化的pMCLacI/Neo质粒导入NIH3T3细胞,用G418筛选,造反一个药物抗性细胞克隆进行扩增,用基因组Southern杂交,RT-PCR及RT-PCR Southern杂交进行了分子鉴定。结果 (1)在此细胞克隆的基因组中整合有pMCLacI/Neo质粒;(2)该质粒上的两个lacI靶  相似文献   

4.
目的 构建登革2型病毒E基因的真核表达载体,实现登革病毒E蛋白的真核表达。方法 采用逆录-多聚酶链反应(RT-PCR)扩增登革2型病毒(NGC株)包膜糖蛋白E基因全长片段,克隆人真核表达载体pcDNA3的Pcmv启动子下游,构建重组真核表达质粒pcDNA3-E,用脂质体转染法转染NIH3T3细胞,表达产物以免疫荧光、SDS-PAGE和蛋白质印迹进行分析检测。结果 成功构建了重组真核表达质粒pcDN  相似文献   

5.
随着基因治疗技术的发展和多个细胞因子基因的克隆,人们提出了供细胞因子的基因治疗的设想,以期为肿瘤、老年性痴呆、严重的造血功能障碍等这样一类难治疾病的治疗另辟蹊径。为改善放射损伤小鼠受抑制的造血功能,我们采用基因治疗的方法,将小鼠IL-3基因cDNA与逆转录病毒载体重组,转染包装细胞PA317,用其分泌的含IL-3cDNA的复制缺陷逆转录病毒感染、转化NIH3T3细胞,从中筛选可在体外分泌IL-3的克隆,将可分泌IL-3的细胞种植到放射损伤小鼠体内后发现:受体小鼠血清中检出了IL-3的活性;其外周血白细胞计数升至55万/mm3,以成熟中性粒细胞为主;肝、脾脏内有大量各个分化阶段的中性粒细胞。这些结果表明:可以利用基因治疗技术,在体内表达IL-3,改善机体的造血功能。  相似文献   

6.
刘昕  朱锡华 《免疫学杂志》1993,9(4):217-221
为了探讨放射损伤小鼠IL-3基因治疗可能性,本文作者将小鼠IL-3cDNA亚克隆到逆转录病毒载pLXSN上。将重组的逆转录病毒载体用电穿孔法和磷酸钙共沉淀法转染双向包装细胞系PA317,经新霉素类抗菌G418选择,得到了多个产病毒细胞克隆。用含有复缺陷病毒的产病毒细胞培养上清转化NIH3T3细胞,得到了数个自发分泌IL-3的克隆。在去掉G418,传代15代,约2个月后,这些克隆分泌IL-3的能力没  相似文献   

7.
Bcl—2核酶诱导SMMC7721细胞凋亡与p16,p21蛋白表达 …   总被引:1,自引:0,他引:1  
目的 观察bcl-2核酶对人肝癌细胞株SMMC-7721细胞的作用,并检测p16、p21的表达情况。探讨bcl-2核酶在肝癌治疗中的意义。方法 经脂质体介导的方法,将PMTr-neo(正向bcl-2核酶真核表达载体)导入SMMC7721细胞中。细胞克隆转移扩大培养后,彩用TUNEL法、免疫组化技术结合图像分析,在检测SMMC7271/PMTr-neo细胞凋亡的同时,检测p16,p21的表达。结果  相似文献   

8.
小鼠IL—3 cDNA转化细胞移植体内表达的初步研究   总被引:1,自引:0,他引:1  
随着基因治疗技术的发展和多个细胞因子基因的克隆,人们提出了供细胞因子的基因治疗的设想,以期为肿瘤、老年性痴呆、严重的造血功能障碍等这样一类难治疾病的治疗另辟蹊径。为改善放射损伤小鼠受抑制的造血功能,我们采用基因治疗的方法,将小鼠IL-3基因cDNA与逆转录病毒载体重组,转染包装细胞PA317,用其分泌的含IL-3 cDNA的复制缺陷逆转录病毒感染、转化NIH3T3细胞,从中筛选可在体外分泌IL-3  相似文献   

9.
目的 克隆获得编码人补体膜辅助调节蛋白(MCP)的cDNA,并对其在真核细胞的表达及功能进行研究。方法 应用RT-PCR 方法,从U937细胞总RNA中扩增编码人MCP分子的cDNA片段,快速克隆于pGEM-T Easy载体,测定共序列。将该片段重组于pLXSN载体,电穿孔转染NIH3T3细胞,经FACS检测筛选表达MCP的阳性细胞克隆,用补体容破试验鉴定其抑制人补体溶破的功能。结果 RT-PCR  相似文献   

10.
选择腊质休法将人转化生长因子(TGF-β1)基因转移至NIH/3T3中,经G418(450ug/ml)筛选,随机挑选出13个表达克隆;其培养上清经体外斌活(加热或酸化)处理,用水貂肺上皮细胞株CCL-64生长抑制法测定TGF。用活性,证明绝大多数表达克隆的TCF-β1表达量均超过了100ng/ml.48h,最高克隆表达量为156ng/ml·48h。选择高表达克隆经Southernblot、Northernblot鉴定,证实外源人TGF-β1基因稳定重组人NIH/3T3细胞中,有mRNA表达。PC…  相似文献   

11.
《Journal of neurogenetics》2013,27(2):165-173
3-Hydroxy-3-methylglutaric aciduria was found in a newborn infant whose parents are first cousins. The patient presented at 5 days of life with hyperammonemia, hypoglecemia, and metabolic acidosis. There was no ketonuria. Diagnosis was made by analysis of the pattern of organic acids excreted in the urine. A profound deficiency in activity of 3-hydroxy-3-methylglutaryl-coenzyme A lyase was found in cultured skin fibroblasts. The parents had intermediate levels of enzyme activity.  相似文献   

12.
Ptak and Askenase showed that both αβ and γδ cells are required for transfer of contact sensitivity (CS). This study confirms that day 4 immune cells depleted of γδ cells fail to transfer CS to trinitrochlorobenzene (TNP-Cl) systemically and demonstrates that administration of anti-γδ monoclonal antibodies (mAb) in vivo abolishes the CS reaction. Moreover, γδ cells accumulate at the antigen challenge site: these cells have the unusual phenotype CD8α+, CD8β-, IL-4 R+ which we suggest is due to their state of activation. Following immunization with contact sensitizer on the skin, the absolute number of γδ cells increases in the regional lymph nodes with a peak at 4 days. Of the γδ cells, 80%, both in the lymph nodes of TNP-Cl-immune mice and accumulating at the antigen challenge site are Vγ3+. The γδ cells expressing Vγ3, which is characteristic of dendritic epithelial T cells (DETC), obtained 4 days after sensitization, proliferate in response to interleukin (IL)-7, but only poorly to IL-2 and IL-4. They also respond to concanavalin A and immobilized anti-γδ mAb, but not to haptens or heat-shocked syngeneic spleen cells. Furthermore, injection of mice with mAb to IL-7 inhibits accumulation of Vγ3+ cells both in the lymph nodes after skin sensitization and at the antigen-challenge site. Altogether, these results strongly support the view that DETC are related to, or the original source of, the γδ cells found in the lymph node after skin sensitization and at the site of challenge, and that IL-7 is implicated in these phenomena.  相似文献   

13.
PurposeLong non-coding RNAs (lncRNAs) are essential regulators in the development of ovarian cancer (OC). Nonetheless, the function of lncRNA DNM3 opposite strand/antisense RNA (DNM3OS) in OC remains unclear. This work aimed to investigate the biological roles and underlying mechanisms of DNM3OS in OC.Materials and MethodsQuantitative real-time polymerase chain reaction was conducted to examine DNM3OS, microRNA (miR)-193a-3p, and mitogen-activated protein kinase 3 (MAP3K3) mRNA expression in OC tissues and cell lines. Kaplan-Meier survival analysis was employed to analyze the relationship between DNM3OS expression and the prognosis of OC patients. Cell counting kit-8, 5-ethynyl-2′-deoxyuridine, and transwell experiments were conducted to monitor cell proliferation, migration, and invasion, respectively. Western blot was applied to examine epithelial-mesenchymal transition associated protein (E-cadherin and N-cadherin) expression. Luciferase reporter gene and RNA immunoprecipitation experiments were performed to confirm the relationships among DNM3OS, miR-193a-3p, and MAP3K3. Pearson''s correlation analysis was adopted to analyze the correlations among DNM3OS, miR-193a-3p, and MAP3K3 mRNA.ResultsDNM3OS expression was remarkably increased in OC tissues and cell lines, which was associated with the unfavorable prognosis of the patients. DNM3OS overexpression enhanced OC cell proliferation, migration, and invasion; suppressed E-cadherin protein expression; and facilitated N-cadherin protein expression, while the transfection of miR-193a-3p mimics had the opposite effects. DNM3OS directly interacted with miR-193a-3p, and miR-193a-3p targeted MAP3K3 by directly binding to 3′UTR. DNM3OS could up-regulate the expression of MAP3K3 via repressing miR-193a-3p expression.ConclusionDNM3OS, as an oncogenic lncRNA, increases the malignancy of OC cells via regulation of an miR-193a-3p/MAP3K3 axis.  相似文献   

14.
The aim of our study was to compare CD3 expression on γδ T cells and αβ T cells in human patients. The antigen density of TCR and CD3 on both subsets was assessed by a quantitative method in eight patients. In parallel, we developed and validated a reliable direct tricolor staining protocol that we tested on samples from hospitalized and healthy individuals (n = 60). Our results demonstrate that human γδ T cells constitutively express approximately twofold more of the TCR/CD3 complex than αβ T cells. We suggest that this enhanced expression of the TCR/CD3 complex could contribute to the higher reactivity of γδ T cells compared to αβ T cells. These clinical laboratory results confirm the fundamental data described elsewhere. γδ T cells deserve further clinical investigations to understand their precise role in human immunity.  相似文献   

15.
16.
17.
γδ T cells play a crucial role in controlling malaria parasites. Dendritic cell (DC) activation via CD40 ligand (CD40L)‐CD40 signaling by γδ T cells induces protective immunity against the blood‐stage Plasmodium berghei XAT (PbXAT) parasites in mice. However, it is unknown which γδ T‐cell subset has an effector role and is required to control the Plasmodium infection. Here, using antibodies to deplete TCR Vγ1+ cells, we saw that Vγ1+ γδ T cells were important for the control of PbXAT infection. Splenic Vγ1+ γδ T cells preferentially expand and express CD40L, and both Vγ1+ and Vγ4+ γδ T cells produce IFN‐γ during infection. Although expression of CD40L on Vγ1+ γδ T cells is maintained during infection, the IFN‐γ positivity of Vγ1+ γδ T cells is reduced in late‐phase infection due to γδ T‐cell dysfunction. In Plasmodium‐infected IFN‐γ signaling‐deficient mice, DC activation is reduced, resulting in the suppression of γδ T‐cell dysfunction and the dampening of γδ T‐cell expansion in the late phase of infection. Our data suggest that Vγ1+ γδ T cells represent a major subset responding to PbXAT infection and that the Vγ1+ γδ T‐cell response is dependent on IFN‐γ‐activated DCs.  相似文献   

18.
In a search for proteins involved in signal transduction through the T cell receptor (TcR/CD3 complex), a recently developed highly efficient method for labeling of nucleotide binding proteins in permeabilized cells was applied. Here, we report that human CD3-γ could be labeled by periodate-oxidized [α-32P] GTP (GTPoxi). In contrast to GTPoxi labeling of CD3-ξ, (Peter, M. E., Hall, C, Ruhlmann, A., Sancho, J. and Terhorst, C, EMBOJ. 1992. 11: 933), GTP-specific labeling of CD3-γ reached a maximum when nucleotides were added 60 min prior to the cross-linking reaction. As CD3-γ did not contain a known consensus sequence for nucleotide binding and since labeling kinetics of CD3-γ coincided with those of cytosolic GTP-binding proteins, labeling may have been caused by a GTP-binding protein. This putative protein was not T cell specific because labeling of CD3-γ could also be achieved when expressed in the endoplasmic reticulum of Chinese hamster ovary (CHO) cells. In CHO cells, labeling by GTPoxi took place only when CD3-γ was associated with CD3-ξ, whereas labeling could not be established upon association of CD3-γ with CD3-δ or TcR α. The observation that CD3-γ was labeled without leaving the endoplasmic reticulum led to the hypothesis that the association of CD3-γ with a GTP-binding protein might be involved in an early step of the TcR/CD3 complex formation or transport.  相似文献   

19.
目的:观察神经肽Y对3T3L1前脂肪细胞增殖和分化的影响,并对其机制进行初步探讨。方法:3T3-L1细胞由3-异丁基-1-甲基黄嘌呤(3-isobutyl-1-methylxanthine,IB-MX)、胰岛素和地塞米松联合诱导分化,2 d后将细胞分为空白对照组(未加任何诱导剂组)、经典诱导组(胰岛素诱导)和NPY干预组(10-8、10-9、10-10mol/L NPY)。培养的第7、12天用相差显微镜观察各组细胞形态的变化,培养第12天用油红O染色观察脂肪细胞分化程度。MTT检测细胞增殖。Western blot检测脂肪细胞分化相关基因过氧化物体增殖剂活化受体-γ(peroxisome proliferator-activated receptor gamma,PPAR-γ)、CAAT/增强子结合蛋白-α(CCAAT/enhancer-bind-ing protein-α,C/EBP-α)蛋白的表达。结果:10-8mol/L NPY能促进3T3-L1细胞的分化。10-9mol/L NPY,10-8mol/L NPY均能促进3T3-L1细胞增殖。10-8mol/L NPY增加C/EBPα、PPARγ的表达。结论:NPY促进3T3L1前脂肪细胞的增殖和分化,其机制可能与上调PPARγ、C/EBPα的表达有关。  相似文献   

20.
The effect of IFN-γ to stimulate formation of nitric oxide (NO) by normal murine peritoneal macrophages (Mϕ) has been found to be completely dependent on the ability of IFN-γ to activate secretion of TNF-α. The NO-stimulatory effect of IFN-γ was abolished by anti-TNF-α antibodies, the inhibitory intervention of which could be fully reversed by exogenously supplied TNF-α. Accordingly, the failure of Mϕ from C3H/HeJ mice to secrete TNF-α upon stimulation with IFN-γ was associated with their complete incapability to generate NO, unless they were simultaneously treated with IFN-γ + TNF-α. Collectively, the data document that similar to the NO up-regulatory action of other cytokines, the effect of IFN-γ is not independent, but depends on a synergistic cooperation with the self-produced TNF-α. The findings thus indicate that a widespread opinion claiming that IFN-γ per se is able to stimulate biosynthesis of NO needs revision.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号