13 resultados para Linfócitos T CD8 Positivos

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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Partial cDNA sequences of both CD8 beta and CD4-like (CD4L) genes of common carp (Cyprinus carpio L.) were isolated from thymus cDNA library by the method of suppression subtractive hybridization (SSH). Subsequently the full length cDNAs of carp CD8 and CD4L were obtained by means of 3' RACE and 5' RACE, respectively. The full length cDNA of carp CD8 is 1164 bp and encodes 207 amino acids including a signal peptide region of 24 amino acids, a transmembrane region of 23 amino acids from aa 167 to aa189 and an immunoglobulin V-set from aa 19 to aa 141. Similar to other species CD8 beta s,carp CD8 beta also lacks p56(lck) domain in the cytoplasmic region. The full length cDNA of carp CD4L is 2001 bp and encodes 458 amino acids including four immunoglobulin (Ig)-like domains in the extracellular region, a transmembrane region of 23 amino acids at the C-terminal region from aa 402 to aa 424 and a cytoplasmic tail. Similar to mammalian, avian CD4s and fugu CD4L, carp CD4L also has the conserved p56(lck) tyrosine kinase motif (C-X-C) in the cytoplasmic region. RT-PCR analysis demonstrated that carp CD8 beta and CD4L genes were both expressed predominantly in thymus. The results from this study can be used to understand the evolution of both the CD8 beta and CD4 molecules which can be used as markers for cytotoxic and helper T cells in carp. (c) 2007 Published by Elsevier Ltd.

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英文摘要: Rosetting, or forming a cell aggregate between a single target nucleated cell and a number of red blood cells (RBCs), is a simple assay for cell adhesion-mediated by specific receptor-ligand interaction. For example, rosette formation between sheep RBC and human lymphocytes has been used to differentiate T cells from B cells. Rosetting assay is commonly used to determine the interaction of Fc gamma-receptors (Fc gamma R) expressed on inflammatory cells and IgG-coated on RBCs. Despite its wide use in measuring cell adhesion, the biophysical parameters of rosette formation have not been well characterized. Here we developed a probabilistic model to describe the distribution of rosette sizes, which is Poissonian. The average rosette size is predicted to be proportional to the apparent two-dimensional binding affinity of the interacting receptor-ligand pair and their site densities. The model has been supported by experiments of rosettes mediated by four molecular interactions: Fc gamma RIII interacting with IgG, T cell receptor and coreceptor CD8 interacting with antigen peptide presented by major histocompatibility molecule, P-selectin interacting with P-selectin glycoprotein ligand 1 (PSGL-1), and L-selectin interacting with PSGL-1. The latter two are structurally similar and are different from the former two. Fitting the model to data enabled us to evaluate the apparent effective two-dimensional binding affinity of the interacting molecular pairs: 7.19x10(-5) mu m(4) for Fc gamma RIII-IgG interaction, 4.66x10(-3) mu m(4) for P-selectin-PSGL-1 interaction, and 0.94x10(-3) mu m(4) for L-selectin-PSGL-1 interaction. These results elucidate the biophysical mechanism of rosette formation and enable it to become a semiquantitative assay that relates the rosette size to the effective affinity for receptor-ligand binding.

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HIV感染以后,病毒蛋白的持续性产出导致免疫系统的持续性激活,引起Th1细胞的丢失,Th1细胞通过合成Ⅰ型细胞因子,抑制淋巴细胞的自发凋亡。另外,病毒蛋白或其他因素能够使CD4~(+)、CD8~(+) T细胞和APC转化为凋亡的效应细胞,通过Fas/FasL或其他途径引起细胞凋亡。HIV感染人体后凋亡细胞不仅有CD4~(+) T细胞,还包括B细胞、NK细胞、粒细胞、神经细胞和单细胞。凋亡作为机体的自我防护措施,在清除感染细胞的同时,并没有抑制HIV在单细胞/巨噬细胞内的复制,反而造成大量未感染细胞的凋亡,导致对HIV复制的失控,发展为严重的免疫缺陷,引起AIDS相关的机会性感染。

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 目的:探讨猪2猕猴延迟性异种移植排斥反应(DXR) 的发生机制。方法:建立湖北白猪2云南猕猴的腹腔异位心 脏移植模型,应用中华眼镜蛇毒因子(Y2CVF) 完全清除受者体内补体,并应用环孢素A(CsA) 、环磷酰胺(CTX) 和甲泼尼龙(M. P) 三联免疫抑制治疗。检测血清C3、C4、抗猪内皮细胞天然抗体,免疫组化方法染色检测移植物中C3、C5b29、IgG、IgM、细胞间 黏附分子21 ( ICAM21) 、肿瘤坏死因子2α(TNF2α) 、单核巨噬细胞(CD68) 、NK细胞(CD57) 、CD4 + T 细胞和CD8 + T 细胞的表达。 结果:移植心存活时间分别为8、10、13 和13 天,血清C3 和补体总活性均下降为0 ,抗猪内皮细胞天然抗体水平在移植后则有 一个更为明显的下降,在移植心失功前2~4 天开始天然抗体稍有回升,但较术前正常时仍明显偏低。移植心有程度不等的 C3、C4、C5b29、IgG及IgM 沉积,大量的单核细胞(50 %) ,少量的NK细胞(8 %~10 %) 、CD4 + T 细胞(15 %) 和CD8 + T 细胞 (25 %) 。移植物血管内皮细胞表面出现ICAM21 的表达上调,移植物间质中出现TNF2α的表达增加。结论:体液免疫和细胞免 疫参与猪2猕猴DXR 排斥反应的发生。

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 目的 观察单核细胞、NK细胞和T 细胞在猪2猕猴延迟性异种移植排斥反应(DXR) 中的作用。方法 建立湖北白猪2云南猕猴的腹腔异位心脏移植模型,实验分为2 组:对照组( n = 5) ,不使用中华眼睛蛇毒因( Y2CVF) ;实验组( n = 4) 应用Y2CVF 完全清除受者体内补体。2 组受 体猴均采用环孢素A(CsA) ,环磷酰胺(CTX) 和甲基强的松龙(MP) 三联免疫抑制治疗。免疫组织 化学方法检测移植心组织中细胞间黏附分子( ICAM)21 、肿瘤坏死因子( TNF)2α、单核细胞、NK 细 胞和T 细胞的表达。结果 对照组3 个移植心在15~60 min 内发生超急性排斥反应(HAR) ,另2 个分别存活22 h 及6 d ,移植心均未见明显的炎性细胞浸润及ICAM21 和TNF2α的表达。实验组 移植心存活时间分别为8 、10 、13 和13 d ,移植物浸润细胞中可见大量的单核细胞(50 %) ,少量的 NK细胞(8 %~10 %) ,CD4 + T 细胞(15 %) 和CD8 + T 细胞(25 %) 。移植物血管内皮细胞表面出现 ICAM21 的表达上调,移植物间质中出现TNF2α的表达增加。结论 单核细胞、NK细胞和T 细胞 介导的移植物损伤,在应用Y2CVF 处理的猪2猕猴DXR 发生中发挥重要作用 

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探讨蛇毒因子(CW)消耗补体对大鼠同种心脏移植急性排斥反应的影响。方法建立Wistar至sD大 鼠同种异位心脏移植模型,实验组经静脉注射CVF以消耗受体血清中补体,观察移植心存活时间,并从实验组和对照组中分别 抽取5只大鼠于术后1、3、5、6、7 d定时活杀,对比观察移植心急性排斥反应程度,血清补体活性以及CIM+、CD8+T细胞浸润程 度。结果使用CVF的实验组,其移植一fi,存活时间显著延长,平均达(32.39±23.82)d,部分移植心甚至达到长期存活,而对照 组为(6.60±0.65)d(P<0.01),病理检查及免疫组化证实实验组急性排斥反应程度、组织内C3沉积情况和CD4+、CD8+T细胞 浸润程度均较同期对照组明显减轻。结论CVF清除补体可抑制大鼠同种心脏移植急性排斥反应,显著延长移植心存活 时间。

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 观察猪到猕猴异种心脏移植超急性排斥反应时的免疫学及病理学变化。方法  采用猪到猕猴腹腔内异位心脏移植模型,检测发生超急性排斥反应者的血液中补体、天然抗体及T 淋巴细胞亚群的变化,并对移植心脏进行免疫组化(测定C3 、C4 、C5b29 、IgG及IgM 的沉积) 及病理学 分析。结果 发生超急性排斥反应时,血清补体C3 、C4 的含量、总补体活性及抗猪内皮细胞天然抗 体均有一定程度的下降;CD4 + / CD8 + T 淋巴细胞的比率也有所下降;移植心脏中均有补体C3 、C4 、 C5b29 的沉积, IgG及IgM 也均有沉积,但IgG和IgM 沉积强度的差异无统计学意义;病理学改变主 要为心肌间质弥漫性出血、水肿,毛细血管内普遍淤血。结论 补体通过经典途径激活参与猪到猕猴 异种心脏移植超急性排斥反应;超急性排斥反应时受者血中天然抗体水平明显下降;CD4 + T 淋巴细 胞可能参与异种移植超急性排斥反应过程并有所消耗;发生超急性排斥反应的移植物突出病理表现 为间质出血。

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以草鱼脑组织、中华鳖脑组织和胸腺细胞为抗原制备兔抗草鱼脑血清 (RACBS)、兔抗中华鳖脑血清 (RATBS)和兔抗中华鳖胸腺细胞血清 (RATTS)。补体依赖性细胞毒试验和不同组织对RATBS、RATTS的吸收试验结果表明 :中华鳖胸腺细胞和脑组织均存在Thy1抗原(亦称脑组织抗原或胸腺 -脑组织T细胞抗原 ) ;草鱼脑组织缺乏Thy1抗原。应用间接酶标免疫组化染色技术显示 :Thy1抗原阳性反应物沉淀于中华鳖胸腺细胞和外周一部分淋巴细胞表面。进一步用抗人白细胞分化抗原CD4、CD8单克隆抗体进行免疫组

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目的构建HIV-1C亚型gp120负载人树突状细胞(dentriti ccell,DC)疫苗,并对其体外功能进行初步检测。方法利用Amaxa细胞核转染技术将pcDNA3.1-gp120质粒转染至人成熟DC,以Western blot检测gp120的表达。通过流式细胞仪检测DC表面共刺激分子的变化、混合淋巴细胞反应、CD8+T细胞表面活化分子CD25的表达及其分泌IFN-γ的变化。结果通过Western blot检测,gp120在DC中得到了正确表达。经流式细胞仪检测,DC表面分子CD80表达率由刺激前的33.34%上升至43.20%,CD86表达率由刺激前的60.08%上升至90.34%;负载gp120DC刺激淋巴细胞增殖率为86.72%;CD8+T细胞表面分子CD25表达率由刺激前的5.27%上升至74.21%,IFN-γ的表达率达37%。结论负载了HIV-1gp120的人树突状细胞能够显著刺激淋巴细胞的增殖、增强CD8+T细胞表面活化分子CD25表达以及促进CD8+T细胞分泌IFN-γ,为下一步DC治疗性疫苗的体内研究奠定基础。

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therapeutic drugs, vaccines and mechanisms of human diseases. Little is known about the normal levels of leukocyte subpopulations of Chinese rhesus macaques. To obtain these data, 100 blood samples from Chinese rhesus macaques were collected. The normal range of major leukocyte subpopulations, such as T lymphocytes, B lymphocytes, monocytes, myeloid dendritic cells (mDCs) and plasmacytoid dendritic cells (pDCs), were quantitatively analyzed by flow cytometry through BD trucount tubes. The influence of age and sex on the cell counts of leukocyte subpopulations was analyzed. The counts of CD3+ T cells, CD3+CD4+ T cells, CD3+CD8+ T cells and B cells decreased with age, but those of monocytes, mDCs and pDCs had no significant correlation with age. Significant differences existed in the cell counts of most leukocyte subpopulations between the male and female groups except pDCs. Furthermore the values of the females were higher than those of the males. The study provided basic information about the leukocyte subpopulations of Chinese rhesus macaques, and it may be valuable for immunobiological study of Chinese rhesus macaques. Cellular & Molecular Immunology. 2009;6(6):433-440.

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CD4+CD25+调节性T细胞是1995年才发现的一个具有免疫抑制功能的T细胞亚群,主要通过细胞与细胞间直接接触和分泌抑制性细胞因子发挥作用,在维持机体免疫自稳、防止自身免疫以及肿瘤免疫、移植免疫等方面起着重要作用。有关Treg HIV/SIV病毒感染及AIDS的进展关系密切,但却有两种不同的观点。一种认为Treg的数量和功能受到损伤,从而导致宿主免疫系统过度活化。另一种则认为Treg在早期抑制了针对HIV/SIV的特异性的免疫反应,从而导致机体无法清除感染的病毒。本文利用动物模型对CD4+CD25+调节性T细胞在SIV感染后的数量和功能做了动态的检测,并对其中的机制做了初步的探讨。我们首先建立了SIVmac239病毒株对中国起源的恒河猴感染的动物模型,建立了前病毒的检测方法、血浆病毒载量的测定方法、血浆病毒特异性抗体的测定方法,以及病毒的分离方法,并获得了早期感染的相关数据。在研究中我们发现,SIV感染后的1周后即可在恒河猴外周单个核细胞DNA中检测到前病毒。病毒血症也在1周后出现,并很快达到高峰。不同的个体对病毒感染的体液免疫不尽相同,血浆抗体很快出现,但是99003猴抗体下降很快,而99083猴则保持了一定数量的抗体。同时,伴随SIV的感染进程的还有T淋巴细胞的数量变化,CD4+T细胞数量持续下降,而CD8+T细胞数量则在增加,出现CD4/CD8倒置的现象。以上说明恒河猴被SIV所成功感染。在该动物模型的基础上,我们利用体内传代的SIVmac239病毒株,对4只健康恒河猴进行了感染,并对CD4+CD25+调节性T细胞(Treg)亚群在数量上的变化进行了检测,并对其中的机制做了初步探讨。我们在研究中发现,外周血中的Treg在SIV感染后无论是绝对数量还是在占CD4+T细胞中的相对数量均有增加,而且Treg仍然保持了对靶细胞的抑制功能。对腹部淋巴结的分析显示,SIV感染后的一段时期内,该部位FoxP3 mRNA的表达水平也在上升,TGF-β、IL-10的转录也显著增加。前者可以通过抑制树突状细胞间接抑制效应细胞,而后者则是一个抑制性的细胞因子,可以直接作用于靶细胞。因此,我们推测SIV引起免疫系统的过度活化可能不是由于Treg功能的受损,其中的机制需要深入研究。 Treg表达CCR5表面分子(HIV辅助受体之一),同时也有CD4分子的表达,因此推测HIV/SIV可以感染Treg。但是国内外这方面的文献很少。我们对Treg中前病毒的检测发现,SIV可以感染Treg,而且对Treg的感染比例高于CD4+CD25-T细胞。这个结果与Treg绝对数量的上升的结果说明,SIV感染Treg但可能却没有杀伤Treg,因此Treg在数量上有所增加。不过,其中的机制仍有待于进一步的研究。在对SIV引起的体液免疫的研究中还发现,机体针对SIV不同抗原的抗体有不同的模式。部分抗原很快就产生了比较强的反应,但是却不能维持高水平的表达。而针对p27蛋白的抗体产生比较晚,但却长时间维持在比较高的水平。是否这样高水平的抗体有助于控制病毒复制是个值得探讨的问题。

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依据虎眼万年青组分中多糖对小鼠巨噬细胞吞噬功能的影响,筛选并优化出60%醇浓度中性多糖活性组分S3,进而研究其对体液免疫、细胞免疫及细胞因子变化的影响,并从细胞和分子水平探讨其作用的机理.方法:采用溶血素测定方法,测定S3对小鼠脾细胞溶血素抗体的诱导作用;采用3H-TdR渗入法,测定S3对ConA诱导小鼠脾淋巴细胞的增殖作用;采用3H-TdR后标记法,测定S3对NK细胞细胞毒活性的影响;以ELISA法测定S3对小鼠脾细胞IL-2产生的影响;利用流式细胞术,检测S3对T淋巴细胞亚群CD3、CD4、CD8、CD4/CD8阳性细胞百分率的影响;采用RT-PCR方法检测IL-2 mBNA的表达水平.结果:S3高、中剂量组能明显增强小鼠脾细胞溶血素抗体的形成(P<0.05);各剂量组均能明显增强ConA诱导的淋巴细胞增殖能力(P<0.001);各剂量组均能增强NK细胞的细胞毒活性并促进IL-2的产生(P<0.001,P<0.01);高、中剂量组CD8阳性细胞百分率明显降低(P<0.001),各剂量组均能显著地提高CD4/CD8阳性细胞百分率(P<0.001);高剂量组可明显促进脾细胞中细胞因子IL-2的mRNA表达,使表达量增加(P<0.05).结论:S3具有较强的增强机体多种免疫功能的作用,可利用开发为一种免疫增强药物.

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Objective:Developing a generalized psychological intervention program, and explore its influence on the emotion, subjective health, and immunity function of the perioperation patients with breast cancer. Method:Sixty patients with breast cancer were randomly divided into intervention and control groups. The clinical psychological intervention was performed on patients in the intervention group for 20 days, in addition to the routine therapy and care. Levels of emotion (SAS & SDS), subjective health (SF-36), and immunity function (t lymphocyte subsets) of the patients were tested. Results: 1.There was no significant difference between the age, income, educational level, and type of prefession of the two groups. There was no significant difference between SAS, SDS, SF-36 and lymphocyte subsets(CD3+, CD4+, CD8+, CD4+/CD8+, NK) of the two groups. 2. Scores of SAS and SDS decreased significantly after intervention in experimental group, while the score of SF-36, the average value of CD4+, CD4+/CD8+, and NK increased significantly. For the control group, the score of depression decreased significantly after intervention, while the score of PF, GH, VT, SF, RE, and MH increased significantly. 3. In comparison of the intervention and control group, the intervention effect of SAS, SDS, SF-36 scores (except SF), CD3+, CD4+, CD4+/CD8+, and NK differed significantly, with the priority of experimental group. 4. SDS, SAS, and CD3+, CD4+, NK correlated in negative respectively, while SDS, SAS, and CD8+ correlated in positive. PF, RP, GH, SF, and MH of subjective health correlated in positive with every index of immunity function in positive, except negative correlation with CD4+/CD8+. BP, RE correlated with CD3+,CD4+,CD8+, and NK in positive. VT correlated in positive with CD3+, CD8+, and NK, in negative with CD4+/CD8+. Conclusions: 1. Anxiety, depression, and subjective health, correlated with immunity function in perioperation patients with breast cancer. 2. Psychological intervention can improve the emotional status, subjective health, and immune function of patients with breast cancer to the optimum in perioperative period.