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81.
目的 建立测定B细胞激活因子 (B lymphocytestimulator ,BlyS)mRNA含量的荧光定量反转录 聚合酶链反应 (RT PCR)法 ,并用来检测自身免疫病 [系统性红斑狼疮 (SLE)、类风湿关节炎 (RA) ]患者外周血单个核细胞 (PBMCs)中BlyS的基因表达水平 ,探讨BlyS基因表达水平与自身免疫性疾病发病机制的关系。方法 构建克隆载体 pMD18 T BlyS作为定量模板 ,基于TaqMan荧光探针技术 ,建立实时荧光RT PCR方法在GeneAmp 5 70 0型检测仪上定量检测 19例自身免疫病(SLE、RA)确诊病人、2 0例亚临床病人 (主要是抗核抗体阳性 )、8例其他对照性疾病患者 (自身抗体阴性 ,免疫球蛋白升高 )、2 0名正常健康献血者的外周血BlySmRNA表达含量。结果  19例自身免疫病确诊病人的PBMCs中均有BlySmRNA的表达 ,范围从 9 7× 10 5~ 3 2× 10 8拷贝 /μgRNA ,均值为 (8 4± 7 9)× 10 7拷贝 /μgRNA ;2 0例亚临床病人的强度为 8 6× 10 4~ 3 8× 10 6拷贝 /μgRNA ,均值为 (1 3± 1 2 )× 10 6拷贝 /μgRNA ;2 0名正常健康人的强度为 5 5× 10 4~ 4 9× 10 5拷贝 /μgRNA ,均值为 (1 7± 1 4 )× 10 5拷贝 /μgRNA ;8例自身抗体阴性而免疫球蛋白升高的其他疾病患者的强度为 5 8× 10 5~ 3 5× 10 7拷贝 /μgRNA ,均值为 (1 2±  相似文献   
82.
This is a study to define the profile of chemokine receptors expressed on isolated infiltrating lymphocytes in human abdominal aortic aneurysms (AAAs), and to examine their role in lymphoid recruitment. AAA T-lymphocytes were CXCR4-positive, CCR7-negative and partially CXCR3 and CCR5-positive. Functionally, AAA T-cells were proinflammatory effector cells, as they produced IFN-γ and granzyme A. AAA B-lymphocytes were CXCR4-positive and exhibited low CXCR5 expression. A relevant feature of infiltrating T- and B-lymphocytes was the high intensity of CXCR4 expression and the capability to migrate to CXCL12. CXCL12-producing cells were found in the adventitia of AAA. These cells were CD45-negative and partially VCAM-1 and DR-positive. In summary, the present results suggest that CXCR4, expressed on infiltrating lymphocytes, and CXCL12, expressed on stromal cells, is involved in the recruitment of lymphocytes within the arterial wall in AAA.  相似文献   
83.
《Pancreatology》2016,16(3):434-440
BackgroundRecently, several preoperative proinflammatory markers and nutritional factors such as neutrophil-to-lymphocyte ratio (NLR) and prognostic nutrition index (PNI) have been reported as significant predictor for poor prognosis of various malignant tumors. In this study, we evaluated the prognostic values of these preoperative parameters in patients with resectable pancreatic head cancer.MethodsWe retrospectively reviewed consecutive patients who underwent PD for pancreatic head cancer between 2007 and 2012. A total of 46 patients were enrolled in this analysis. Preoperative parameters such as CRP, CA19-9, NLR and PNI at the time of presentation were recorded as well as overall survival. Cancer specific survival was assessed using Kaplan–Meier method. Univariate and multivariate Cox regression models were applied to evaluate the prognostic relevance of preoperative parameters. The correlations between CA19-9 values, NLR and pathological findings, first recurrence site were respectively reviewed.ResultsIn multivariable analysis preoperative high NLR (≧2.7) and high CA19-9 (≧230) were independent prognostic factors for poor survival (P value: 0.03 and 0.025, respectively). Kaplan–Meier survival analysis demonstrated the overall 2-year survival rate in patients with high NLR or high CA19-9 were 37.5% compared with 89.9% in patients with low NLR and low CA19-9.ConclusionPreoperative NLR and serum CA19-9 offer significant prognostic information associated with overall survival following PD in the patients with pancreatic head cancer.  相似文献   
84.
Experimental autoimmune encephalomyelitis (EAE) is an animal model of human multiple sclerosis that requires the activation of autoreactive T cells for the expression of pathology. EAE has been most frequently studied in the Lewis rat model as well as in several murine models of EAE including the PLJ and B10PL strains. In the present study we describe a novel model of EAE induced in the Wistar rat strain by immunization with guinea pig spinal cord antigens and pertussis toxin (PT). T cell responses were induced to myelin basic protein. Autoreactive T cells could be totally blocked by the in vitro treatment with CTLA4Ig, a protein that blocks the costimulation of autoreactive T cells. The addition of IL-2 could reverse the inhibition seen in vitro with CTLA4Ig. The effects of inhibition of B7 costimulation were also examined by an analysis of cytokine responses and IL-2 receptor on T cells. CTLA4Ig treatment in vitro reduced the expression of IL-2 receptor on T cells, enhanced T cell apoptosis and decreased the synthesis of IL-2, IFN- &#110 and TNF- &#102 . CTLA4Ig treatment had no effect on IL-10 synthesis by T cells, a cytokine implicated in the functions of regulatory T cell subsets. Overall, our studies support the rationale of B7 blocking therapies as a potential treatment for models of multiple sclerosis. The induction of EAE in the Wistar rat provides yet another novel model in which to examine the regulation of T cell autoimmunity.  相似文献   
85.
Fas (CD95) and Fas ligand (FasL) are a receptor/ligand pair critically involved in lymphocyte homeostasis and peripheral tolerance such that genetic defect in either Fas or FasL results in an autoimmune lymphoproliferative syndrome. Fas is a type I transmembrane protein and a member of the tumor necrosis factor receptor (TNFR) family whereas FasL is a type II transmembrane protein and a member of TNF family. Binding of Fas by FasL induces apoptosis of the Fas-expressing cells. In the past few years. Fas/FasL interaction has been connected to a series of important phenomena previously viewed as independent immune processes. The activation-induced T cell death (AICD) and the FasL-mediated cytotoxicity by activated T cells are two critical mechanisms that can account for most of these phenomena. It is in the context of the two mechanisms that we discuss in this review the molecular and cellular events that occur during T/T and T/B interactions that account for the down-regulation of the immune response. We have also discussed recent advances in the areas of FasL gene regulation, lymphokine regulation of AICD, and regulation of B cell susceptibility to FasL. Investigation in these areas should help elucidate the role of Fas/FasL in the complex network of regulatory mechanisms that control immune response and autoimmunity.  相似文献   
86.
Today, almost three dozen human chemokines have been identified. The main function of these soluble proteins is the recruitment of leukocytes to sites of infection and inflammation. This review emphasizes the new developments in the field of lymphocyte responses to chemokines. Notably, it was shown that lymphocytes require stimulation to become responsive to chemokines, a process that is closely linked to chemokine receptor expression. As an exception, one chemokine, SDF-1, is a highly effective chemoattractant for non-activated T lymphocytes and progenitor B cells. Of particular interest are the chemokines IP10 and Mlg which bind to a receptor with selective expression in activated T lymphocytes and, therefore, may be critical mediators of T lymphocyte migration in T cell-dependent immune-responses. All other chemokines with activities in lymphocytes do also induce responses in monocytes and granulocytes. The involvement of chemokine receptors in HIV infection is briefly mentioned, while other interesting areas in chemokine research, such as hematopoiesis and angiogenesis, are not discussed.  相似文献   
87.
对 32例轻症和 44例重症婴幼儿肺炎检测外周血中可溶性白细胞介素 2受体 (s IL- 2 R)、白细胞介素 2膜受体 (m IL- 2 R)、T淋巴细胞亚群、血清 Ig、Ig A、Ig M和补体 C3的变化。结果 :重症婴幼儿肺炎 s IL- 2 R显著高于轻症婴幼儿肺炎 ,轻症高于对照组 (P<0 .0 5 ) ,而 m IL- 2 R则重症低于轻症、轻症低于对照组 (P<0 .0 5 ) ;婴幼儿肺炎 T细胞亚群 CD8显著低于对照组 (P<0 .0 5 ) ,CD4/ CD8高于对照组 (P<0 .0 5 ) ;Ig G、Ig A、Ig M和补体 C3重症低于轻症、轻症低于对照组 (P<0 .0 5 )。结果提示 s I1- 2 R和 m I1- 2 R表达异常和细胞免疫紊乱及体液免疫不足是婴幼儿肺炎的易患因素 ,且与病情严重程度有相关性。  相似文献   
88.
无复流(NR)指冠状动脉在解除机械性病变情况下心肌得不到有效灌注发生前向血流明显减慢的现象。且为急性ST段抬高型心肌梗死(STEMI)患者直接经皮冠状动脉介入治疗(PPCI)的严重并发症。全血细胞计数(CBC)是临床最常见的检测方法。以往大量研究已证实CBC对疾病严重程度、死亡风险及并发症发生的预测能力。因此,本文就CBC中红细胞、血小板、白细胞及血小板/淋巴细胞比值等对NR的研究进展进行阐述。  相似文献   
89.
背景:淋巴细胞功能相关抗原-1(LFA-1)参与T细胞的活化和功能调节,与炎症性肠病的发病密切相关。目的:观察LFA-1基因缺失(LFA-1-/-)对小鼠Nave T细胞体外向Th17细胞分化的影响。方法:繁殖LFA-1-/-子代小鼠,提取鼠尾DNA,PCR法鉴定基因型。LFA-1-/-子代小鼠为实验组,野生型(WT)C57BL/6J小鼠为对照组,磁珠分选脾脏单个核细胞中的CD4+CD62L+Nave T细胞并检测其纯度。体外建立不同Th17细胞诱导分化体系[转化生长因子-β(TGF-β)、TGF-β+白细胞介素-6(IL-6)和TGF-β+IL-6+IL-23],以流式细胞术检测两组分选得到的Nave T细胞在不同体系中诱导出的Th17细胞比率,荧光定量PCR法和ELISA法检测Th17细胞特异性转录因子ROR-γt和特异性标记物IL-17A表达。结果:15只子代小鼠均为LFA-1-/-小鼠,磁珠分选得到的CD4+CD62L+Nave T细胞纯度大于95%。低剂量TGF-β+IL-6即能诱导出Th17细胞,在此基础上加入IL-23能促进更多Th17细胞产生。与WT对照组相比,LFA-1-/-组Nave T细胞在TGF-β+IL-6+IL-23体系中诱导产生Th17细胞的效应更为明显(17.2%±1.4%对5.7%±0.2%,P0.001),ROR-γt、IL-17A mRNA表达上调(P0.001),细胞培养上清液中IL-17A浓度升高(P0.01)。结论:LFA-1基因缺失能促进小鼠Nave T细胞体外向Th17细胞分化。  相似文献   
90.
Lymphocyte adhesion and subsequent trafficking across endothelial barriers are essential steps in various immune‐mediated disorders of the CNS, including MS. The molecular mechanisms underlying these processes, however, are still unknown. Phospholipase D1 (PLD1), an enzyme that generates phosphatidic acid through hydrolysis of phosphatidylcholine and additionally yields choline as a product, has been described as regulator of the cell mobility. By using PLD1‐deficient mice, we investigated the functional significance of PLD1 for lymphocyte adhesion and migration in vitro and after myelin oligodendrocyte glycoprotein (MOG)35–55‐induced EAE, a model of human MS. The lack of PLD1 reduced chemokine‐mediated static adhesion of lymphocytes to the endothelial adhesion molecules vascular cell adhesion molecule 1 (VCAM‐1) and intercellular adhesion molecule 1 (ICAM‐1) in vitro, and was accompanied by a decreased migratory capacity in both blood brain barrier and cell migration models. Importantly, PLD1 is also relevant for the recruitment of immune cells into the CNS in vivo since disease severity after EAE was significantly attenuated in PLD1‐deficient mice. Furthermore, PLD1 expression could be detected on lymphocytes in MS patients. Our findings suggest a critical function of PLD1‐dependent intracellular signaling cascades in regulating lymphocyte trafficking during autoimmune CNS inflammation.  相似文献   
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