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181.
Sazuku Nisitani Takeshi Tsubata Masao Murakami Tasuku Honjo 《European journal of immunology》1995,25(11):3047-3052
Activation mechanisms of B-1 (Ly-1 B) cells have been suggested to be different from those of conventional B cells. To assess the role of various interleukins (IL) in the activation of B-1 cells, we injected IL-4, IL-5 or IL-10 into nonanemic anti-red blood cells (RBC) autoantibody-transgenic mice, in which conventional B cells are clonally deleted but peritoneal B-1 cells persist without secreting Ig. Intraperitoneal or intramuscular injection of IL-5 or IL-10, but not IL-4, increased the number of antibody-producing peritoneal B-1 cells by four- to five-fold, resulting in increased anti-RBC serum autoantibody and induction of hemolytic anemia. These results suggest that IL-5 or IL-10 may play an important role in the terminal differentiation of B-1 cells into antibody-producing cells in vivo. 相似文献
182.
Interleukin-11 expression: its significance in eutopic and ectopic human implantation 总被引:5,自引:0,他引:5
von Rango U Alfer J Kertschanska S Kemp B Müller-Newen G Heinrich PC Beier HM Classen-Linke I 《Molecular human reproduction》2004,10(11):783-792
Embryo implantation and subsequent decidualization, trophoblast invasion and formation of a functional placenta are crucial for establishment and maintenance of pregnancy. Interleukin-11 signalling has been shown to be obligatory for adequate decidualization and trophoblast invasion in mice. Defects in IL-11 signalling in mice result in trophoblast over-invasion and fetal loss. The pathological situation of human tubal pregnancy resembles that of IL-11Ralpha(-/-) mice concerning these symptoms. As our interest is focused on the human early pregnancy, we compared IL-11 expression at the implantation site of ectopic tubal pregnancy (EP) to 1st and 2nd trimester of normal intrauterine pregnancies (IP), and to the normal cycling endometrium. The mRNA expression of IL-11 and IL-11Ralpha was analysed by semiquantitative RT-PCR. Protein expression was detected by western blotting and immunohistochemistry. IL-11Ralpha is expressed constitutively in all tissue specimens analysed. IL-11 is expressed predominantly during follicular and early luteal phase of the menstrual cycle. In IP, IL-11 expression peaks during the 1st trimester and declines from the beginning of the 2nd trimester onwards. In tubal abortions, IL-11 expression is reduced in comparison to vital EP and IP. Cultured primary endometrial and decidual epithelial cells were analysed for hormonal regulation of IL-11 by enzyme-linked immunosorbent assay and RT-PCR. IL-11 is up-regulated by estrogen and down-regulated by progesterone. Overall, our results indicate that in humans, IL-11 signalling is significantly involved in regulation of trophoblast invasion. In the case of tubal abortion, inadequate IL-11 signalling may therefore result in dysregulation of trophoblast invasion. 相似文献
183.
Lisa T. Nelson Sabita Rakshit Hanshi Sun Deneen M. Wellik 《Developmental dynamics》2008,237(11):3410-3416
Hox genes are crucial for body axis specification during embryonic development. Hoxa11 plays a role in anteroposterior patterning of the axial skeleton, development of the urogenital tract of both sexes, and proximodistal patterning of the limbs. Hoxa11 expression is also observed in the neural tube. Herein, we report the generation of a Hoxa11eGFP targeted knock‐in allele in mice in which eGFP replaces the first coding exon of Hoxa11 as an in‐frame fusion. This allele closely recapitulates the reported mRNA expression patterns for Hoxa11. Hoxa11eGFP can be visualized in the tail, neural tube, limbs, kidneys, and reproductive tract of both sexes. Additionally, homozygous mutants recapitulate reported phenotypes for Hoxa11 loss of function mice, exhibiting loss of fertility in both males and females. This targeted mouse line will prove useful as a vital marker for Hoxa11 protein localization during control (heterozygous) or mutant organogenesis. Developmental Dynamics 237:3410–3416, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
184.
血管内皮细胞衬于血管腔的表面,是血流机械应力的主要感受者。切应力可以直接调节内皮细胞生物活性物质的合成和分泌,其中包括诱导内皮细胞生成IL-8,而且IL-8的生成量与切应力作用时间有关。为阐明内皮细胞IL-8的生成除了与切应力的作用时间有关外还与切应力的强度有关,我们用不同强度的流体切应力(2.09、4.61、6.19、8.51、10.50、12.59、14.41、17.22、18.32dyne/cm^2)处理培养的人脐静脉内皮细胞,然后采用双抗体夹心ABC-ELISA技术检测内皮细胞IL-8蛋白质的生成。结果显示:未用切应力处理的内皮细胞只有极少量的IL-8蛋白质生成;切应力处理内皮细胞后,低切应力(2.09dyne/cm^2)时IL-8蛋白质生成量明显增加,约为高切应力(18.32dyne/cm^2)时IL-8蛋白质生成量的6(作用5h)或7倍(作用6h)。IL-8蛋白质生成量与内皮细胞所施加的切应力强度呈反变关系;直线回归方程:5h时为y=760.12—36.06x,相关系数7=-O.978;6h时为y=781.87—36.66x,相关系数7=-O.980。式中:y为切应力作用下内皮细胞IL-8的生成量;x为施加于内皮细胞的切应力强度(dyne/cm^2)。不同的切应力作用时间(5h、6h)均表现出相同的IL-8蛋白质生成量随切应力强度的变化规律。提示流体切应力诱导内皮细胞生成IL-8的量,不仅与切应力的作用时间有关,而且IL-8的生成量与切应力强度有关。流体低切应力诱导内皮细胞IL-8的生成量急剧增高,可能在急性炎症和动脉粥样硬化的发生、发展过程中具有重要作用。 相似文献
185.
分别用ELISA、IRMA法对50例支气管哮喘急性发作患者和48名对照者血清IL-10、IgE进行测定.结果是: 支气管哮喘患者IL-10含量明显低于对照组(P<0.01), 而IgE含量则明显高于对照组(P<0.01), 两者之间呈明显负相关(r=-0.18,P<0.01).结论是: 支气管哮喘患者IL-10不足、IgE水平增高可能成为其发病的重要原因之一. 相似文献
186.
Peter G. Tipping A. Richard Kitching Xiao Ru Huang David A. Mutch Stephen R. Holdsworth 《European journal of immunology》1997,27(2):530-537
Crescentic glomerulonephritis (GN) demonstrates immunopathological features of a T helper (Th)1-directed delayed-type hypersensitivity (DTH) response. The capacity of Th2 cytokines to attenuate crescentic glomerular injury in this disease was examined by administering interleukin (IL)-4 and IL-10, singly and in combination. GN was induced by i.v. administration of sheep anti-mouse glomerular basement membrane (GBM) globulin to mice sensitized to sheep globulin 10 days earlier. Treatment (2.5 μg, i.p.) with IL-4, IL-10, or both IL-4 and IL-10 (IL-4+10), was started 1 h before sensitization and continued daily until the end of the study (10 days after administration of anti-GBM globulin). Control mice treated with PBS developed GN with glomerular accumulation of T cells and macrophages, crescents in 42.5 ± 4.5 % of glomeruli (normal 0 %), proteinuria (8.3 ± 0.9 mg/24 h, normal 0.74 ± 0.08 mg/24 h, p < 0.001) and renal impairment (creatinine clearance [cr/cl]: 93 ± 12 μ1/min, normal 193 ± 10 μ1/min, p<0.001). 1reatment with either IL-4, IL-10, or IL-4+10 prevented crescent formation (crescentic glomeruli: 0.8 ± 0.5, 1.2 ± 0.9, and 1.4 ± 1.0 %, respectively, all p<0.01 compared to control) and attenuated proteinuria (3.6 ± 1.0, 2.2 ± 0.5, and 2.9 ± 0.5 mg/24 h, respectively, all p<0.01 compared to control). IL-4+10 prevented development of renal impairment (cr/cl: 183 ± 22 μ1/min); IL-10 given alone limited the decline in renal function (cr/cl: 150 ± 20 μ1/min), but IL-4 alone did not provide any significant protection (cr/cl: 121 ± 17 μ1/min). All treatments markedly diminished glomerular T cell and macrophage accumulation, reduced interferon-γ production by splenic T cells, prevented cutaneous DTH to the disease-initiating antigen and reduced antigen-specific immunoglobulin of the IgG2a and IgG3 isotypes. These data demonstrate that crescentic GN and renal impairment can be prevented by administration of Th2 cytokines and that this effect is associated with attenuation of the Th1 response to the disease-initiating antigen. 相似文献
187.
Cornelis G. Olthof Johanna W. Baars John Wagstaff Ab J. M. Donker Hans Schneider Peter M. J. M. de Vries 《European journal of applied physiology》1993,67(2):168-173
Summary One of the most common side effects of treatment with recombinant interleukin-2 (IL-2) is capillary leakage. Its genesis is not completely understood. The aim of the study was to determine whether capillary leakage can be monitored by means of a non-invasive conductivity technique and to study its starting point. Eight patients with advanced renal cell cancer were studied in a medium care section of the Department of Medical Oncology, University Hospital over 4 days during treatment sessions of continuous, intravenously administered IL-2 (mean dose of 15.6 × 106 IU · m–2 · day –1). The fluid shift from the intravascular to the extra- and intracellular compartments was monitored by means of noninvasive conductivity measurements. Changes in blood volume were calculated from serial erythrocyte counts. The clinical parameters of capillary leakage (oliguria, positive fluid balance, and gain in mass) were recorded. The mean gain in mass was 9% after 4 days of IL-2 treatment. The extracellular fluid volume increased significantly [46 (SD 23.2)%; P < 0.01], whereas the intracellular fluid volume did not change. The increase in blood volume (BV) amounted to 7% (P < 0.05). The decline in albumin concentration was significantly more than the increase in BV [38 (SD 4.3) %; P < 0.01], indicating capillary albumin leakage. The main changes were observed after the 2nd day of treatment. From this study, it is suggested that conductivity measurements are a suitable method to monitor capillary leakage induced by IL-2, and could be used to detect the exact onset and severity of this leakage. The leakage started within the first 24 h of treatment and was detected as a fluid shift from the intravascular to the extracellular space, while the intracellular compartment remained stable. These measurements could be useful during intervention studies with the aim of preventing this adverse effect of IL-2. 相似文献
188.
目的:探讨白细胞介素13(IL-13)对体外培养的大鼠系膜细胞的增殖及其产生白细胞介素6(IL-6)的影响。方法:用四甲基偶氮唑(MTT)法测定系膜细胞增殖,用逆转录聚合酶链反应(RT-PCR)及酶联免疫吸附法(ELISA)测定系膜细胞IL-6mRNA表达及其蛋白水平。结果:IL-13在1、10、100μg/L浓度范围呈剂量依赖性地抑制系膜细胞的增殖;5%FCSRPMI1640培养条件下系膜细胞IL-6mRNA表达及IL-6分泌水平较低,脂多糖(LPS)可刺激系膜细胞IL-6mRNA的表达及提高IL-6分泌水平,而IL-13可抑制LPS诱导的系膜细胞IL-6分泌及其mRNA表达。结论:IL-13抑制体外培养的系膜细胞增殖及LPS诱导的系膜细胞IL-6的产生,IL-13可能对于肾小球肾炎的系膜细胞炎症反应具有拮抗作用。 相似文献
189.
目的 筛选和鉴定人乳头状瘤病毒11型E7抗原(HPVllE7)HLA-A*0201限制性细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL)表位.方法 预测HPVllE7抗原HLA-A*0201限制性CTL表位并合成相对应的表位多肽和四聚体(tetramer),即HPVllE7 7-15(TLKDIVLDL)、15-23(LQPPDPVGL)、47-55(PLTQHYQIL)、81-89(DLLLGTLNI)和82-90(LLLGTLNIV).从健康HLA-A*0201成人外周血单一核细胞诱导树突状细胞(DC)并负载上述表位多肽,流式细胞技术检测DC成熟分化标记及ELISA法检测DC分泌的IL-12;成熟DC负载各组多肽后观察DC激活T淋巴细胞的效应,ELISA法检测T细胞分泌的IFN-γ;四聚体检测抗原特异性CD8+ T细胞及乳酸脱氢酶(LDH)释放法评价DC诱导的CTL对靶细胞的特异性体外杀伤效应.结果 预测的5条HPVllE7表位多肽均能诱导DC的成熟分化;E7 7-15、82-90和15-23多肽负载的DC能激活T淋巴细胞分泌高水平IFN-γ;E7 7-15多肽负载的DC能刺激特异性tetramer+CD8+细胞增殖且其诱导的CTL对HPVllE7/293细胞产生高效率的特异性杀伤作用(P<0.05).结论 筛选并鉴定出1条HPVllE7HLA-A*0201限制性CTL表位E7 7-15(TLKDIVLDL),负载该表位肽的DC体外可诱导高效、特异性的CTL效应,抗原性较强,有可能作为HPV感染治疗用肽疫苗的候选表位. 相似文献
190.
目的探讨醛固酮合成酶(CYB11B2)基因多态性与怀化侗族高血压高发人群原发性高血压(EH)及血脂水平的关系.方法采用聚合酶链反应结合限制性内切酶片段长度多态分析方法(PCR-RFLP)检测89例怀化侗族高血压病人和85例正常人的CYB11B2-344C/T等位基因频率和基因型频率.结果高血压组CYB11B2-344C/T基因型频率(CC 10.1%、CT41.6%、TT 48.3%)和等位基因频率(C 30.9%、T 69.1%)与正常对照组基因型频率(CC 10.3%、CT 27.6%、TT 62.1%)和等位基因频率(C 24.1%、T 75.9%)比较无显著性差异.CC基因型患者与CT TT基因型患者比较,收缩压和舒张压无显著性差异.结论怀化侗族人群EH可能与CYB11B2基因多态性无关. 相似文献