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51.
Idziorek Khalife Billaut-Mulot Hermann Aumercier Mouton Capron Bahr 《Clinical and experimental immunology》1998,112(1):84-91
The chemoattractant cytokine IL-16 has been reported to suppress lymphocyte activation and to inhibit HIV-1 replication in acutely infected T cells. We have cloned and expressed human IL-16 in Escherichia coli and investigated whether the recombinant protein could regulate the level of lymphocyte apoptosis from HIV-1-infected subjects. After purification and refolding, only 2–10% of the recombinant cytokine was present in a biologically active homotetrameric form. This could explain the need for high concentrations of the bacterially derived IL-16 to induce significant inhibition of HIV-1 replication. Addition of IL-16 to unstimulated peripheral blood mononuclear cell (PBMC) cultures from HIV-1-infected subjects did not modify the observed level of spontaneous lymphocyte apoptosis. In contrast, IL-16 added to PBMC cultures stimulated with anti-CD3, anti-CD95 or dexamethasone reduced significantly the percentage of lymphocytes undergoing AICD. This effect was found to correlate with the ability of the cytokine to decrease CD95 expression on activated CD4+ T cells. Comparative studies on PBMC from healthy individuals indicated that the regulation of apoptosis levels by IL-16 is a complex phenomenon and could depend on the nature of the activator used and/or the immune status of lymphocytes tested. The outcome of CD4 cross-linking on T cells by various ligands is discussed in the context of the observed beneficial activities of IL-16 and its potential role in the treatment of HIV disease. 相似文献
52.
53.
Zhang Gui-mei Hao Tian-ling Yang Yu-zhen Feng Zuo-hua Jiang Zhi-yao Zhou Bin Zhang Hui 《华中科技大学学报(医学英德文版)》1992,12(3):150-153
Summary Effects of Chinese Medicinal Preparation “Re Du Qing” (RDQ) on the activation, proliferation and membrane fluidity of T lymphocytes
from human peripheral blood Were studied by means of3H-TdR incorporation and DPH fluorescence polarization. The results showed that “RDQ” can:1) significantly inhibit the activation
of T lymphocytes; 2) restrain the proliferation of activated T lymphoblasts in the presence of exogenous interleukin-2 (IL-2);
and 3) increase the membrane fluidity of T lymphocytes and antagonize the decreased fluidity of lymphocyte membrane mediated
by Con A or PHA. The functional abnormalities of T lymphocytes in some autoimmune diseases such as arthritis and the usefulness
of RDQ in the treatment of these diseases were also discussed. 相似文献
54.
Modulation of human T cell functions by surface sulphydryl groups: differential effects on IL-2 production and responsiveness.
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An impermeable thiol blocker has been used to investigate the role of sulphydryl (SH) groups in the production of and responsiveness to IL-2 by normal human T lymphocytes. Surface SH blockade of mononuclear cells prior to incubation with mitogen (phytohaemagglutinin, concanavalin A, CD3 MoAb) had no effect on production of IL-2 but markedly impaired cellular responsiveness to exogenous IL-2. Studies using MoAbs indicated that this effect was accompanied by decreased expression of both the CD25 and p75 subunits of the IL-2 receptor. Blocking surface SH groups did not affect binding of IL-2 to p75 on unstimulated mononuclear cells, but inhibited binding to high-affinity receptors on a T lymphoma cell line. The data are consistent with the hypothesis that sulphydryl groups on the IL-2 receptor are required for its function and may be involved in the interaction of the CD25 and p75 subunits leading to generation of the high-affinity binding site. The surface thiol identified on the IL-2 receptor may be a candidate for oxidation on cells from patients with chronic inflammatory diseases such as rheumatoid arthritis and thus contribute to the aberrant function of T cells in these patients. 相似文献
55.
目的:探讨白细胞介素6(IL-6)、白细胞介素8(IL-8)与子宫内膜异位症(endomotriosisEMs)卵巢癌的发生发展关系。方法:采用双抗体夹心ABC-酶联免疫吸附实验(ELISA)对EMs患者30例、血清及腹腔液中IL-6、IL-8进行检测,并以卵巢癌患者10例、卵巢良性肿瘤患者30例、正常妇女血清30例做对照组。结果:EMs组与卵巢癌组患者血清及腹腔液中IL-6、IL-8水平明显高于对照组(P<0.01),EMs组与卵巢癌组对比无显著性差异(P>0.05)。结论:EMs患者腹腔液中IL-6、IL-8异常增高是腹腔免疫内环境失衡,与EMs的发生发展有关,在药物治疗中血清IL-6、IL-8可作为EMs疗效和预后的指标之一。 相似文献
56.
目的 观察逆转录病毒转病毒白细胞介素 10 (vIL 10 )基因在体内的表达。方法 用MSCVneo vIL 10重组体在体外转导CBA (H 2 K)小鼠的造血干细胞 (HSCs) ,给经致死照射(90 0rads)的 2 0只同基因CBA(H 2 K)小鼠注入经MSCVneo vIL 10转染的HSCs ,2× 10 6HSCs/只。酶联免疫吸附测定 (ELISA)、逆转录 聚合酶链反应 (RT PCR )、Westernblot分析vIL 10的表达。结果 移植MSCVneo vIL 10转染HSCs的 2 0只小鼠 ,移植后 8周用ELISA检测 ,其中 15只小鼠血清的vIL 10浓度为 :2 70~ 13 40ng/L ,5只小鼠血清的vIL 10为阴性。 12周后有 2只小鼠vIL 10测不出 ,13只小鼠长时间表达vIL 10达 6个月。对照组小鼠血清vIL 10均为阴性。RT PCR和Westernblot证实小鼠的器官均有vIL 10的mRNA和蛋白的表达。结论 逆转录病毒能有效地将vIL 10基因导入造血干细胞并在体内长时间表达。 相似文献
57.
IL-2在移植免疫中的研究进展 总被引:3,自引:0,他引:3
随着器官移植手术技术的逐渐成熟,移植后免疫排斥反应已成为制约器官移植的瓶颈。IL-2在免疫系统中起着关键作用,而且与免疫排斥和免疫耐受关系密切,因此,更好的理解 IL-2在免疫和自身耐受中的生理作用,对临床治疗中控制IL-2信号,获得更好治疗效果有指导意义。 相似文献
58.
目的 近年研究表明Rab11鸟苷三磷酸酶在调节各种真核细胞的膜转运通道中发挥着重要作用。但是,对于原生动物毛滴虫膜转运系统的研究仍甚少。本研究旨在克隆和分析阴道毛滴虫Rabll鸟苷三磷酸酶基因,以便进一步探讨其功能。方法 使用SMART cDNA文库构建试剂盒构建阴道毛滴虫cDNA表达文库,用生物信息学进行TvRab11同源分析,鉴定TvRab11基因,用PCR方法扩增基因组DNA,TA克隆TvRab11 cDNA、测序及序列分析。结果 在分离出的cDNA克隆中发现一个Rab11鸟苷三磷酸酶同源基因。该cDNA序列长710bp,读码框含636bp,推测蛋白质序列具211个氨基酸。序列分析表明该基因系Rab11亚家族的同源基因,其推测肽链与拟南芥Rab11c的同源性晟高(一致性60%,相似性79%),与人类Rab11b次之(一致性58%,相似性78%)。该氨基酸序列拥有Rab鸟苷三磷酸酶家族的所有保守结构域和特异性Rab结构域(RabF1-5)。进化树分析也表明该基因系Rab11的同源基因。序列分析还显示该基因的基因组DNA序列与cDNA序列完全一致.提示该基因无内含子。结论分析表明该基因是阴道毛滴虫Rab11鸟苷三磷酸酶同源基因,其功能有待进一步研究。 相似文献
59.
目的:探讨IL-6对人精子顶体反应(AR)的影响机制。方法:采用BAEE/ADH法测定精子顶体酶的活性,以及通过FITC-PSA法检测精子顶体反应。结果:IL-6可诱导精子顶体酶及超氧化物歧化酶(SOD)的活性,促进精子顶体反应;胞外Ca2+单独不能诱导精子顶体反应,且没有胞外Ca2+的参与,IL-6也不能诱导精子顶体反应;蛋白激酶C(PKC)抑制剂calphC能逆转IL-6诱导的精子顶体反应。结论:IL-6对精子顶体反应有一定的促进作用,可能通过诱导精子的顶体酶和SOD活性等途径来实现,在此作用中,也涉及了PKC的激活,且还需要外源性Ca2+的参与。 相似文献
60.
Abstract In inflammatory dermatoses. activated T cells produce inter-feron-gamma (IFN-γ), which interacts with keratinocytes and contributes to the direct activation of these cells by inducing, among other factors, the expression of HLA-DR antigens and intercellular adhesion molecule-1. However, the action of IFN-γ on epidermal cell cytokine production is not known. Our aim was to assess the effect of IFN-γ on the production of IL-1 by normal human keratinocytes cultured in low calcium medium (MCDB153). In comparison with controls, the addition of nontoxic IFN-yγ concentrations (50-500 U/ml) to cell cultures induced a significant increase of IL-1α and IL-1β production predominantly after 100 U/ml treatment in the cell extracts as well as in the supernatants at 24h and 48h. The production of the antagonist. IL-1RA, was also enhanced and the effect of the critical concentration (100 U/ml) was more evident. However, the absence of a characteristic dose response could not be explained by an antiproliferative effect of high IFN-γ concentrations (250 and 500 U/ml) on cultured keratinocytes or by the induction of the nuclear stress protein, Hsp72. two phenomena known to down-regulate IL-1 biosynthesis. In conclusion, the modifications in keratinocyte IL-1 production under IFN-γ stimulation can contribute to activate the epidermal cells and thus involve them in the local immune response. 相似文献