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61.
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
62.
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
63.
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
64.
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
65.
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
66.
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
67.
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
68.
Tatsuya Okimoto Hiroshi Yahata Yasuhiko Fukuda Keisuke Hayamizu Kiyohiko Dohi 《Transplant international》1994,7(S1):629-633
Abstract A study was conducted to elucidate the mechanism of donor-pecific Mixed Lymphocyte Reaction (MLR and Cell Mediated Lymphotoxicity (CML) unresponsiveness in a renal transplant recipient with a long-term well-functioning kidney. The peripheral blood lymphocytes (PBL) of the recipient, who had not shown rejection since his transplantation 5 years previously, and those of his mother (donor), his father and two healthy third parties were examined. MLR, CML, semimicro MLR in a double chamber, interleukin-2 (IL-2) synthesis assay and limiting dilution assay were performed. This recipient showed donor-pecific MLR and CML unresponsiveness. IL-2 assay showed that the PBL of the recipient produced less IL-2 against the donor than against the father and the third parties. The addition of exogenous recombinant IL-2 (rIL-2; Takeda Co.) to the priming MLR caused a recovery of CML against the donor. A limiting dilution assay indicated that cytotoxic T cell precursor (CTLp) frequencies against the donor and father did not differ. The suppressor assay in a double chamber indicated that the PBL of the recipient stimulated by the donor PBL had a non-pecific suppressive effect on MLR, CML and IL-2 synthesis of the PBL across the Major Histocompatibility Complex (MHC) barrier. This suppressive effect was abolished by OKT3 or OKT8 monoclonal antibody and complement. Thus, the recipient had donor-pecific suppressor T cells that produced a humoral non-pecific suppressive factor only when stimulated by the donor PBL, and this factor suppressed PLR and CML by inhibiting IL-2 synthesis of the PBL. 相似文献
69.
R. D. Myers F. J. Lopez-Valpuesta F. J. Minano M. H. Wooten V. S. Barwick S. D. Wolpe 《Journal of neuroscience research》1994,39(1):31-37
The chemokines, macrophage inflammatory protein-1 (MIP-1) and its subunit MIP-1β, induce an intense fever in the rat when they are injected directly into the anterior hypothalamic, pre-optic area (AH/POA), a region containing thermosensitive neurons. The purpose of this study was to compare the central action on body temperature (Tb) of MIP-1β with that of interleukin-6 (IL-6), which also has been implicated in the cerebral mechanism underlying the pathogenesis of fever. Following the stereotaxic implantation in the AH/POA of guide cannulae for repeated micro-injections, radio transmitters which monitor Tb continuously were inserted intraperitoneally in each of 15 male Sprague-Dawley rats. Each micro-injection was made in a site in the AH/POA in a volume of 1.0 μl of pyrogen-free artificial CSF, recombinant murine MIP-1β, or recombinant human IL-6. MIP-1β in a dose of 25 pg evoked an intense fever characterized by a short latency, a mean maximum rise in Tb of 2.4 ± 0.21°C reached by 3.7 ± 0.42 hr, and a duration exceeding 6.5 hr. Injected into homologous sites in the AH/POA, IL-6 induced a dose dependent fever of similar latency and a mean maximal increase in Tb of 1.2 ± 0.25°C, 1.8 ± 0.15°C, and 2.1 ± 0.22°C and duration of 6.2 ± 1.28 hr, 6.7 ± 0.49 hr, and 6.8 ± 0.65 hr when given in doses of 25, 50, and 100 ng, respectively. These results show that MIP-1β and the highest dose of IL-6 induce a fever of comparable intensity, but MIP-1β exerts its action in a much lower concentration. Thus, the de novo synthesis and subsequent action of the MIP-1 family of cytokines on neurons of the AH/POA in response to a pyrogen challenge apparently play a functional role in the pathogenesis of fever. Further, the endogenous activity of IL-6 in the hypothalamus which is enhanced in response to a lipopolysaccharide also may reflect its essential part in the acute phase response to a bacterial challenge. Copyright © 1994 Wiley-Liss, Inc. 相似文献
70.
胃癌患者红细胞免疫功能的变化 总被引:4,自引:1,他引:3
运用简单形态学方法测定了30例胃癌患者红细胞免疫功能,结果表明:胃癌患者红细胞C3b受体花环率及肿瘤红细胞花环率显著低于正常对照(P<0.01)及慢性良性胃病患者(P<0.01),而免疫复合物花环率则高于正常人(P<0.01)及慢性良性胃病患者(P<0.01);Ⅲ、Ⅳ期胃癌患者肿瘤红细胞复合物花环率明于低于Ⅰ、Ⅱ期患者(P<0.01);贲门癌肿瘤红细胞花环率显著低于胃窦(体)癌患者(P<0.01) 相似文献