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81.
卵巢癌细胞多种细胞因子基因表达的研究 总被引:1,自引:0,他引:1
本文应用RT-PCR方法,检测5例刚分离的晚期上皮性卵巢癌患者肿瘤细胞和3例卵巢痛患者腹水中肿瘤细胞IL-2、IL-2R、TNF-a,IL-6、TGF-p、IL-10等细胞因子基因的表达,用免疫学方法检测卵巢癌细胞上清液中IL-6活性。结果发现:卵巢癌肿瘤细胞表达IL-6mRNA和抑制性细胞因子TGF-p、IL-10。腹水中存在较多量lL-6可能来自肿瘤细胞。 相似文献
82.
L. M. TERAN M. G. CAMPOS B. T. BEGISHVILLI J.-M. SCHRÖDER R. DJUKANOVIC J. K. SHUTE M. K. CHURCH S. T. HOLGATE D. E. DAVIES† 《Clinical and experimental allergy》1997,27(4):396-405
Background Although neutrophils have been implicated in bronchial asthma, the mechanism(s) which bring these cells into the airways is poorly understood. Objective To investigate the presence and identity of neutrophil chemotactic factors in bronchoalveolar lavage (BAL) fluid from atopic asthmatic subjects. Method BAL fluid was obtained from 13 subjects (seven asthmatics and six normals). aged 19 to 60 yr, at bronchoscopy. Separation of neutrophil chemotactic activity (NCA) was achieved by FPLC cation exchange chromatography. Fractions were collected and assayed for chemotaxis multiwell micro-chemotaxes chambers using polycarbonate filters, for the complement peptide C5a/C5a des Arg by radioimmunoassay (RIA) and for interleukin-8 (IL-8) by ELISA. Results NCA was found in FPLC fractions of BAL samples in four out of seven asthmatics and each of these subjects had at least three similar peaks of NCA. The major peak of NCA was found to contain immunoreactive C5a/C5a des Arg and chemotaxis. In response to this NCA could be blocked by desensitization of the neutrophils with recombinant C5a. Purified serum derived C5a/C5a des Arg was found to have altered chromatographic properties when added to BAL fluid; this suggested that BAL fluid contained proteins which interacted with the C5a/C5a des Arg. Immunoreactive IL-8 (iIL-8) was also detected but its concentration or chemical form was insufficient to induce neutropbil chemotaxis. Conclusion This study demonstrates that bronchial asthmatic lavage fluid contains C5a/C5a des/Arg and iL-8, together with other as yet unidentified factors which may contribute to neutropbil recruitment in this disease. 相似文献
83.
BACKGROUND: We have previously demonstrated that the proteolytic activity of Der p 1 selectively cleaves human CD25, the 55 kDa alpha subunit of the IL-2 receptor. As a result of cleavage of surface CD25, peripheral blood T cells produce less IFN-gamma and more IL-4, thereby leading to progressive polarization of the T cells towards a Th2 cytokine profile. Therefore, these observations underline the potential role of the proteolytic activity of Der p 1 in creating a microenvironment conducive for IgE synthesis. OBJECTIVE: To study the effect of T cells that have been conditioned by the proteolytic activity of Der p 1 on IgE synthesis by B cells. METHODS: We have examined this concept in experiments whereby T cells that have been exposed to either proteolytically active or inactive Der p 1 were cocultured with autologous B cells and IgE antibody synthesis was monitored. RESULTS: Here we demonstrate for the first time that coculturing T cells that have been in contact with proteolytically active Der p 1 with autologous B cells leads to augmentation of IgE antibody responses. CONCLUSIONS: The proteolytic activity of Der p 1 conditions human T cells, which then become empowered to trigger enhanced IgE synthesis by B cells. 相似文献
84.
E. Johansson S. Mnsson R. Wirestam J. Svensson J.S. Petersson K. Golman F. Sthlberg 《Magnetic resonance in medicine》2004,51(3):464-472
Cerebral perfusion was assessed with 13C MRI in a rat model after intravenous injections of the 13C-labeled compound bis-1,1-(hydroxymethyl)-1-13C-cyclopropane-D8 in aqueous solutions hyperpolarized by dynamic nuclear polarization (DNP). Since the tracer acted as a direct signal source, several of the problems associated with techniques based on traditional dynamic susceptibility contrast (DSC) MRI contrast agents were avoided. Maps of cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) were calculated. The MTT was determined to be 2.8 +/- 0.8 sec. However, arterial partial-volume effects in the animal model prevented accurate absolute quantification of CBF and CBV. It was demonstrated that depolarization of the hyperpolarized 13C tracer via relaxation and the imaging sequence had little influence on CBF assessment when the time resolution of the imaging sequence was short compared to the MTT. However, CBV and MTT were increasingly underestimated as MTT or the depolarization rate increased if depolarization was not taken into account. With a modified bolus-tracking theory depolarization could be compensated for, assuming that the depolarization rate was known. Three separate compensation methods were investigated experimentally and by numerical simulations. 相似文献
85.
目的:观察中药肾康宁对家兔实验性肾炎黏附分子及细胞因子表达的影响,以及临床肾小球肾炎治疗前后尿蛋白的变化.方法:检测牛血清白蛋白所致急性实验性肾炎动物肾组织ICAM-1表达、血清IL-6水平的变化,以及临床肾小球肾炎肾康宁治疗前后血清IL-6水平、尿蛋白的变化.结果:肾康宁能明显降低实验动物血清IL-6含量,降低急性实验性肾炎模型中ICAM-1阳性细胞表达率,同时减轻肾小球基底膜(GBM)增厚及炎症细胞浸润,阻止毛细血管内微血栓的形成;在临床肾小球肾炎中,肾康宁能减少肾小球肾炎患者血清IL-6水平及24 h尿蛋白含量.结论:肾康宁通过降低细胞因子IL-6水平和黏附分子ICAM-1的表达,从而抑制免疫细胞的趋化、浸润、活化和增殖、减少免疫复合物的沉积,使肾小球炎症反应减轻,有效缓解家兔急性实验性和临床肾小球肾炎,使肾功能得以改善. 相似文献
86.
Jae Sue Choi Han Suk Young Jong Cheol Park Jin-Ho Choi Won Sick Woo 《Archives of pharmacal research》1986,9(4):233-236
The flavonoids isolated from the leaves ofRhododendron brachycarpum, were identified as quercetin, avicularin, quercitrin and hyperin. 相似文献
87.
88.
Ultraviolet radiation (UVB) in sunlight is known to have multiple effects on the immune system. Evidence suggests that UVB-induced immunosuppression is mediated in part by immunosuppressive and immunoregulatory cytokines. Our studies have utilized gene-targeted mutant mice to determine key molecular requirements essential for the development of UVB-induced immunosuppression. Preliminary results from our laboratory suggest that TNF-α plays a regulatory role in contact hypersensitivity, but is not a crucial factor for UVB-induced immunosuppression, and that multiple factors are involved in the induction of UVB mediated immunosuppression. 相似文献
89.
Inhibition of tissue factor surface expression in human peripheral blood monocytes exposed to cytokines 总被引:1,自引:0,他引:1
Interleukin (IL)-4, IL-10, IL-13 and transforming growth factor beta (TGF-β) are known to regulate several monocyte functions, including inhibition of the synthesis of different cytokines. Using quantitative RT-PCR and flow cytometry analysis we investigated the effects of these cytokines on bacterial lipopolysaccharide (LPS)-induced tissue factor (TF) expression in human monocytes. The effects of IL-4 and IL-10 on monocyte chemoattractant protein-1 (MCP-1)- and C-reactive protein (CRP)-induced TF expression were also studied. A direct comparison revealed that IL-4, IL-10 and IL-13 all down-regulated LPS-induced TF expression in a concentration-dependent manner without the need for priming. In contrast, TGF-β required 4 h of priming to inhibit TF expression induced by LPS. IL-10 was the most powerful inhibitor, causing almost complete inhibition at 5 ng/ml. IL-4 and IL-13 exhibited a significantly lower inhibitory capacity even at concentrations of 100 ng/ml. IL-4 and IL-10 showed similar concentration-dependent inhibition of MCP-1- and CRP-induced TF expression. We also showed that the regulatory effect of the interleukins occurred at the mRNA level. In vivo , these inhibitory cytokines may play an important regulatory role in preventing thrombosis. IL-10, in particular, may be a possible candidate as a TF-preventing drug. 相似文献
90.
Substance P (SP) is a tachykinin involved in the regulation of inflammatory processes. To investigate a modulatory role of the neuropeptide SP in allergic inflammation, we studied its priming effect on human eosinophil chemotaxis and kinetic responses towards platelet activating factor (PAF) and recombinant human interleukin 5 (rhlL-5). Blood was obtained from normal subjects and eosinophils were separated by Percoll discontinuous density gradient centrifugation. High purification was obtained by negative selection procedure (CD16-beads) and the experiments were performed in a 48-well microchemotaxis Boyden chamber. In the present study we demonstrate a potent synergistic effect of 100nM dose of SP on the migratory function of human eosinophils stimulated by PAF and rhIL-5. This synergism was chemotaxis specific and was abolished by NK-1 receptor antagonist (FK888). The results suggest that neurogenic stimuli may play a significant role in eosinophil infiltration via its priming effect on the cell. 相似文献