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51.
I. Ibarrola M. L. Sanz† P. M. Gamboa‡ A. Mir§ D. Benahmed§ A. Ferrer¶ M. C. Arilla A. Martínez J. A. Asturias 《Clinical and experimental allergy》2004,34(2):303-309
BACKGROUND: Allergoids are widely used in specific immunotherapy (SIT) for the treatment of IgE-mediated allergic diseases, but all techniques for standardization of conventional allergic extracts may not be appropriate for standardization of a glutaraldehyde (GA)-modified extract because of the unique characteristics of these extracts. OBJECTIVE: To assess an accurate methodology for standardization of chemically modified extracts. METHODS: GA-modified extracts from Parietaria judaica pollen were purified by diafiltration. Biochemical properties were investigated by determination of amino groups, chromatography, and SDS-PAGE. The IgE-binding activity was determined by skin prick test, enzyme allergosorbent test inhibition, basophil activation, and histamine release tests. Peripheral blood mononuclear cells (PBMCs) from P. judaica pollen-allergic subjects were stimulated with either native or allergoid extracts, and proliferation was measured. RESULTS: Biochemical data indicated a high degree of allergen polymerization resulting in extract components higher than 100 kDa. IgE-binding activity, both in vivo and in vitro, was reduced by more than 99.8%. Both allergen and allergoid induced PBMC proliferation and synthesis of blocking IgG antibodies at similar rates. Moreover, no evidence of introduction of new determinants by chemical modification was found. CONCLUSIONS: The preparation of GA-modified extracts by diafiltration is faster and more reliable than previous chromatographic methods. These modified extracts have drastically reduced their allergenicity while maintaining their immunogenicity, and therefore they can be used in safer and shortened schedules of SIT. 相似文献
52.
目的探讨经门静脉注射药物治疗慢性乙型肝炎的可行性,观察门静脉置管注射中西药对慢性乙型肝炎患者细胞免疫功能的影响。方法8例肝癌术后的慢性乙型肝炎患者,于肝癌手术时皮下埋置药盒门静脉内置管,向药盒内注入胸腺肽40mg,黄芪注射液10ml。治疗前后用流式细胞术绝对计数T淋巴细胞及其亚群、自然杀伤细胞(NK),并观察其副反应。结果治疗前后CD3665.63±434.80个/μlvs1326.50±551.09个/μl,CD3 CD8 275.63±205.78个/μlvs513.50±231.00个/μl,CD3 CD4 515.88±329.75个/μlvs981.75±478.54个/μl,NK细胞130.86±176.58个/μlvs303.43±190.90个/μl,差异具有显著性意义(P<0.05),除1例中度发热、4例轻度发热外,无其他副反应。结论胸腺肽与黄芪合用可增强慢性乙肝患者的细胞免疫功能。经门脉注射药物可能成为乙肝治疗的新途径,应加大样本进一步研究。 相似文献
53.
用免疫组织化学PAP法显示实验性脾虚组和正常对照组大鼠胰岛B细胞(胰岛素细胞)、A细胞(胰高血糖素细胞)和D细胞(生长抑素细胞).结果显示,实验组胰岛素分泌升高(P<0.01),胰高血糖素和生长抑素分泌下降(P<0.05)。实验结果提示大鼠胰岛A、B和D细胞分泌活动的变化与脾虚证的症候可能有密切关系。 相似文献
54.
C. J. Corrigan R. J. Shiner† B. H. Shakur† P. W. Ind† 《Clinical and experimental allergy》2005,35(5):579-584
BACKGROUND: Concomitant methotrexate (MTX) therapy of oral corticosteroid (CS)-dependent asthmatics has been shown to spare CS therapy, but the mechanism is unknown. In a previous report, we showed that MTX increases T cell inhibition by CS. In this report we focus on effects of MTX on immunoglobulin concentrations and their possible clinical relevance. OBJECTIVE: To monitor changes in circulating leucocytes and Ig in a group of these patients during MTX therapy, and to relate these changes to clinical 'response' as defined by oral CS reduction. METHODS: Sixteen severe asthmatics dependent on oral prednisolone 15 (7.5-25) mg/day in addition to high dose inhaled CS were treated with MTX 15 mg intramuscularly, weekly for 28 weeks. Prednisolone dosages were maintained constant for 12 weeks then reduced systematically over the next 16 weeks provided that asthma control did not deteriorate. Patients were classified a priori as 'responders' or 'non-responders' to MTX (reduction of initial oral prednisolone requirement by >or=50% or <50%, respectively). Patients were followed-up for a further 12 weeks after MTX withdrawal. Serum Ig and differential blood leucocyte counts were measured at baseline, 12, 28 and 40 weeks. RESULTS: MTX therapy allowed significant, but individually variable, reductions in oral prednisolone dosages (P<0.00001) without alteration of lung function or symptoms. This was associated with significant reductions in mean serum concentrations of Ig of all classes, which reversed following MTX withdrawal. Reductions in IgE and IgG were significantly greater in the MTX 'responders' as compared with 'non-responders', and changes in IgE, IgG and IgM correlated with changes in prednisolone requirements. Differential blood leucocyte counts showed no significant variation. CONCLUSION: MTX therapy reduced oral CS requirements in these severe asthmatics to a degree which correlated with reduced circulating Ig but not lymphopaenia, suggesting a possible cause and effect relationship. These reductions might also contribute to the documented incidence of opportunistic infection in these circumstances. 相似文献
55.
Janice M. Sigmon 《Journal of clinical apheresis》1992,7(3):163-168
Advances in medical knowledge and technology have identified the essential elements involved in the human immune system, their relationships and interactions, and offer more advanced concepts in the design, function, and maintenance of immune response. Immune response begins with the earliest progenitor cell and transfers its legacy of protection through white blood cells and the complement system. A basic understanding of immunology is essential to the hemapheresis practitioner as new treatment regimens requiring hemapheresis interventions develop. © 1992 Wiley-Liss, Inc. 相似文献
56.
7例晚期瘤性胸水的肿瘤浸润淋巴细胞(TIL)经体外诱导培养3~12d,扩增1~9倍.其CD8及IL-2R阳性细胞百分率增加2.43和2.76倍;NK活力增加3.29倍,与培养前后比较有显著差异。TIL/rIL-2(重组人白细胞介素2)胸腔内回输后,4例胸水及胸水中肿瘤细胞消失,癌胚抗原(CEA)回至正常水平,2例胸水减少,1例因多房性胸水停止治疗,CEA水平上升。经1~8个月随访患者心、肝、肾功能正常。 相似文献
57.
本文观察16例大肠癌病人的癌组织培养上清液对人T细胞的增殖,ZL—2产生的影响和病理Dukes分期的关系,发现癌组织的TDSF对T细胞的增殖有显著抑制作用,对ZL—2的产生抑制作用不明显,对T细胞增殖率在DukesA与B期,其值与对照有显著差异(0.01P<0.05).在C期有非常显著差异(P<0.01).说明大肠癌组织确实分泌有能造成宿主免疫功能下降的抑制物质.且免疫作用不是通过ZL—2环节发生. 相似文献
58.
本文应用单克隆抗体检测33例原发性肺癌病人治疗前后外周血中T淋巴细胞亚群变化。结果提示:肺癌病人外周血中T细胞亚群明显有别于正常人,主要表现为T_H细胞降低和T_S细胞升高以及T_H/T_S比值明显倒置。短期观察结果表明,肺癌病人外周血中T_S细胞持续升高和T_H/T_S比值持续降低者,预后不良。临床检测T细胞亚群变化及它们的动态变化可作为判断宿主抗肿瘤免疫功能状态、病情发展和预后的敏感指标。 相似文献
59.
为探讨免疫性血小板减少性紫癜(ITP)中医辨证分型与免疫机理的关系,将ITP患者中医辨证分型结合血小板相关抗体(PAIg)及T淋巴细胞亚群进行分析。发现作为本病主要抗体的PAIgG脾肾阴亏型明显高于脾虚失统型(P<0.01);OKT8+值亦显著高于脾虚失统型(P<0.05),OKT4+/OKT8+比值则明显低于脾虚失统型(P<0.05)。提示脾肾阴亏型的免疫损伤程度较脾虚失统型严重。 相似文献
60.
抗乙肝胎盘转移因子的特异免疫活性观察 总被引:8,自引:0,他引:8
本研究由HBVM-Ab阳性胎盘提取的抗乙肝胎盘转移因子(PSTF)的特异免疫活性证明,经注射,小鼠外周血淋巴细胞明显增多,胸腺重量和指数亦显著增加,酯酶染色证明75%属T-样淋巴细胞,25%属Thy-样淋巴细胞,人白细胞或小鼠白细胞体外转移PSTF特异免疫活性、或豚鼠和小鼠体内转移PSTF特异免疫活性,再取其白细胞作白细胞粘附抑制、白细胞移动抑制、特异淋巴细胞转化、小鼠足掌注射和诱生γ-干扰素试验 相似文献