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891.
Collagen-induced arthritis (CIA) is an animal model for rheumatoid arthritis. The disease is elicited by immunization of genetically susceptible DBA/1 mice with type II collagen, resulting in a debilitating arthritis characterized by inflammation and involvement of multiple joints. We investigated the role of endogenous interleukin (IL)-12 in the pathogenesis of this disease by undertaking an analysis of IL-12-deficient mice on the DBA/1 genetic background after immunization with type II collagen. Both the incidence and severity of disease were significantly reduced in mice unable to produce biologically active IL-12. Concomitant decreases were observed in serum levels of pathogenic, collagen-specific IgG2a antibodies and collagen-induced secretion of interferon-γ by immune splenocytes in vitro, consistent with an impaired T helper-1 response. There were, however, a few animals which developed severe disease in a single paw in spite of this highly diminished Th1 response. Taken together, these results demonstrate an important role for IL-12 in the pathogenesis of CIA, although it is not absolutely required for disease development.  相似文献   
892.
A number of structurally diverse antigens preferentially stimulate the synthesis of IgE antibodies, but no unifying principle has been proposed that explains the nature of isotype selection. In the present study, we show that common allergens present in bee venom, house dust mite emanations and parasite proteins induce mast cell and basophil degranulation and stimulate interleukin-4 synthesis, and secretion in the absence of antigen-specific IgE. These data point to a linkage between the initial activation of cells of the innate immune system and subsequent adaptive immune responses. They suggest that IgE-independent mast cell and basophil degranulation is predictive of potential allergenicity and can be evaluated by means of a cellular assay. Our study indicates that non-immunological degranulation by prototypic allergens, such as bee venom phos-pholipase A2 or proteases associated with house dust mite emanations, is critically dependent on enzymatic activity. These findings have potentially important implications for vaccine design in allergic and parasitic disease.  相似文献   
893.
γδ T cell populations are known to expand in response to intracellular bacterial infectious agents regardless of previous priming. We have shown previously that soluble factor(s) produced by Mycobacterium-stimulated monocytes activate cord blood γδ T cells to proliferate. In this study, we investigated whether cytokines produced by monocytes are responsible for γδ T cell activation in vitro: interleukin (IL)-1β, IL-6, IL-8, IL-12, tumor necrosis factor (TNF)-α and granulocyte/macrophage colony-stimulating factor were examined. Recombinant human IL-12 stimulated γδ T cells, but not αβ T cells in peripheral blood mononuclear cells, to express CD25 on their surfaces, and to expand in number in vitro. IL-12-primed γδ T cell numbers increased to a greater extent in the culture to which exogenous IL-2 (5 U/ml) was added. Anti-TNF-α monoclonal antibody inhibited IL-12-induced up-regulation of CD25 on γδ T cells, suggesting that endogenous TNF-α may play a role in IL-12-induced activation of γδ T cells. Recombinant TNF-α synergistically augmented IL-12-induced activation of γδ T cells. Furthermore, IL-12 up-regulated TNF receptors on γδ T cells in vitro: TNF-α binding to its receptor induced CD25 expression on the γδ T cells in an autocrine or paracrine fashion, or perhaps both. It also became evident that both IL-12 and TNF-α were produced by mycobacterial lysate-stimulated monocytes. Taken together, these results suggest that upon confrontation with mycobacterial organisms, γδ T cells can be quickly and antigen-nonspecifically activated by soluble factors including IL-12 and TNF-α, both of which are produced by mononuclear phagocytes in response to mycobacterial organisms.  相似文献   
894.
To investigate the role of interleukin (IL)-4 during the triggering of collagen-induced arthritis, we examined the effects of the I-Ab and I-E protective/suppressive genes and passively administered anti-IL-4 monoclonal antibody. In contrast to the action of I-E expression on its own, which has mainly a suppressive effect post-triggering, the combination of I-Ab and I-E had a marked protective effect. Assuming, on the basis of previous experience with the I-Ab allele, that it might act through suppressing early IL-4 production, we treated mice with the 11B11 IL-4-neutralizing antibody around the time of initial immunization with collagen. Treatment over a period extending to 6 days post-immunization exacerbated the arthritis, but when curtailed to 2 days post-immunization (and tested in pristane-primed animals), the disease was reduced. We conclude that IL-4 plays an essential role in triggering the disease.  相似文献   
895.
目的 探讨内皮祖细胞来源的外泌体在体外循环引起的脑损伤中的作用机制.方法 选取雄性SD大鼠45只,随机分为假手术组、体外循环组与外泌体处理组,每组15只.假手术组大鼠采用气管插管机械通气,仅在右股动脉、右颈内静脉穿刺置管;体外循环组建立无血预充非停跳体外循环术后认知功能障碍模型;外泌体处理组大鼠动物模型同体外循环组,待...  相似文献   
896.
目的 探讨白细胞介素-11(interleukin-11,IL-11)在小鼠脑缺血再灌注损伤中的保护作用及机制研究.方法 选择SPF级C57BL/6雄性小鼠60只,随机分成为对照组、模型组和IL-11组,每组各20只,通过线栓法构建脑缺血再灌注损伤.应用TTC染色检测脑组织梗死面积,采用Longa评分法评估各组小鼠的神...  相似文献   
897.
目的:研究解毒化浊促愈汤治疗溃疡性结肠炎的疗效及对白细胞介素-6(Interleukin-6,IL-6)、肿瘤坏死因子(Tumor Necrosis Factor-alpha,TNF-α)水平的影响。方法:选取自2017年8月-2018年10月在河南省中医院肛肠科就诊的溃疡性结肠炎患者60例为研究对象,随机将分为观察组与对照组,每组各30例。对照组用美沙拉嗪治疗,观察组在对照组治疗基础上联合解毒化浊促愈汤治疗。两组均连续治疗6周,比较两组患者治疗后的临床疗效以及治疗前后的IL-6、TNF-α水平变化情况。结果:治疗后观察组临床症状明显改善,总有效率为93.3%(28/30),明显高于对照组的70.0%(21/30)。治疗后,两组患者的血清IL-6、TNF-α水平分别较治疗前显著降低(P<0.05),且观察组各指标水平均低于对照组,差异显著(P<0.05)。结论:此方治疗方法能够明显缓解患者的临床症状,抑制炎症反应,提高临床疗效,具有临床推广价值。  相似文献   
898.
目的:探究归脾丸加减对围绝经期功血患者免疫功能、白细胞介素2(IL-2)、可溶性白细胞介素-2受体(sIL-2R)的影响。方法:选取2019年3月至2018年6月山东省济南市中西医结合医院收治的符合纳入条件的围绝经期功血患者118例作为研究对象,按照就诊顺序编号随机分为对照组和观察组,每组59例。对照组常规西医治疗,观察组加用归脾丸加减治疗,均治疗3个月。观察2组治疗前、完成治疗后T淋巴细胞亚群、IL-2、sIL-2R、凝血功能、子宫内膜厚度、激素水平、症状积分变化;完成治疗后统计治疗过程中的不良反应。结果:1)完成治疗后,2组CD3+、CD4+、CD4+/CD8+、IL-2较治疗前均显著升高,CD8+、sIL-2R则显著下降(P<0.05);完成治疗后观察组CD8+、sIL-2R显著低于于对照组,余均高于对照组(P<0.05)。2)完成治疗后2组凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、凝血酶时间(TT)、子宫内膜厚度较治疗前均显著下降(P<0.05),完成治疗后观察组以上指标均显著低于对照组(P<0.05)。3)完成治疗后2组黄体生成素(LH)、促排卵生成素(FSH)、雌二醇(E2)、孕酮(P)、血管内皮生长因子(VEGF)、碱性成纤维细胞生长因子(bFGF)较治疗前均显著下降(P<0.05),完成治疗后观察组以上指标均显著低于对照组(P<0.05)。4)完成治疗后2组月经周期、阴道出血量、阴道出血天数、神疲乏力积分较治疗前均显著下降(P<0.05),完成治疗后观察组以上指标均显著低于对照组(P<0.05)。5)完成治疗后观察组胃肠道反应、体质量增加、肝功能异常、乳房胀痛发生率均显著低于对照组,2组比较差异有统计学意义(P<0.05)。结论:归脾丸加减能提高围绝经期功血患者免疫功能,抑制IL-2、sIL-2R,改善凝血功能,从而改善症状,提高疗效。  相似文献   
899.
目的观察"肾脑相济"电针对阿尔茨海默病(AD)模型小鼠行为学和大脑皮质炎性因子白细胞介素-1β(IL-1b)和肿瘤坏死因子-α(TNF-α)表达的影响,探究"肾脑相济"电针疗法治疗阿尔茨海默病的作用机理。方法将7月龄雄性SAMP8小鼠随机分成模型组、西药组和电针组,每组6只;将SAMR1小鼠作为对照组。西药组给予盐酸多?哌齐灌胃,电针组电针百会、肾俞和三阴交。采用Morris水迷宫观察小鼠行为学,应用免疫组化法、Western Blot法测定大脑皮质区IL-1b、TNF-α的阳性细胞数和蛋白表达。结果与对照组比较,模型组小鼠学习记忆能力明显下降,IL-1b、TNF-α的表达升高,差异有统计学意义(P<0.05);与模型组比较,西药组和电针组小鼠学习记忆能力增强,IL-1b、TNF-α的表达降低,差异有统计学意义(P<0.05);与西药组比较,电针组小鼠学习记忆能力及IL-1b、TNF-α的表达变化不明显,差异无统计学意义(P>0.05)。结论"肾脑相济"电针疗法可以改善SAMP8模型小鼠的学习和记忆能力,降低大脑皮质区IL-1b、TNF-α的含量,从而对阿尔茨海默病达到治疗效果。  相似文献   
900.
Low-grade inflammation is a factor that predisposes to many obesity-related comorbidities. The immune mechanisms controlling the inflammatory response related to the secretory activity of adipocytes and its consequences for the organism are still under investigation. Methods: 84 obese adult volunteers (BMI ≥ 30 kg/m2) were tested by BIA. Serum samples were collected to analyze the concentrations of interleukins IL-17A, IL-17E and IL-17F. The subjects completed the original questionnaire, the FFQ-6 food consumption frequency questionnaire and the food diary. Results: The level of IL-17E and IL-17F was positively correlated with the BMI value and the level of IL-17E increased with the content of subcutaneous fat. Its increased blood concentration was also observed in individuals who declared that they were diagnosed with atherosclerosis and/or were taking beta-blockers. Products that were related with a low level of the above-mentioned interleukins were vegetables, groats, eggs, red meat, fast-food and alcohol. The level of these interleukins was positively correlated with the frequent consumption of confectionery and breakfast cereals. Nutrients that decreased the concentrations of IL-17 isoforms were potassium, iron, vitamins B6 and C, and folic acid. Conclusions: Both IL-17E and IL-17F may be closely related to the intensity of low-grade inflammation and be biomarkers of cardiovascular disease risk. Food products or the nutrients they contain may affect the levels of the above-mentioned interleukins as well as IL-17A.  相似文献   
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