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21.
甲基强的松龙治疗实验性变态反应性脑脊髓炎的作用机制   总被引:1,自引:0,他引:1  
目的:研究细胞因子、T细胞凋亡和淋巴细胞增殖在实验性变态反应性脑脊髓炎(EAE)形成中的作用及甲基强的松龙(MP)治疗EAE的作用机制。方法:采用人脑纯化的髓鞘碱性蛋白(MBP)与完全福氏佐剂免疫Lewis大鼠,建立EAE动物模型。用双抗体夹心ELISA法检测各组大鼠血清中IL-10、TNF-α、IFN-γ的含量:流式细胞仪检测外周血T细胞凋亡;3H-TdR释放法检测外周血淋巴细胞转化率。结果:与对照组比较,EAE组的外周血IFN-γ、TNF-α水平明显增高,IL-10水平明显降低,MP治疗后IFN-γ和TNF-α水平下降,IL-10浓度上调。MP还诱导外周血T细胞凋亡和抑制MBP致敏淋巴细胞增殖并呈剂量依赖性。结论:应用人MBP成功建立EAE大鼠模型,MP可能通过调节Th细胞因子格局、促进Th2细胞因子分泌、抑制MBP致敏淋巴细胞增殖及外周血T细胞凋亡而发挥治疗多发性硬化的作用。  相似文献   
22.
In the last years, granulocyte and granulocyte-macrophage colony-stimulating factors (G-CSF and GM-CSF) are being increasingly used and several cutaneous eruptions have been reported in relation to these treatments. In 1991 Horn et al. described three patients with maculopapular eruption that paralleled the time of infusion of GM-CSF. Two of the cases showed an increase in the number and size of macrophages in the biopsy specimen. Since then, several cases have been reported showing this histopathological alteration that has been considered characteristic of reaction to G-CSF or GM-CSF. Although maculopapular eruption with enlarged macrophages can appear after chemotherapy treatment, we have found that the presentation of this eruption after the beginning of cytokine treatment is suggestive of the involvement of G-CSF and GM-CSF in the eruption. We described eight cases of patients treated with G-CSF or GM-CSF that developed maculopapular eruptions with enlarged macrophages.  相似文献   
23.
BACKGROUND: One to two percent of infants suffer from IgE-mediated allergic reactions against cow's milk proteins. Most children develop clinical tolerance, but approximately 15% are still allergic by the age of 10 years. Little is known about the T cell epitopes in individual cow's milk protein in relation to allergy and tolerance. OBJECTIVE: To identify T cell epitopes in alphas1-casein, the most abundant milk protein, and to investigate T cell responses toward these epitopes in allergic, atopic and non-atopic children. METHODS: Allergen-specific T cell lines (TCLs) were derived from peripheral blood mononuclear cells of 11 cow's milk allergic, nine atopic and nine non-atopic children. T cell responses were measured to alphas1-casein and to overlapping peptides (18-mers), spanning the alphas1-casein molecule. Proliferation was determined by incorporation of (3)H-thymidine, and cytokine production (IL-10, IL-13 and IFN-gamma) was measured by ELISA. RESULTS: Four main regions (amino acid (AA) residues 43-66, 73-96, 91-114 and 127-180) in the alphas1-casein molecule were immunogenic to T cells, among which the AA residues 133-156 spanned the immunodominant part. Only subtle differences were found in peptide recognition between the subject groups. Some of the peptides induced slightly Th1- or Th2-skewed cytokine responses. The increased levels of IL-10 in response to alphas1-casein observed in TCLs from atopic children appeared not to be linked to recognition of specific IL-10-inducing epitopes. CONCLUSIONS: The immunodominant sequence in alphas1-casein is spanned by AA residues 133-156. Tolerance towards alphas1-casein in atopic children may be mediated by an overall induction of IL-10 and not by recognition of certain T cell epitopes. The identified T cell epitopes in children with cow's milk allergy may be useful targets in developing peptide immunotherapy.  相似文献   
24.
BACKGROUND: Adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) are thought to contribute to the airway inflammation and airway hyper-responsiveness (AHR) of allergic asthma. Some differences from allergic asthma have been noted, including airway neutrophilia, and the involvement of ICAM-1 in toluene diisocyanate (TDI) asthma is currently unclear. OBJECTIVE: We utilized mice lacking ICAM-1 expression (ICAM-1(-/-)) to investigate the role of ICAM-1 in airway inflammation and AHR in TDI-induced asthma. METHODS: Male C57BL/6J mice (ICAM-1(+/+)) and ICAM-1(-/-) mice were intranasally sensitized to TDI solution or solvent alone. Airway inflammation, AHR and cytokine secretion were assessed 24 h after challenge by TDI or solvent. The production of antigen-specific IgG and IgE by TDI sensitized and non-sensitized mice was determined. RESULTS: TDI challenge to ICAM-1(+/+) mice induced an increase in airway inflammatory cell numbers, AHR and cytokine secretion of TNF-alpha, macrophage inflammatory protein-2 (MIP-2), IL-4, IL-5 and IFN-gamma into the bronchoalveolar lavage fluid. All these pathophysiological changes were reduced in ICAM-1(-/-) mice. Serum levels of TDI-specific IgG and IgE of ICAM-1(-/-) and ICAM-1(+/+) mice were comparable. CONCLUSION: These results suggest that ICAM-1 plays an essential role in airway inflammation and AHR in TDI-induced asthma.  相似文献   
25.
目的:探讨大负荷体能训练对大学生篮球运动员细胞免疫功能的影响。方法:14名男子大学生篮球运动员进行为期16周的集训,在训练期间分次对运动员外周血淋巴细胞亚群(CD3+、CD4+/CD8+淋巴细胞比值、NK细胞比例)和Th1/Th2细胞因子 mRNA表达进行检测。结果:在两次分别持续了6周的训练期后,运动员外周血CD3+淋巴细胞数于增加后出现显著下降,从第7周的峰值(59.74±7.18)下降至第16周的最低值(52.02±7.92)(P<0.001);CD8+细胞数第16周(31.15±6.25)与第3周(37.98±7.05)相比显著下降(P<0.05);NK细胞数从第7周的最高值(19.62±5.21)下降至第14周的最低值(14.41±7.93)(P<0.05);IL-4 mRNA表达训练后与基础值(6.56±0.71)相比显著增加,从第7周的7.04±0.35和第14周的7.30±0.25,直至第16周达到最大值7.36±0.45(P<0.05),其他指标的变化不具有统计学意义。结果提示,大负荷训练使运动员细胞免疫功能削弱,Th1/Th2平衡向Th2方向漂移。  相似文献   
26.
27.
Our objective was to investigate the initial levels of circulating proinflammatory cytokines, such as interleukin 1β (IL-1β), interleukin 6 (IL-6), and tumour necrosis factor alpha (TNF-α), of certain acute-phase proteins, such as C-reactive protein (CRP), fibrinogen (FBN) and albumin, and of the glycoprotein fibronectin at presentation and their daily variation during the clinical course of community-acquired pneumonia (CAP) in relation to clinical and laboratory indices of infection. Thirty otherwise healthy hospitalized patients aged 48 ± 3 years (mean ± SEM) and with bacteriologically confirmed CAP were studied prospectively. IL-1β and IL-6 were found to be 15-fold higher on admission (122 ± 9 pg mL?1 and 60 ± 4 pg mL?1 respectively), whereas TNF-α was three-fold higher (102 ± 5 pg mL?1) than those of controls, all of them showing a decline towards normal. Initial CRP levels were increased 90-fold (416 ± 1 mg L?1), whereas fibronectin levels were reduced (242 ± 9 mg dL?1). The presence of parapneumonic effusion was associated with a higher TNF-α serum level (127 ± 7 vs. 86 ± 4 pg mL?1, P = 0.0002), a more rapid daily decline in TNF-α (–7.2 ± 0.7 vs. ?3.8 ± 0.5 pg mL?1 day?1, P = 0.0005), a slower rate of decline in CRP (?42.8 ± 3.0 vs. ?54.6 ± 3.0 mg L?1 day?1, P = 0.02) and a slower rate of increase in FBN (5.9 ± 1.0 vs. 11.7 ± 1.0 mg dL?1 day?1), P = 0.001]. Furthermore, daily progression of serum levels of cytokines and acute-phase proteins correlated strongly with pyrexia, erythrocyte sedimentation rate (ESR), neutrophil count, alveolar–arterial oxygen difference and radiographic resolution, clinically manifested by improvement in the patients' condition.  相似文献   
28.
目的观察各类新型吸附剂对重型肝炎患者血浆中的胆红素和细胞因子的吸附性能。方法第一步,收集第一组重型肝炎患者的血浆各3ml,以8种不同的吸附剂(1#~3#为致孔剂浓度分别为3%、1%、5%的壳聚糖,4#为胺基化壳聚糖,5#为苯乙烯/二乙烯苯聚合物,6#为后交连苯乙烯/二乙烯苯聚合物,7#为壳聚糖-苯乙烯/二乙烯苯聚合物,8#为壳聚糖-后交连苯乙烯/二乙烯苯聚合物)各1ml进行吸附,检测对胆红素的吸附能力,做吸附剂筛选实验和吸附实验。第二步,用以上筛选出吸附率较好的两种吸附剂各1ml对第二组患者血浆(各3ml)进行胆红素和细胞因子的吸附实验。结果第一步实验显示胺基壳聚糖(4#)和苯乙烯/二乙烯苯聚合物(5#)有较好的吸附效果,4#吸附剂对总胆红素(TBiL)、直接胆红素(DBiL)、间接胆红素(IBiL)的吸附率分别为50.5%±3.4%、57.0%±11.3%、39.0%±7.2%;5#分别为30.1%±2.5%、32.6%±3.0%、27.6%±2.9%。第二步实验显示4#胺基化壳聚糖吸附后血浆中TBiL、DBiL、IBiL、白细胞介素6(IL-6)和肿瘤坏死因子α(TNF-α)水平下降比5#明显,有统计学意义(P<0.001)。结论胺基化壳聚糖(4#)体外吸附重型肝炎患者血浆中胆红素、细胞因子效果有明显优势。  相似文献   
29.
To determine the levels of maturation and differentiation ofmurine CD4 single-positive (SP) T cells, we compared the secondaryresponses of staphylococcal enterotoxin A (SEA)-induced neonatalthymic, adult thymic and adult splenic CD4 SP T cell blastsprepared from whole or heat-stable antigenlow CD4 SP T cells.Proliferative responses upon re-stimulation with SEA were strongin adult splenic CD4 SP T cell blasts, but quite weak in neonatalthymic and adult thymic CD4 SP T cell blasts. SEA-induced IL-2production was weaker in neonatal thymic blasts than in theadult splenic CD4 SP T cell blasts. In contrast, SEA-inducedIL-4 production was high in neonatal thymic CD4 SP T cell blasts,and low in adult splenic and thymic CD4 SP T cell blasts. Expressionof GATA-3, that directs production of IL-4 in T cells, examinedat protein and mRNA levels, was higher in neonatal thymic cellsthan in adult thymic and splenic cells. These results suggestthat neonatal and adult thymic CD4 SP T cells in the final stageof maturation are relatively immature compared with adult splenicCD4 SP T cells. The cytokine production profile of neonatalthymic CD4 SP T cells suggests that they are inclined towardsa Th2 response.  相似文献   
30.
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