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51.
Two new T cell subsets may be involved in allergic rhinitis (AR) pathogenesis: Th17 and T regulatory cells, mainly producing IL-17 and TGF-β respectively. Successful Sublingual Immunotherapy (SLIT) induces relevant immunological changes, thus the aim of this study was to evaluate serum IL-17 and TGF-β levels in AR patients treated with SLIT for 2 years. Patients' blood samples were collected before initiating SLIT (baseline), three months after the end of the first pre-seasonal SLIT course, and at the end of the second pre-seasonal course. IL-17 was detectable only in the most severe allergic patients. SLIT significantly induced an increase in serum TGF-β levels. There was moreover a significant relationship between TGF-β and symptom severity and drug use at the end of the study. Therefore, this study provides clinically relevant evidence that two pre-seasonal SLIT courses may significantly affect serum TGF-β levels.  相似文献   
52.
丹参与雷公藤多甙联合治疗急性坏死性胰腺炎的实验研究   总被引:4,自引:0,他引:4  
目的 探讨丹参与雷公藤多甙联合应用对急性坏死性胰腺炎 (acutenecrotizingpancreatitis,ANP)的治疗作用。 方法 采用单次过量 2 0 %L 精氨酸 (10 0 0mg/ 10 0g大鼠体重 )皮下注射建立ANP动物模型。测定血清淀粉酶、TNF α、IL 1β水平 ,并观察胰腺组织的病理变化。根据血清淀粉酶、TNF α、IL 1β水平及胰腺组织的变化来评价胰腺炎的严重程度。 结果 大鼠皮下注射过量L 精氨酸后 ,血清淀粉酶、TNF α、IL 1β水平升高 ,胰腺变性坏死。丹参与雷公藤多甙联合治疗ANP ,可显著降低血清淀粉酶、抑制炎症细胞因子的过度生成 ,组织受损程度明显减轻。结论 丹参与雷公藤多甙联合应用对ANP动物模型具有很好治疗效果 ,可能具有临床应用价值  相似文献   
53.
目的 探讨 IL - 4和 IL - 10在诱导异种骨移植免疫耐受中的作用。方法 反应细胞为 BAL B/c小鼠脾淋巴细胞 ,刺激细胞为新西兰白兔血淋巴细胞 ,刺激抗原为兔骨上清液。采用经典的混合淋巴细胞培养法及骨上清液与淋巴细胞混合培养法作为异种骨移植的体外实验模型。在各培养液中分别加入 IL - 4、IL - 10及两者联合应用 ,通过测定其 3H- Td R掺入率 ,观察不同细胞因子对刺激淋巴细胞增殖的影响。结果 无论在细胞刺激组还是骨上清液刺激组 ,IL- 4对淋巴细胞增殖均有显著抑制作用 (P<0 .0 0 1和 P<0 .0 5 ) ,IL- 10未表现出抑制作用 (P>0 .0 5 )。在两组 IL- 4和 IL - 10联合应用均产生比 IL - 4单独应用更为明显的细胞增殖抑制作用 (P<0 .0 0 1和 P<0 .0 5 )。结论  IL - 4对由细胞或骨上清液刺激产生的淋巴细胞增殖均有很好的抑制作用 ,IL- 10没有表现出抑制作用 ;IL- 4与 IL- 10联合应用有协同抑制作用。  相似文献   
54.
目的 探讨通过门静脉系统局部应用白细胞介素 12 (IL 12 )对于肝转移肿瘤的治疗作用。方法 通过门静脉注射 2× 10 5个MCA 2 0 5肿瘤细胞建立小鼠肝转移肿瘤模型 ,同时脾脏被移植到皮下 ,作为反复多次向门静脉系统注射的途径。第 3~ 7天 ,0 1μgIL 12通过腹腔或脾脏注射 ,同时对照组中通过脾脏注射等体积的平衡盐水。第 2 1天检查肝转移肿瘤的情况。结果 在肝转移模型中 ,IL 12腹腔注射组和IL 12脾脏注射组的肝脏重量 (1 33± 0 0 8)g和 (1 2 9± 0 0 7)g明显小于对照组 (1 92± 0 17)g ,P <0 0 5 ,IL 12腹腔注射组和IL 12脾脏注射组的肝脏转移结节数目 (1 5 3± 0 5 8,0 6 0± 0 89)明显少于对照组 (18 2 5± 5 71,P <0 0 5 )。在IL 12脾脏注射组中 (n =6 ) ,3只小鼠的肝脏肿瘤完全消失。结论 通过门静脉系统局部应用IL 12是治疗肝转移肿瘤的有效方法。  相似文献   
55.
Th2细胞因子调节哮喘炎症细胞转运机制的研究   总被引:1,自引:0,他引:1  
目的 探讨Th2细胞因子IL-5、IL-13调节哮喘炎症过程中肺和骨髓之间的细胞转运机制。方法 建立哮喘动物模型,获取肺泡灌洗液,检测IL-5、IFN-γ,浓度并进行病理分析;应用原位杂交技术检测肺组织IL-5、IL-13 mRNA表达和骨髓IL-5mRNA表达;免疫组化法观察肺、骨髓IL-5免疫反应细胞;流式细胞仪检测骨髓CD34、CD3阳性细胞。结果 哮喘组肺泡灌洗液IL-5浓度明显高于对照组(P<0.001);哮喘组肺组织病理改变显示小气道痉挛,管壁周围炎性细胞浸润,以嗜酸粒细胞、淋巴细胞为主;哮喘组肺组织IL-5、IL-13 mRNA表达较对照组显著增加(P<0.01);哮喘组骨髓IL-5 mRNA阳性细胞明显增加(P<0.001),与肺组织IL-5 mRNA表达的增高密切相关(P<0.05);此外,哮喘组肺组织和骨髓IL-5免疫反应细胞显著增加(P<0.01),骨髓CD34、CD3细胞均显著增高(P<0.01),并且CD34增高与骨髓细胞表达IL-5 mRNA密切相关(P<0.05)。结论IL-5可能在转录和转录后水平均参与调节骨髓嗜酸粒细胞的功能和炎症细胞在肺和骨髓之间的转运。  相似文献   
56.
Although it has been known that y8 T cells may play an important role in the immune response to infection of Mycobacterium tuberculosis (M. tb), the mechanisms by which the T8 T cells participate in the innate and/or acquired immunity to tuberculosis (TB) have not been full elucidated. In the present study, 27 patients with active pulmonary TB and 16 healthy donors (HD) were performed. We found that proportion of IL-17-producing cells among lymphocyte was similar between TB patients and HD, whereas the proportions of γδ T cells in IL-17- producing cells (59.2%) and IL-17-producing cells in γδ T cells (19.4%) in peripheral blood were markedly increased in TB patients when compared to those in HD (43.9% and 7.7%, respectively). In addition, the proportions of IFN-γ-producing γδ T cells in TB patients were obviously lower than that in HD. Upon re-stimulated with M. tb heat-treated antigen (M. tb-HAg) in vitro, fewer IL-17-producing γδ T cells were generated from HD and TB patients, whereas IFN-γ-producing γδ T cells were increased in TB patients compared to that in HD. Our findings in TB patients and healthy human were consistent with other murine investigation that the IL-17- producing γδ T cells were main source of IL-17 in mouse model of BCG infection, suggesting that γδ T cells might be involved in the formation of tubercular granuloma in pulmonary TB patients, but need further identification. Cellular & Molecular Immunology. 2008;5(3):203-208.  相似文献   
57.
采用~(125)I 标记小鼠抗人IL—2受体(P55)的抗Tac(CD_(25))单克隆抗体,成功地建立了人IL—2受体的免疫放射分析法,动态观察了人外周血淋巴细胞经PHA 刺激24、48和72h 后IL—2受体表达的时间曲线,通过Scatchard 作图分析表明~(125)I—抗Tac 单克隆抗体与PHA 活化的上述三个时间点的T 淋巴细胞的最大结合容量(B_(max))分别为43000位点/细胞、54000位点/细胞和61000位点/细胞。本研究为临床IL—2受体检测提供一种简便的免疫放射测定法。  相似文献   
58.
High cord blood immunoglobulin E (cbIgE) is known to be associated with increased risks of atopic diseases in childhood. The relationship between genetic polymorphisms and high cbIgE has not been well documented. A cross-sectional study was conducted to assess the association between cbIgE and genetic polymorphisms of interleukin (IL)-4 -590C/T, the beta-subunit of the high-affinity receptor for IgE (FcepsilonRI-beta) E237G, lymphotoxin (LT)-alphaNcoI alleles, and tumor necrosis factor (TNF)-alpha -308G/A. A total of 320 mother-neonate pairs were recruited from four maternity hospitals from different locations of Taiwan. Cord blood was obtained and assayed for cbIgE. Polymerase chain reaction followed by restriction fragment length polymorphism was used to assess the genotypes. Three hundred pairs of mothers and neonates were included in the final analysis. Infants with IL-4 -590 C allele were found to have higher risk of elevated cbIgE (> or =0.35 IU/ml, 24.3%) (p = 0.004). After adjusting for gender, birth order, maternal age, and history of allergic disease in maternal and paternal families, odds ratios for CC and CT genotypes were 4.41 and 3.16 (95% confidence interval 0.78-22.67, and 1.66-6.13), respectively, using TT genotype as reference. The genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha were not associated with cbIgE before or after the adjustment. Our finding suggested a significant association of cbIgE with genetic polymorphism of IL-4 -590C/T, but not with the genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha.  相似文献   
59.
BACKGROUND AND METHODS: The endogenous inhibitor of nitric oxide synthase (NOs) asymmetrical dimethyl-arginine (ADMA) has been implicated as a possible modulator of inducible NOs during acute inflammation. We examined the evolution in the plasma concentration of ADMA measured at the clinical outset of acute inflammation and after its resolution in a series of 17 patients with acute bacterial infections. RESULTS: During the acute phase of inflammation/infection, patients displayed very high levels of C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin and nitrotyrosine. Simultaneous plasma ADMA concentration was similar to that in healthy subjects while symmetric dimethyl-arginine (SDMA) levels were substantially increased and directly related with creatinine. When infection resolved, ADMA rose from 0.62 +/- 0.23 to 0.80 +/- 0.18 micromol/l (+29%, P = 0.01) while SDMA remained unmodified. ADMA changes were independent on concomitant risk factor changes and inversely related with baseline systolic and diastolic pressure. Changes in the ADMA/SDMA ratio were compatible with the hypothesis that inflammatory cytokines activate ADMA degradation. CONCLUSIONS: Resolution of acute inflammation is characterized by an increase in the plasma concentration of ADMA. The results imply that ADMA suppression may actually serve to stimulate NO synthesis or that in this situation plasma ADMA levels may not reflect the inhibitory potential of this methylarginine at the cellular level.  相似文献   
60.
Previously, we reported that allogeneic skin grafts were rapidly rejected by CD28 and CD40 ligand double deficient mice mediated by CD8+ T cells. These results indicated that some elements in addition to CD28- and CD40-mediated costimulation provide stimulatory signals for the activation of donor-specific CD8+ T cells. In this report, we investigated the role of inflammation associated with transplantation on costimulation-independent priming of CD8+ T cell during graft rejection. B6 RAG1 KO mice were transplanted with BALB/c-skin and adoptively transferred with syngeneic CD8+ T cells the same day or 50 days after transplantation. When blockade of CD28- and CD40-mediated costimulation failed to prevent acute rejection of freshly transplanted skin grafts, it efficiently delayed rejection of well-healed skin grafts. These results showed that factors associated with transplantation have essential roles in inducing costimulation blockade-resistant allograft rejection. Costimulation blockade failed to prevent acute graft-infiltration of NK cells and increasing expression of intragraft IL-12 and IL-15. These factors may trigger the graft-infiltration and priming of CD8+ T cells to induce costimulation blockade-resistant allograft rejection.  相似文献   
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