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Cellular adhesion receptor LFA-1 and its ICAM ligands are known to play a role in HIV infection. The presence of these molecules on virions and target cells promotes virus infectivity and has previously been shown to hinder virus neutralization by anti-HIV antibodies. To delineate the effect of these molecules on neutralization of HIV-1, human monoclonal antibodies (MAbs) to V3 and the CD4-binding domain (CD4bd) of gp120 were examined in the presence of anti-LFA-1 MAbs. When either of two anti-LFA-1 MAbs was present, higher levels of virus neutralization were achieved by both anti-V3 and anti-CD4bd MAbs. This effect was observed with primary HIV-1 isolates as well as with a laboratory-adapted strain. However, this activity was seen only when an anti-LFA-1 MAb was combined with anti-gp120 MAbs that exhibited virus-specific neutralizing activities, demonstrating the specificity of both the anti-LFA-1 and anti-gp120 MAbs. Enhanced neutralization by anti-gp120 MAbs was observed if the anti-LFA-1 MAb was present during the initial 24 hr only, if added 24 hr after infection, or if present throughout the culture period. These data suggest that the anti-LFA-1 MAbs could act at different stages of HIV-1 infection, including the initial virus-cell interaction as well as during the amplification and spread of virus from cell to cell. These findings demonstrate the significant role of LFA-1 in HIV-1 infection and have important implications for evaluating the neutralizing activity of anti-HIV antibodies.  相似文献   

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日本血吸虫不同免疫原对小鼠Th1/Th2免疫偏移的影响   总被引:7,自引:1,他引:6  
目的 观察单、双性日本血吸虫感染小鼠后Th1/Th2细胞因子水平的动态变化 ,探讨日本血吸虫不同免疫原对Th1/Th2免疫偏移的影响及与虫卵肉芽肿形成的相关性。方法 用ELISA夹心法检测单、双性日本血吸虫感染小鼠及单性感染 8w双性再感染 0~ 12w ,小鼠脾淋巴细胞培养上清Th1细胞因子IL - 2、IFN -γ和Th2细胞因子IL - 4表达水平。结果 单性感染小鼠 6~ 12w在脾淋巴细胞培养上清中可测出一定量的IL - 2和IFN -γ ,但无明显动态变化 ,而IL - 4未能测出 ;双性感染小鼠IL - 2和IFN -γ在感染后 4~ 6w开始上升 ,8w达高峰 ,随后下降 ,IL - 4则在感染后 8w时迅速上升且随着感染时间延长而明显升高 ,单性感染 8w双性再感染 4w时 ,小鼠脾淋巴细胞培养上清IL - 2、IFN -γ和IL - 4表达水平即迅速升高且在双性再感染 8~ 12w逐渐增强。结论 日本血吸虫不同免疫原对Th1/Th2免疫偏移的影响作用不同 ,Th1优势应答可能主要由虫体抗原诱导 ,Th2优势应答可能主要由虫卵抗原 (SEA)所诱导 ,后者是诱导宿主产生免疫病理反应的主要因素  相似文献   

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Intercellular adhesion molecule-1 (ICAM-1) is expressed abnormally on the bile duct epithelium during the course of primary biliary cirrhosis (PBC), but the importance of ICAM-1 and its lymphocyte function-associated antigen-1 (LFA-1) receptor during the course of nonsuppurative destructive cholangitis (NSDC) has not been defined. To address this question, we defined the relationship between ICAM-1 on the intrahepatic bile duct epithelium and the evolution of NSDC lesions in a mouse graft-versus-host disease (GVHD) model. We also determined the effects of anti-ICAM-1 and anti-LFA-1 treatments on NSDC, intrahepatic lymphokine production, and the homing of lymphocytes to the livers of GVHD mice. ICAM-1 was initially detected on the bile duct epithelium and portal vein endothelium on day 7 of GVHD. There was a significant positive correlation between the intensity of ICAM-1 staining and histological bile duct damage (r =.58, P <.05) between day 3 and 28. Treatment with anti-ICAM-1 (but not anti-LFA-1) decreased both the mean grades of portal inflammation (P =.003) and NSDC (P =.002) lesions compared with control immunoglobulin G (IgG) treatments. Combined treatment with anti-ICAM-1 and anti-LFA-1 caused a further decrease in the amount of portal inflammation and bile duct damage compared with anti-ICAM-1, alone (P =.02). Anti-ICAM-1 treatment also decreased both the percentage of T cells and the production of interleukin-2 (IL-2) and IL-12 in the liver (P <.01), but had no effect on IL-4, IL-10, and interferon gamma. Neither anti-ICAM-1 nor anti-LFA-1 prevented lymphocytes from homing to the liver. These results indicate that both ICAM-1 and LFA-1 are important to the pathogenesis of NSDC.  相似文献   

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We studied the adhesion of human peripheral blood T lymphocytes to human synovial fibroblasts stimulated with interferon-gamma (IFN gamma), tumor necrosis factor alpha (TNF alpha), interleukin-1 beta (IL-1 beta), or combinations of these cytokines. T lymphocytes bound poorly to untreated human synovial fibroblasts. IFN gamma treatment resulted in the largest increase in adhesion, followed by TNF alpha and IL-1 beta. Combinations of IFN gamma + TNF alpha and IFN gamma + IL-1 beta had a synergistic effect on intercellular adhesion molecule 1 (ICAM-1) expression and adhesion. The increase in cellular adhesion induced by cytokines correlated with the up-regulation of the number of cells expressing ICAM-1 and the density of antigen/cell. There was no synergistic effect on leukocyte function-associated antigen 3 (LFA-3) or on HLA class I or class II antigen expression. Adhesion was only partially inhibited by anti-ICAM-1, anti-LFA-1, or anti-CD18. These findings suggest the existence of ICAM-1--independent and CD11/CD18-independent adhesion mechanisms. Anti-LFA-3 was completely ineffective as an inhibitor of adhesion. There was no additive or synergistic advantage of using combinations of antibodies to increase the level of inhibition, i.e., anti--ICAM-1 + anti-LFA-3, anti-ICAM-1 + anti-CD18, or anti-ICAM-1 + anti-LFA-1 (CD11a). Our data indicate that proinflammatory cytokines may play a prominent role in the formation and exacerbation of synovial hyperplasia, by regulating the recruitment and retention of T lymphocytes via the up-regulation of adhesion molecules on synovial fibroblasts.  相似文献   

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目的 探讨Th1和Th2类细胞因子对小鼠感染血吸虫的免疫保护作用. 方法 C57BL/6小鼠48只,抽签法随机均分为4组,白细胞介素(interleukin,IL)-4组,给予IL-4 (200 ng); IL-12组,给予IL-12 (200 ng);胸腺基质淋巴生成素(thymic stromal lymphopoietin,TSLP)组,给予TSLP(200 ng);生理盐水组,给予生理盐水(200μl).4组均为腹腔注射,每周3次,持续注射8周.给药后2周,各组小鼠经皮攻击感染日本血吸虫尾蚴(40±2)条/鼠,感染后第3、6周剖杀,计算各组小鼠虫荷数、肝脏卵荷数.芯片检测各组小鼠感染前和感染后不同时间点血清中IL-5、IL-10、γ-干扰素(interferon-γ,IFN-γ)及肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)的动态变化.观察小鼠肝、脾的病理变化. 结果 细胞因子注射的第8周,IL-4组的Th2类细因子IL-5、IL-10依次为161.97、65.47 μg/ml; TSLP组的IL-5、IL-10依次为132.72、77.18 μg/ml; IL-12组的IL-5、IL-10依次为87.15、12.29 μg/ml;生理盐水组的IL-5、IL-10依次为188.92、167.52 μg/ml.IL-4和TSLP组Th2类细胞因子水平均高于IL-12组,但低于生理盐水组.IL-12组IFN-γ、TNF-α依次为165.7、23.64 μg/ml,水平高于其它各组.感染后3周IL-4、IL-12、TSLP、生理盐水组虫荷数依次为(9.50±4.51)、(12.83±2.32)、(6.75±2.87)、(9.80±3.03)条;感染后6周上述各组虫荷数依次为(18.83±5.91)、(24.80±9.42)、(21.67±3.67)、(17.67±6.74)条,每克肝组织虫卵数依次为(58 286.98±25 351.60)、(80 460.18±35 542.66)、(54 579.56±16 399.21)、(41 094.92±25 598.27).与生理盐水组相比,各实验组虫荷数与每克肝组织虫卵数差异均无统计学意义.感染后第3周,IL-4、IL-12、TSLP、生理盐水组脾指数依次为(0.010±0.002)、(0.011±0.002)、(0.009±0.001)、(0.007 ±0.001),各实验组与生理盐水组相比,差异均有统计学意义(t=3.158、5.076、6.204,P<0.05).感染后第6?  相似文献   

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目的 设计siRNA表达质粒干扰CAP10基因的合成,将siRNA干扰前与干扰后的新型隐球菌菌液经呼吸道感染小鼠分别建立动物模型,行组织病理学检查与细胞因子检测,探讨CAP10基因对Th1/Th2 免疫应答的影响。方法 建立小鼠吸入感染隐球菌模型,在感染后第7 d(急性期),PAS染色观察小鼠肺组织病理变化,并采用酶联免疫吸附试验定量检测小鼠血液中的Th1(IFN-γ、TNF-α)、Th2细胞因子(IL-10)水平。结果 急性期小鼠血液内IFN-γ、TNF-α及IL-10浓度测定分别为:对照组(uninfected组)(19.24±1.31)pg/mL,(36.94±2.04)pg/mL及(18.32±3.00)pg/mL,新型隐球菌未干扰组(WT组)(14.34±1.26)pg/mL,(25.37±1.37)pg/mL及(72.96±8.83)pg/mL,新型隐球菌干扰组(siRNA-CAP10组)(14.63±0.95)pg/mL,(26.22±1.55)pg/mL及(38.73±4.61)pg/mL。与对照组相比,WT组和siRNA-CAP10组Th1因子IFN-γ及TNF-α水平明显降低(P<0.01),Th2细胞因子IL-10水平明显增高。WT组与siRNA-CAP10组相比,IFN-γ及TNF-α水平未见明显增高而IL-10水平明显增高(P<0.01)。IFN-γ/IL-10及TNF-α/IL-10的比率分别为:对照组1.08±0.21,2.07±0.34,WT组0.20±0.03,0.35±0.05,siRNA-CAP10组0.38±0.04,0.69±0.09。WT组和siRNA-CAP10组IFN-γ/IL-10及TNF-α/IL-10的比率较对照组明显减少(P<0.01);WT组IFN-γ/IL-10及TNF-α/IL-10的比率亦明显低于siRNA-CAP10组(P<0.01)。结论 在新型隐球菌感染小鼠中,CAP10基因的表达与抗真菌的免疫反应有关,其下调有利于控制新型隐球菌播散,有利于Th1/Th2比率趋于平衡,在调节炎症反应方面有重要作用,有望成为新的分子治疗靶点。  相似文献   

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目的 观察日本血吸虫感染小鼠肝肉芽肿病变与一氧化氮 (NO)、Th1/Th2细胞因子水平的动态变化 ,探讨NO介导Th1/Th2免疫偏移在血吸虫卵肉芽肿病变中的作用。方法 采用石蜡切片 ,HE染色后观察感染小鼠肉芽肿病变。用硝酸还原酶法和ELISA夹心法分别检测日本血吸虫感染小鼠 0~ 12周血清及脾CD+ 4 T淋巴细胞培养上清NO、IFNγ和IL - 4表达水平 ,并进行相关分析。结果 感染小鼠 0~ 12周血清和脾CD+ 4 T淋巴细胞培养上清NO表达水平与小鼠肝肉芽肿病变动态相一致 ,并呈显著正相关 ,与IFNγ表达水平呈显著正相关 ,而与IL - 4在小鼠感染慢性期 (12周 )呈显著负相关。结论 NO在日本血吸虫感染小鼠肝肉芽肿病变过程中可能是一种与Th1/Th2细胞因子具有同样重要作用的调节因子 ,并可能是通过调节Th1/Th2细胞因子而发挥作用的 ,通过调控NO合成介导Th1/Th2免疫偏移可能是控制血吸虫卵肉芽肿病变的新途径  相似文献   

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Background: Celiac disease (CD) is commonly believed to be a predominantly Th1 disease. However, the exact balance between the Th1 and Th2 arms, as well as the correlation to clinical parameters, remains unclear. The aim was to assess the Th1/Th2 cytokine profile and its correlation to clinical parameters in active and non-active CD patients. Methods: Peak, total secretion and secretory pattern of the Th1 cytokines (IFN- &#110 and IL-2) and Th2 cytokines (IL-4 and IL-10) were determined in resting and stimulated peripheral blood mononuclear cells (PBMC) from 19 CD patients with active and non-active disease and 20 normal controls. Results: Peak and total secretion of IL-10 were significantly reduced in CD patients compared with normal controls. This was due to a persistently flat secretory pattern of IL-10 over time in CD patients. In addition, IFN- &#110 /IL-10 and the IL-2/IL-10 ratios of peak and total secretion were higher in patients than in controls. In contrast, peak, total secretion and secretory pattern of IL-2, IFN- &#110 and IL-4 were comparable in patients and controls as well as the IL-2/IL-4 and IFN- &#110 /IL-4 ratios. No difference in the cytokine secretion or Th1/Th2 ratio was found between active and non-active patients or between pediatric and adult patients. Conclusions: These data indicate that the Th1/Th2 balance in CD is shifted towards Th1 cytokines because of a down-regulated IL-10 secretion. The aberrant profile of cytokine secretion of these patients is not associated with clinical parameters and suggests an inherent defect in IL-10 secretion in CD.  相似文献   

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BALB/K mice are usually resistant to infection with the intestinal nematode parasite Trichuris muris and exhibit a Th2 dominated (IL-5, IL-9) response. Conversely in B10.BR mice, which are unable to expel T. muris, Th1 type (IFN-gamma producing) cells predominate. We have manipulated the course of infection in these two strains of mice such that the period of host-parasite contact is extended in the former and curtailed in the latter. Extension of host-parasite contact in BALB/K mice beyond normal (day 21) resulted in the modulation of cytokines produced by in vitro concanavalin A (Con-A) stimulated MLNC away from IL-5 and IL-9 (Th2-type cytokines) in favour of the Th1-type cytokine IFN-gamma. Curtailment of host parasite contact in B10.BR mice to less than 21 days resulted in elevated production of IL-5 and IL-9 by MLNC in the absence of elevated IFN-gamma levels. Thus modulation of expulsion phenotype also modulates cytokine production by T-cells in the MLN draining the site of infection, with a Th2 response being associated with resistance and a Th1 type response with the inability to expel the parasite. Mechanisms by which the modulated cytokine profiles arise are discussed.  相似文献   

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目的观察B7-1激发型mAb的体内注射对日本血吸虫感染小鼠Th1/Th2免疫偏移的影响及对虫卵肉芽肿病变的调节作用,探讨干预共刺激信号调控Th1/Th2免疫偏移控制血吸虫虫卵肉芽肿病变的新途径。方法小鼠感染日本血吸虫尾蚴后4w给予腹腔内注射B7-1激发型mAb,于6、8wk摘眼球取血收集血清,用ELISA双抗体夹心法测定血清中抗体IgGI、gG1I、gG2a的水平;同时取脾淋巴细胞培养72h,同法测定培养上清中细胞因子IFN-γ和IL-4的表达水平;并且检测感染小鼠虫卵肉芽肿体积。结果B7-1激发型mAb能显著下调感染小鼠血清IgG水平,并能显著上调IFN-γ的表达水平,下调IL-4的表达水平,同时能使虫卵肉芽肿体积显著减小。反映Th1/Th2免疫偏移的IgG1/IgG2a有下降趋势。结论B7-1激发型mAb能调节Th1/Th2免疫应答,诱导免疫反应向Th1方向偏移,从而为控制日本血吸虫虫卵肉芽肿病变的免疫治疗新途径提供了实验依据。  相似文献   

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Aims/hypothesis: Sirolimus and tacrolimus are immunosuppressive drugs that prevent rejection of pancreatic islet allografts transplanted into patients with Type I (insulin-dependent) diabetes mellitus. This study aimed to determine whether sirolimus and tacrolimus can prevent autoimmune beta-cell destruction, and if so, what the mechanisms of action are. Methods: Sirolimus and tacrolimus were given separately and together to female non-obese diabetic (NOD) mice from age 12 to 35 weeks. Diabetes incidence was determined and pancreatic insulitis and insulin content were measured. Sirolimus and tacrolimus were also given separately and together to diabetic NOD mice from the time of syngeneic islet transplantation until the reappearance of hyperglycaemia. Islet grafts were examined by RT-PCR assay for expression of interferon (IFN)-γ, interleukin (IL)-2, IL-4, IL-10 and transforming growth factor (TGF)-β1. Results: Low doses of sirolimus (0.1 mg/kg) and tacrolimus (0.1 mg/kg) were synergistic in reducing insulitis, preserving pancreatic insulin content and preventing diabetes in female NOD mice (8 % diabetes incidence at 35 weeks vs 66 % in vehicle-treated mice). Also, the combination of sirolimus and tacrolimus prolonged syngeneic islet graft survival (median 34 days vs 13 days for vehicle-treated mice). Islet grafts from sirolimus plus tacrolimus-treated mice expressed significantly decreased mRNA contents of Th1-type cytokines (IFN-γ and IL-2) and the highest ratio of TGF-β1/IFN-γ mRNA. Conclusion/interpretation: These findings suggest that combination therapy with sirolimus and tacrolimus prevent autoimmune beta-cell destruction by upregulating expression of the immunoregulatory cytokine, TGF-β1 and reducing Th1 cytokines (IFN-γ and IL-2) expressed in the islets. Low-dose sirolimus and tacrolimus combination therapy could warrant consideration for prevention or early treatment of human Type I diabetes. [Diabetologia (2002) 45: 224–230] Received: 20 August 2001 and in revised form: 29 October 2001  相似文献   

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Abstract:  Islet transplantation has been established as a potential therapy for type 1 diabetes. However, inflammation, allorejection, and on-going autoimmune damage contribute to early graft loss and failure of islet transplantation. Melatonin is the major secretory product of the pineal gland during the dark period of each day and displays multifunctional properties including the regulation of circadian and seasonal rhythms, antioxidation reactions and immune modulation. Based on the immunosuppressive properties of melatonin, we investigated whether melatonin treatment prolonged the survival of islet grafts in non-obese diabetic (NOD) mice. The mean islet graft survival time was 7.33 ± 1.51 and 7.75 ± 2.66 days in untreated controls and in the solvent-treated animals, respectively. Strikingly, the mean survival time of islet grafts in recipients treated with melatonin (200 mg/kg/bw) was 17 ± 7.76 days. Moreover, melatonin treatment reduced the proliferation of splenocytes in NOD mice. Using a T1 and T2 double transgenic mouse model, we found that T helper 1 (Th1) cells in mice treated with melatonin were significantly decreased. The reduction of Th1 cells and T cell proliferation may result from an increase in the immunosuppressive cytokine IL-10. Our results indicate that melatonin treatment suppresses autoimmune recurrence by inhibiting the proliferation of Th1 cells in NOD mice and thus prolongs the survival of syngeneic islet grafts.  相似文献   

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目的观察拉米夫定(LAM)治疗前后患者血清Th1/Th2比值的动态变化。方法用酶联免疫吸附(ELISA)方法分别检测60例慢性乙型肝炎患者在拉米夫定治疗前,治疗后第3、6、9、12月时的血清IFN-γ和IL-4水平。选取20名健康献血员作为正常对照。结果LAM治疗前ALT高水平组IFN-γ水平及IFN-γ/IL-4比值较高,完全应答率较高,无应答率较低;治疗后完全应答组IFN-γ/IL-4水平接近或高于对照组,部分应答组和无应答组IFN-γ/IL-4水平低于对照组。结论拉米夫定治疗慢性乙型肝炎可增加Th1类细胞因子IFN-γ分泌,抑制Th2类细胞因子IL-4分泌,治疗后Th1/Th2平衡的恢复与抗病毒疗效有关。T细胞免疫功能的恢复是抗病毒治疗的关键之一。  相似文献   

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目的观察急性冠状动脉综合征(acute coronary,syndromes,ACS)患者应用阿托伐他汀后外周血中1型辅助性T细胞(Th1)和2型辅助性T细胞(Th2)的频率及其相关细胞因子的变化,探讨他汀类药物对ACS患者辅助性T细胞分化的影响。方法选择ACS患者73例,随机分为安慰剂组(36例)和阿托伐他汀组(37例),入选实验后即刻,1、3、14天抽取外周血,检测Th1和Th2频率及其相关细胞因子的浓度,其中Th1相关细胞因子为干扰素γ、白细胞介素2,Th2相关细胞因子为白细胞介素4、白细胞介素10。结果安慰剂组与阿托伐他汀组即刻外周血Th1和Th2频率及其相关细胞因子水平比较,差异无统计学意义(P0.05);阿托伐他汀组外周血1、3、14天Th1相关细胞因子干扰素γ、白细胞介素2水平较安慰剂组明显降低(P0.05),而Th2相关细胞因子白细胞介素10水平较安慰剂组明显升高(P0.05);阿托伐他汀组1、3、14天Th1频率较安慰剂组明显降低(P0.05),而Th2频率两组间差异无统计学意义(P0.05)。结论阿托伐他汀通过调节Th1和Th2亚群分化失衡,抑制炎性反应,提示他汀类药物对ACS患者有更广泛的保护作用。  相似文献   

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Current evidence suggests that increased expression of Th1-associated cytokines is important for immune-mediated eradication of hepatitis C infection, while an increase in Th2-associated cytokines is associated with persistence of infection. In this study we evaluated the effects of thymosin-alpha1 (TA1), a naturally occurring thymic peptide, and interferon-alpha (IFN-alpha) on cytokine production in peripheral blood mononuclear cells from untreated patients with chronic hepatitis C. We examined the effect of incubation with TA1, IFN-alpha, or both, on production of Th1-associated cytokines (IL-2, IFN-gamma), Th2-associated cytokines (IL-4, IL-10), and synthesis of the antiviral protein 2',5'-oligoadenylate synthetase. TA1 treatment induced a significant increase in production of IL-2 and 2',5'-oligoadenylate synthetase. Smaller increases were also seen after treatment with IFN-alpha, while incubation with TA1 and IFN-alpha together led to an additive or synergistic effect. Incubation with TA1 resulted in a decrease in IL-4 and IL-10, whereas IFN-alpha increased these cytokines. The addition of TA1 to IFN-alpha significantly reversed this IFN-alpha-induced increase. Hence, TA1 treatment could benefit patients with hepatitis C infection by increasing the Th1-type response, fundamental for sustained clearance of hepatitis C; and by decreasing the Th2-type response, associated with persistence of viraemia.  相似文献   

20.
目的 在mRNA 水平对山羊Th1/Th2型细胞因子进行定量分析,建立山羊Th1/Th2型细胞因子实时荧光定量检测方法。方法 根据GenBank山羊Th1(IL-2和IFN-γ)和Th2(IL-4、IL-6和IL-10)细胞因子基因保守序列设计引物,以标准阳性质粒为模板分别进行荧光定量PCR反应的标准曲线、溶解曲线建立。结果 山羊Th1/Th2细胞因子实时荧光定量检测方法Ct值与标准品呈良好的线性关系,R2均大于0.985,所有稀释度标准品模板出现特异性熔解峰;利用N1蛋白缺失的重组山羊痘病毒(△N1L株)与山羊痘AV41株感染山羊外周血淋巴细胞进行IL-4和IFN-γ mRNA 表达水平检测,△N1L株与山羊痘AV41株均能能够刺激机体IL-4和IFN-γ细胞因子,但二者差异无统计学意义(t=3.333,P>0.5)。结论 本研究建立山羊Th1/Th2细胞因子实时荧光定量检测,为山羊痘基因工程疫苗的研究奠定基础。  相似文献   

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