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1.
目的观察活的/热致死发酵乳杆菌对牛乳β-乳球蛋白(BLG)致敏小鼠Th1/Th2细胞平衡、血清抗体水平及T淋巴细胞亚群数量的影响,探讨其缓解过敏反应的作用。方法用牛乳BLG和弗氏佐剂的混合液腹腔注射诱发Balb/c小鼠致敏,建立动物过敏模型。将实验动物随机分为空白组、致敏组、活的与热致死发酵乳杆菌组。采用ELISA法测定各组小鼠血清总IgE和BLG特异性IgE含量。体外分离培养各组小鼠脾淋巴细胞,采用ELISA法检测细胞上清液中Thl型细胞因子(IL-12、IFN-γ)和Th2型细胞因子(IL-4)的水平,采用流式细胞术检测脾淋巴细胞中CD3+、CD4+和CD8+的百分含量。结果与致敏组相比,活的/热致死发酵乳杆菌组小鼠的IFN-γ/IL-4比值(代表Thl/Th2细胞平衡)显著增高(P<0.05);血清总IgE和BLG特异性IgE水平显著降低(P<0.05);脾淋巴细胞中的CD4+细胞比例升高,CD4+/CD8+比值得到优化。特别是热致死的发酵乳杆菌组抑制IL-4分泌的效果显著优于活菌组(P>0.05),且该组的抗体水平和CD4+/CD8+比值与空白组相比无差异(P>0.05)。结论发酵乳杆菌干预可改善小鼠的BLG过敏症状,其作用可能与促进Thl占优势的Thl/Th2细胞平衡,阻断IgE分泌及平衡T淋巴细胞亚群数量相关。  相似文献   

2.
目的:探讨细胞毒性T淋巴细胞相关抗原4免疫球蛋白(CTLA4 Ig)基因修饰的树突状细胞(CTLA4 Ig-DCs)体外对Th1/Th2平衡的影响。方法:通过腺病毒载体将目的基因(CTLA4 Ig)转染至小鼠骨髓来源的树突状细胞(DC)。采用流式细胞术(FCM)检测DC表面分子和胞内CTLA4 Ig的表达;采用混合淋巴细胞反应检测DC刺激同种异体T细胞的能力,ELISA法检测DC抗原提呈反应中Th1和Th2类细胞因子IFN-γ和IL-4分泌水平。结果:CTLA4 Ig基因成功转染至DC,转染率约为80%,制备的CTLA4 Ig-DCs稳定表达CTLA4Ig,表面分子CD86呈现低表达;CTLA4 Ig-DCs可有效抑制T细胞增殖,降低抗原提呈反应上清中IFN-γ和IL-4的分泌,并增加IFN-γ/IL-4比值。结论:通过腺病毒将CTLA4 Ig转染DC并且高效表达,可有效降低DC表面CD86分子,抑制同种异体T细胞反应,并能影响体外Th1/Th2水平。  相似文献   

3.
目的:观察热致死的发酵乳杆菌对牛乳β-乳球蛋白(BLG)致敏小鼠Th1/Th2细胞平衡、血清抗体水平及T细胞亚群数量的影响,探讨其缓解过敏反应的作用。方法:用牛乳BLG和弗氏佐剂的混合液腹腔注射诱发BALB/c小鼠致敏,建立动物过敏模型。将实验动物随机分为空白组、致敏组和不同剂量的热致死发酵乳杆菌组。采用ELISA法测定各组小鼠血清总IgE、BLG特异性IgE和总IgG含量。体外分离培养各组小鼠脾细胞,采用ELISA法检测细胞上清液中Th1型细胞因子(IL-12、IFN-γ)和Th2型细胞因子(IL-4)水平,采用流式细胞术检测脾淋巴细胞中CD3+、CD4+和CD8+T百分含量。结果:发酵乳杆菌组小鼠脾细胞培养上清液中IFN-γ/IL-4比值为13.53,显著高于致敏组的3.34(P<0.05);血清总IgE、BLG特异性IgE和总IgG水平显著降低(P<0.05);脾细胞中CD3+和CD4+T细胞比例升高,CD4+/CD8+比值趋近正常组。特别是高剂量的热致死发酵乳杆菌组小鼠脾细胞培养上清液中抑制IL-4分泌的效果显著优于致敏组(P>0.05),且该组小鼠血清的抗体水平和CD4+/CD8+比值与空白组相比无差异(P>0.05)。结论:热致死的发酵乳杆菌干预可改善小鼠的BLG过敏症状,其作用可能与促进Th1占优势的Th1/Th2细胞平衡,阻断IgE、IgG分泌及平衡T细胞亚群数量相关。  相似文献   

4.
为研究两种i Gb3类似物(化学修饰的糖脂4′″-dh-i Gb3和4-HO-i Gb3)对NKT细胞Th1/Th2型细胞因子分泌的影响。采用流式细胞术检测经腹腔注射两种i Gb3类似物后C57BL/6小鼠脾脏NKT细胞数量的变化以及NKT细胞胞内IFN-γ和IL-4的表达水平;用Real-ti me PCR方法检测体外培养的脾脏淋巴细胞与i Gb3类似物共孵育后IFN-γ和IL-4的mRNA表达水平,并用ELISA方法检测孵育上清中IFN-γ和IL-4的含量。结果显示:与i Gb3组相比,经两种i Gb3类似物体内刺激后脾脏NKT细胞的数量都没有显著性变化。糖脂4-dh-i Gb3能够较i Gb3更强地诱导脾脏NKT细胞胞内IFN-γ的表达,也能够上调体外培养的脾脏淋巴细胞IFN-γ的mRNA水平及IFN-γ的分泌,而IL-4在所检测的各个水平上都没有显著性变化。提示化学修饰的糖脂4′″-dh-i Gb3能够诱导C57BL/6鼠脾脏NKT细胞Th1型细胞因子的分泌,而并不显著影响Th2型细胞因子的分泌,从而诱导Th1/Th2型细胞因子平衡向Th1方向偏移。  相似文献   

5.
王美红  陈同辛 《现代免疫学》2003,23(5):359-360,f003
T-bet是属于T-box家族的新型转录因子,选择性地表达于Th1细胞,作为Th1特异的转录因子能诱导IFN-γ的产生,在Th1细胞的分化中起着决定性的作用。T-bet是IFN-γ基因强有力的转录激活剂,又能诱导并保持IL-12Rβ2的表达,且能将分化中的效应性Th2和已完全分化的Th2逆转为Th1,伴随产生大量的IFN-γ,并抑制IL-4、IL-5、IL-13等Th2型细胞因子的产生。T-bet在T细胞活化过程中能被IFN-γ诱导而上调;通过STAT1依赖的途径,TGF-β能通过抑制T-bet而抑制Th1分化。T-bet与Th1/Th2相关疾病的联系正日益受到关注。  相似文献   

6.
目的 采用病例对照探讨全氟化合物(PFAAS)暴露与儿童哮喘及Th1型细胞因子白细胞介素(IL)-2,干扰素(IFN)-γ和Th2型细胞因子(IL-4,IL-5)分泌水平的关系.方法 选择231名台北医院就诊的哮喘儿童作为病例组,来自社区的225名自然儿童作为对照组.采用双抗体酶联免疫吸附实验(ELISA)试剂盒检测儿童血清中细胞因子IL-2、IFN-γ、IL-4和IL-10的分泌水平;高效液相色谱仪分析血清中全氟辛烷磺酸(PFOS)和全氟辛酸(PFOA)水平.结果 哮喘儿童机体PFOS(33.9μg/L比28.9 μg/L)和PFOA(1.2μg/L比0.5 μg/L)暴露负荷显著的高于对照组儿童,且随着机体PFAAs的增高,儿童患有哮喘的风险呈增高趋势.对哮喘儿童而言,血清PFAAs水平与Th1型细胞因子(IL-2,IFN-γ)存在显著的负相关,而与Th2型细胞因子(IL-4,IL-5)呈正相关关系.结论 PFOS暴露可诱导机体免疫应答平衡紊乱,并向Th2型免疫应答极化.  相似文献   

7.
探讨慢性乙肝患者树突状细胞(dendritic cells,DC)对CD4+Th细胞亚群分化的影响。分离慢性乙肝患者外周血单个核细胞(PBMC),以rhIL-4(50 ng/ml)、rhGM-CSF(10 ng/ml)和rhTNF-α(100 u/ml)诱导培养DC。以流式细胞仪检测DC表面CD1a、CD83、CD80、CD86、HLA-DR分子表达情况。MTT法检测DC刺激同种异体淋巴细胞增殖能力。免疫磁珠分离外周血CD4+T细胞亚群,PMA+Ionomycin刺激后胞内荧光染色,流式细胞仪检测辅助性T细胞(helper T cell,Th)内特征性细胞因子IFN-γ/IL-4以判断Th1/Th2分化。ELISA法检测DC或Th细胞培养上清中IL-6、IL-12、IFN-γ和IL-4的含量。结果:慢性乙肝患者的DC表达CD1a、CD83、CD80、CD86、HLA-DR分子水平明显低于正常人(P<0.01);培养至第7天,慢性乙肝患者DC分泌的IL-12水平低于正常人(P<0.01),而分泌的IL-6水平增高(P<0.05)。与正常人相比,慢性乙肝患者外周血中Th1细胞占CD4+T细胞的百分比较低(P<0.01),其Th细胞培养上清中IFN-γ的量也较低(P<0.01)。患者DC与同种异体的健康人Th细胞共培养,刺激Th1型细胞因子IFN-γ产生的能力低于正常人(P<0.01)。慢性乙肝患者体内DC功能的异常可能导致了外周血Th1细胞分化不足。  相似文献   

8.
CCK-8对KLH免疫小鼠脾细胞Th1/Th2平衡的影响   总被引:2,自引:1,他引:1       下载免费PDF全文
目的: 探讨八肽胆囊收缩素(CCK-8)对Th1/Th2平衡的调节作用。方法: 给予BALB/c小鼠钥孔戚血蓝蛋白(KLH)免疫同时体内给予不同剂量的CCK-8,酶联免疫吸附试验(ELISA)检测其脾细胞培养上清中Th1型细胞因子γ-干扰素(IFN-γ)、白细胞介素-2(IL-2)和Th2型细胞因子白细胞介素-4(IL-4)、白细胞介素-5(IL-5)水平,逆转录聚合酶链式反应(RT-PCR)法检测脾细胞中IFN-γ、IL-2、IL-4、IL-5 mRNA表达;ELISA法检测血清中Th1型抗KLH抗体IgG2a和Th2型抗KLH抗体IgG1水平。结果: ①KLH免疫使小鼠脾细胞分泌Th1/Th2型细胞因子水平明显增高,mRNA表达增高,KLH免疫同时给予CCK-8可使脾细胞培养上清中IFN-γ、IL-2含量进一步增加和IFN-γ、IL-2mRNA表达增高,而使IL-4、IL-5含量降低,IL-4、IL-5 mRNA表达减低和降低IL-4/IFN-γ比值。②KLH免疫小鼠血清中IgG2a、IgG1发生不同程度增高,CCK-8可使其血清中IgG1水平减低而使IgG2a水平增高。结论: CCK-8可促进KLH免疫小鼠体内Th1反应,使Th2优势反应向Th1方向转变。  相似文献   

9.
米非司酮通过增强母-胎界面Th1型偏移导致流产   总被引:1,自引:0,他引:1  
目的:探讨米非司酮对母胎界面Th1/Th2型细胞因子动态平衡的影响.方法:将63例早孕期妇女随机分为2组,一组一次服用米非司酮200 mg,另一组为对照组,收集其蜕膜组织.应用免疫组化法,评价Th1型细胞因子(IL-2、IFN-γ)、Th2型细胞因子(TGF-β2、IL-4)的表达.结果:正常妊娠时,在母-胎界面Th2型细胞因子(IL-4)以及TGF-β2的表达较高;Th1型细胞因子(IL-2、IFN-γ)的表达较低,尤其是IL-2.服用米非司酮后,蜕膜Th1型细胞因子(IL-2、IFN-γ)表达显著升高;而母-胎界面Th2型细胞因子(IL-4)以及TGF-β2的表达无明显变化.结论:米非司酮打破了正常妊娠时母胎界面Th2型免疫优势;显著升高Th1型细胞因子(IL-2、IFN-γ)表达,形成了Th1型免疫偏离,导致流产的发生.  相似文献   

10.
目的:探讨MBP对小鼠T细胞的调节作用.方法:采用淋巴细胞分层液分离小鼠脾脏淋巴细胞,在体外用MBP刺激淋巴细胞,通过MTT法测定淋巴细胞增殖反应;ELISA检测脾细胞培养上清中细胞因子的分泌水平;MBP免疫小鼠后,ELSPOT检测MBP刺激脾淋巴细胞分泌IFN-γ的细胞频数;免疫组化检测MBP与T细胞的结合作用.结果:MBP以剂量依赖关系促进小鼠淋巴细胞的增殖,促进淋巴细胞分泌IL-2和IFN-γ,轻微抑制IL-4的分泌;ELSPOT检测细胞分泌IFN-γ结果显示,MBP可诱导特异性Th1活化,也可刺激非特异性Th1活化;免疫组化结果显示,抗MBP抗体可与经MBP刺激的淋巴细胞发生反应,阳性细胞占总淋巴细胞的37.7%,当MBP采用 1∶2 000抗MBP抗体中和后,再与淋巴细胞反应,结果未见阳性细胞.结论:MBP可作用于淋巴细胞诱导非特异性Th1活化,也可通过免疫诱导大量特异性Th1活化;MBP可作为新的免疫增强剂开发利用.  相似文献   

11.
Mercuric chloride (HgCl2) has contrasting effects on different rat strains: susceptible strains, e.g. Brown Norway (BN) develop polyclonal B cell activation, multiple autoantibodies and widespread tissue injury. Lewis (LEW) rats are resistant: no autoimmune response occurs after HgCl2; instead, there is immunosuppression. We have previously shown, by fully quantitative polymerase chain reaction (PCR), up-regulation of interleukin-4 (IL-4) gene expression in HgCl2-treated BN rats, implicating Th2 cells in the autoimmune syndrome. Involvement of the reciprocal Th1 subset, producing interferon-γ (IFN-γ), in resistance of LEW rats to HgCl2 has been suggested. We now report extensive analysis of Th1 and Th2 cytokine gene expression in spleen and lymph nodes of susceptible (BN) and resistant (LEW) rats after HgCl2. IL-4 and IFN-γ were analyzed by quantitative PCR, other cytokines were assessed using semiquantitative PCR: the relative merits of these two techniques are discussed. We show pronounced up-regulation of IL-4 and more modest up-regulation of IFN-γ in BN rats, but no up-regulation of either in LEW rats. Baseline levels of IFN-γ were higher in LEW rats. Semi-quantitative PCR showed increased expression of IL-2, IL-6 and IL-10 in BN; in LEW rats only IL-10 was increased. There was no marked change in IL-5, IL-13 or transforming growth factor-β (TGF-β) in either strain. These data further support the key role of IL-4 in HgCl2-induced autoimmunity, and suggest that failure of up-regulation of IL-4, together with higher baseline IFN-γ expression, accounts for resistance of LEW rats to HgCl2. However, neither IFN-γ nor TGF-β can be implicated in HgCl2-induced immunosuppression in the LEW rat in vivo: our data suggest a role for IL-10 in this phenomenon.  相似文献   

12.
13.
Mast cells (MCs) play an important role in the regulation of protective adaptive immune responses against pathogens. However, it is still unclear whether MCs promote such host defense responses via direct effects on T cells or rather by modifying the functions of antigen-presenting cells. To identify the underlying mechanisms of the immunoregulatory capacity of MCs, we investigated the impact of MCs on dendritic cell (DC) maturation and function. We found that murine peritoneal MCs underwent direct crosstalk with immature DCs that induced DC maturation as evidenced by enhanced expression of costimulatory molecules. Furthermore, the MC/DC interaction resulted in the release of the T-cell modulating cytokines IFN-γ, IL-2, IL-6 and TGF-β into coculture supernatants and increased the IL-12p70, IFN-γ, IL-6 and TGF-β secretion of LPS-matured DCs. Such MC-"primed" DCs subsequently induced efficient CD4+ T-cell proliferation. Surprisingly, we observed that MC-primed DCs stimulated CD4+ T cells to release high levels of IFN-γ and IL-17, demonstrating that MCs promote Th1 and Th17 responses. Confirming our in vitro findings, we found that the enhanced disease progression of MC-deficient mice in Leishmania major infection is correlated with impaired induction of both Th1 and Th17 cells.  相似文献   

14.
Cytokine production in the spleens of mice infected with the protozoan parasite Trypanosoma cruzi was analyzed in three models which differ in the outcome of the infection. Using immunocytochemical techniques to detect cytokine-producing cells, the production of type 1 [interleukin-2 (IL-2) and interferon (IFN)-γ], type 2 (IL-4, IL-5, IL-10), inflammatory [tumor necrosis factor (TNF)-α, IL-1α, IL-6] and regulatory (transforming growth factor-β) cytokines were examined. With the exception of IL-4 and IL-5, cells producing all of the cytokines assayed were detected in both the resistant and susceptible models of T. cruzi infection. Cells producing IL-4 and IL-5 were not detected until later in infection in the resistant mice (>34 days), at about the time animals of the susceptible strain succumb to the infection. Mice of the susceptible model showed a slight delay in the appearance of cells producing the type 1 cytokines IL-2 and IFN-γ and an earlier appearance of TNF-producing cells, in comparison to resistant mice. Cells producing IL-2 or IL-10 were transient in their appearance in the spleen while cells producing IL-1, IL-4, IL-5, IL-6, IFN-γ, TNF, or TGF-β were first detectable in either the acute or post-acute stage of the infection and persisted up to 700 days post infection in two different resistant models of the infection. Cells producing IFN-γ, TNF-α and TGF-β were particularly numerous even very late in the infection. Double-staining techniques were used to show that the vast majority of the IFN-γ-producing cells in the spleen were CD4?, CD8? α/β TCR+ T cells. This study confirms the transience of IL-2 production in the acute stage of T. cruzi infection and the persistent and simultaneous production of type 1 and type 2 cytokines during the late-acute and chronic stages of the infection. Susceptibility or resistance to T. cruzi infection does not associate with a Th2 pattern of cytokine production in the three models examined in this study. The overlapping pattern of type 1 and type 2 cytokine-producing cells in both the acute and chronic stages of T. cruzi infection demonstrates that longterm infections do not necessarily lead to a dominance of either type 1 or type 2 cytokine production.  相似文献   

15.
目的 探讨CD4~+细胞亚群[Th1、Th2、CD4~+CD25~+Foxp3~+调节性T细胞(Tr)及Th17细胞]在1型糖尿病(TIDM)患儿免疫发病机制中的作用.方法 新诊断TIDM患儿20例,同年龄对照组(Ctrl组)20例.用流式细胞术检测外周血Th1、Th2、Tr及Th17细胞比例.荧光定量PCR(real-time PCR)检测Th1、Th2、Tr、Th17细胞转录因子T-bet、GATA-3、Foxp3、ROR-γt、IFN-、IL-4、IL-10、IL-17A、CTLA-4、GITR等细胞因子和负性调节因子mRNA表达;应用酶联免疫吸附方法(ELISA)检测IFN-γ、IL-4、TGF-β、IL-6血浆水平.结果 (1)与正常对照组相比,TIDM患儿Th1细胞比例明显增高(P<0.01),Th2细胞比例明显降低(P<0.01),Tr和Th17细胞比例与正常对照组相比无明显差别(P>0.05).(2)Th1细胞转录因子及细胞因子T-bet、IFN-γ较正常对照组明显升高(P<0.01);Th2细胞转录因子及细胞因子GATA-3、IL-4明显降低(P<0.01);Tr细胞转录因子Foxp3表达与正常对照组相比差异无统计学意义(P>0.05),Tr细胞相关细胞因子及负性调节因子IL-10、CTLA-4及GITR基因表达明显低于对照组(P<0.01);Th17细胞转录因子ROR-γt及细胞因子IL-17A基因表达与对照组相比无明显差异(P>0.05);(3)TIDM患儿外周血IFN-γ浓度明显增高,IL-4明显降低,TGF-β、IL-6浓度无明显改变(P>0.05).结论 TIDM患儿Th1/Th2失衡,加上Tr细胞抑制功能缺陷,可能导致TIDM严重细胞免疫功能紊乱.  相似文献   

16.
Background and aim: We investigated the effect of zinc oxide (ZnO) on Th1 and Th2 immune responses in mice.

Material and methods: Mice were intraperitoneally administered with ovalbumin (OVA) with or without varying doses of ZnO (day 0). On day 21, anti-OVA IgG, IgG2a, IgG1, and IgE antibodies in sera, OVA-specific proliferative responses of spleen cells, and production of Th1 cytokines including IFN-γ as well as Th2 cytokines such as IL-4 and IL-5 were measured.

Results: The results showed that administration of OVA with ZnO was followed by greater increases in anti-OVA IgG and the antigen-specific splenocyte proliferation compared to that of OVA alone. The production of anti-OVA IgG1 and IgE and secretion of IL-4 and IL-5 were markedly enhanced by ZnO. The enhancing effect of ZnO on these Th2 responses was as strong as aluminium hydroxide (Alum) that was widely used as an adjuvant. In contrast, treatment with OVA plus ZnO failed to affect production of anti-OVA IgG2a as well as IFN-γ. It was also observed that ZnO had a stimulating effect on the secretion of the proinflammatory cytokine IL-17 from a new lineage of effector Th cells.

Conclusion: These results suggest that ZnO appears to have an adjuvant effect on the immune system, especially Th2 but not Th1 immune responses.  相似文献   

17.
Stimulation of murine CD4+ T cells with staphylococcal enterotoxin B (SEB) results in the preferential development of T helper (Th) 1 cells [i.e. high interferon (IFN)-γ and low interleukin (IL)-4, IL-5 and IL-10]; whereas in response to plate-bound anti-CD3 or anti-T cell receptor-αβ, Th1 as well as Th2 cells develop. In the present study, we examined the mechanism which is responsible for the selective Th1 development in the SEB system. The addition of IL-4 resulted in a strong development of Th2 cells showing that SEB stimulation can result inTh2 differentiation. Co-stimulation with anti-CD28 was insufficient in this regard. Lack of Th2 development in the SEB system was in part due to the inhibitory effect of endogenously produced transforming growth factor-β (TGF-β), because anti-TGF-β allowed the development of Th2 cells. Similarly, TGF-β inhibited Th2 development and stimulated Th1 development in the anti-CD3 system. This shift was only partially prevented by also including IL-4 in the cultures. The effects of TGF-β could only partially be explained by stimulation of IFN-γ or inhibition of IL-4 as intermediatory cytokines: (1) TGF-β stimulated Th1 development even in the presence of anti-IL-4 and anti-IFN-γ, and (2) a strong inhibitory effect of anti-TGF-β on Th1 development was still observed when anti-IL-4 and IFN-γ were simultaneously added to the cultures. It is concluded that SEB favors Th1 development by stimulation of TGF-β production. Inhibition of Th2 development by TGF-β is due, in part, to inhibition of IL-4 and stimulation of IFN-γ, and, in part, to a direct effect of TGF-β on the responding T cells.  相似文献   

18.
The Th1/Th2 profile that follows human vaccination may profoundly influence the subsequent course of disease after infection. However, the ability to detect IL-4 has been limited outside trials of live vaccination. By using methods in which memory effector cells are allowed to antigenically expand by short term culture, followed by low-dose mitogenic stimulation, we have been able to follow the Th1/Th2 profile in HIV-1?volunteers enrolled in two phase I studies of HIV immunogens (a recombinant gp120 and a multivalent, octomeric V3 loop peptide). Antigen-specific interferon-gamma (IFN-γ) could be detected in primary stimulation, but IL-4 was observed only after antigenic expansion and restimulation. In both of these studies the responses after initial immunizations were dominated by IFN-γ, with IL-4 appearing only after multiple rounds of immunization, and IL-4 was temporally related to antibody production. Concomitant with the IL-4 production, the amount of supernatant IFN-γ declined. Antigen-specific IL-10 was not detected in either study. Such techniques, which have been shown to correlate with outcomes in immunotherapy, may prove useful as future surrogates of human vaccine response.  相似文献   

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