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1.
热休克蛋白60对小鼠树突状细胞功能影响体外研究   总被引:1,自引:0,他引:1  
目的:探讨动脉粥样硬化中重要炎性物质——热休克蛋白60(HSP60)体外对小鼠树突状细胞(mDC)功能影响.方法:小鼠骨髓提取DC,体外培养成熟后与两种浓度mHSP60孵育,动态观察DC突起改变;流式细胞仪检测孵育前后mDC表面标志改变;MLR测定孵育前后mDC刺激功能变化;ELISA法测定MLR上清液中细胞因子浓度.结果:孵育后,mDC突起增加明显;CD11c^+、CD80及CD86表型显著增加;淋巴细胞刺激功能明显增强;分泌细胞因子IL-12、IFN-γ增加(P<0.01)而IL-4增加不明显(P>0.05),IFN-γ/IL-4比值升高.结论:mHSP60体外可以促进mDC功能,作用呈剂量依赖性.  相似文献   

2.
为了探讨树突状细胞(DC)分泌的外体(Dex)在诱导T细胞免疫耐受中的作用,体外研究采用供体Dex降低同种异体移植排斥的可能性。从正常人外周血单个核细胞中诱导培养未成熟DC(imDC),用TGF-β1联合IL-10诱导调节性DC,LPS诱导DC成熟。采用流式细胞术方法观察TGF-β1和IL-10对DC表型、吞噬功能的影响;采用超速离心和超滤的方法提纯Dex;Western blot方法检测imDC分泌的Dex(imDex)与调节性DC分泌的Dex(rDex)表达的相关分子;通过CCK-8法分析异源iDex和mDex在混合淋巴细胞反应(MLR)中的生物学功能,并比较rDex与iDex诱导免疫耐受的能力。结果显示,TGF-β1和IL-10可下调DC表面的共刺激分子CD80、CD83、CD86的表达,并诱导调节性DC分泌更多的rDex;异源的mDC分泌的Dex(mDex)在mDC存在时增强MLR,而异源的imDex在imDC存在时一定程度上抑制MLR,rDex诱导的抑制T细胞增殖作用显著强于iDex;rDex表达更多的FasL,提示TGF-β1和IL-10诱导的调节性DC分泌的rDex在免疫耐受中发挥重要作用,有望应用于同种异体移植抗免疫排斥。  相似文献   

3.
不稳定型心绞痛患者树突状细胞功能的研究   总被引:3,自引:0,他引:3       下载免费PDF全文
目的:研究不稳定型心绞痛患者(UAP)树突状细胞(DC)的功能。方法:分离14例UAP和11例正常人外周血单个核细胞(PBMC),在含粒细胞巨噬细胞集落刺激因子(GM-CSF)和白介素4(IL-4)的培养条件下制备DC。用流式细胞仪检测DC表面共刺激分子CD 86(B7-2)的表达;混合淋巴反应(MLR)检测DC对同种异体T淋巴细胞的刺激能力;ELISA法测定MLR上清液中的细胞因子。结果:与正常组比较,UAP者DC表面CD 86的表达明显增高;对T淋巴细胞刺激的能力增强;经DC刺激的淋巴细胞分泌致炎细胞因子(IL-1β,IL-6,TNF-α)增多,抑炎细胞因子(IL-10)减少。结论:UAP者DC的功能亢进,由此启动的T淋巴细胞的增殖和炎性细胞因子分泌可能是UAP发病的原因。  相似文献   

4.
用Ficoll密度离心及贴壁法获得外周血单个核细胞 (PBMC ) ,PBMC经细胞因子组合诱导分化成树突状细胞 (DC ) :GM CSF (10 0ng/ml)与IL 4 (5 0ng/ml)诱导 5d后 ,分别加入TNF α (10ng/ml)或rhsCD4 0L (2 μg/ml)继续培养 4d ;倒置显微镜下观察DC形态 ,免疫荧光标记和流式细胞术分析DC表型 (CD1a、CD80、CD83、HLA DR、CD14、CD16、CD19)及摄取FITC Dextran抗原的能力 ;3 H TdR掺入法检测DC刺激自体混合淋巴细胞体外增殖反应 (MLR )能力 ;ELISA法分析DC培养上清中IL 12的水平 ;Trans well细胞趋化实验检测DC对自体外周T淋巴细胞的趋化能力。发现经rhsCD4 0L刺激的DC表面分子 (CD1a、CD80、CD83、HLA DR )的表达水平高于经典的细胞因子组合组 (GM CSF +IL 4 +TNF α ) ,同时rhsCD4 0L刺激后的DC摄取FITC Dextran的能力下降而刺激自体MLR和分泌IL 12的能力明显提高 ;而且rhsCD4 0L诱导的DC表面趋化因子受体CXCR4的表达水平及对自体外周T淋巴细胞的趋化能力均强于TNF α或FL激发的DC。rhsCD4 0L在体外不仅具有显著的诱导DC分化 ,促进DC成熟的功能 ,而且经rhsCD4 0L作用的DC能更有效地激发T淋巴细胞  相似文献   

5.
目的:研究microRNA-27a(miR-27a)对脂多糖(Lipopolysaccharide,LPS)刺激的小鼠树突状细胞(Dendritic cell,DC)的成熟和细胞因子分泌的影响。方法:小鼠骨髓来源的未成熟树突状细胞(immature dendritic cell,im DC)转染miR-27a的模拟物(miR-27a mimics)后,用LPS刺激24 h,采用流式细胞仪检测其表面共刺激分子CD80、CD86及MHCⅡ表达,ELISA方法检测其上清中的IL-12p70及IL-10蛋白水平,RT-PCR方法检测其细胞内IL-12p40及IL-10 mRNA水平,混合淋巴细胞反应(MLR)检测其刺激T细胞增殖能力。结果:与未处理的im DC比较,LPS刺激24 h后的DC表面的共刺激分子CD80、CD86及MHCⅡ表达均显著增高(均P0.001);LPS刺激24 h后,与对照组比较,转染miR-27a mimics细胞的共刺激分子CD80、CD86及MHCⅡ表达均显著降低(均P0.001),且显著抑制IL-12分泌(P0.01)、促进IL-10分泌(P0.05),并显著减弱LPS刺激的DC促CD4+T细胞增殖的能力(P0.01)。结论:miR-27a影响小鼠树突状细胞的成熟以及细胞因子的分泌。  相似文献   

6.
目的:探讨姜黄素(Curcumin)诱导免疫耐受性人树突状细胞(Dendritic cell,DC)的效果。方法:聚蔗糖-泛影葡胺(ficoll-hypaque,F-H)密度梯度离心法获得健康人外周血单个核细胞(PBMC),在含有重组人粒-巨噬细胞集落刺激因子(rhGM-CSF)、重组人白介素4(rhIL-4)的培养基中培养6天。实验共分四组:①未成熟DC组(imDC组)、②姜黄素组(Curcumin,Cur组)、③姜黄素+脂多糖组(Cur+LPS组)、④脂多糖组(LPS组)。流式细胞术检测DC表型CD80、CD86、CD83及HLA-DR的表达情况和DC吞噬葡聚糖的能力,酶联免疫吸附法(ELISA)检测DC分泌白介素-12(IL-12)的能力,混合淋巴细胞反应(MLR)检测DC刺激同种异体T淋巴细胞增殖的能力。结果:Cur能够显著抑制DC共刺激分子CD80、CD86、CD83及HLA-DR的表达,并呈剂量依赖性,与imDC组比较差异无统计学意义;与LPS组比较,Cur+LPS组DC吞噬葡聚糖的阳性细胞百分率显著提高(P<0.05),而刺激同种异体T淋巴细胞增殖的能力则显著下降(P<0.05),IL-12的分泌量也显著下降(P<0.05)。结论:姜黄素能够抑制人树突状细胞的成熟,从而获得免疫耐受性的人树突状细胞。  相似文献   

7.
目的 探讨HBe Ag对LPS诱导小鼠骨髓源性树突状细胞(DC)成熟的影响。方法 体外诱导C57BL/6小鼠骨髓细胞分化成未成熟树突状细胞,经CD11c磁珠分选纯化后将DCs随机分为空白对照组、LPS刺激组、HBe Ag+LPS刺激组。流式检测DC表型变化,混合淋巴反应(MLR)检测DC促T淋巴细胞增殖能力,酶联免疫法(ELISA)检测细胞上清液中IL-12的分泌水平,Western blot检测p38磷酸化水平,并设置SB203580组为阳性对照探讨细胞IL-12分泌的可能调节机制。结果 LPS刺激未成熟DC引起细胞表面MHC-Ⅱ、CD86表达升高,刺激同种异体淋巴细胞增殖能力增强,IL-12分泌量增高。HBe Ag可抑制LPS促进DC表面MHC-Ⅱ、CD86表达升高和促淋巴细胞增殖能力增强的作用。LPS刺激DC可引起p38磷酸化水平升高,并呈时间依赖性;HBe Ag或SB203580预处理细胞再予LPS刺激,磷酸化p38表达和IL-12分泌较单纯LPS刺激组明显下降。结论 HBe Ag对LPS引起的树突状细胞的成熟有一定的抑制作用,且HBe Ag可能通过抑制p38MAPK信号通路下调LPS诱导的树突状细胞IL-12的产生。  相似文献   

8.
观察蛋氨酸脑啡肽(MENK)对巨噬细胞-粒细胞集落刺激因子(GM-CSF)诱导的小鼠骨髓来源树突状细胞(DC)成熟及TLR-4表达的影响,探讨蛋氨酸脑啡肽对小鼠骨髓来源DCs免疫功能的调节机制。体外制备小鼠骨髓细胞用GM-CSF协同MENK诱导培养7d后用RT-PCR法检测TLR-4的mRNA表达,用western-blot检测TLR-4蛋白的表达,同时用流式细胞仪(FACS)分析DC表型特征,混合淋巴细胞反应(MLR)检测DC的功能。结果显示MENK协同诱导组树突状细胞TLR-4和共刺激分子的表达高于正常对照组(P<0.01)和GM-CSF诱导组(P<0.05)并具有强的激发MLR的能力。提示MENK可以促进DC成熟及TLR-4的表达,增强DC免疫功能。  相似文献   

9.
目的通过体外实验研究烟草烟雾提取物(CSE)对小鼠髓样树突状细胞(mDC)成熟的影响及可能的机制。方法小鼠骨髓来源的单个核细胞加入粒-单集落刺激因子(GM-CSF)、白细胞介素-4(IL-4)和含100 mL/L胎牛血清的RPMI1640培养液诱导出可供实验用的高纯度的未成熟DC(iDC),分空白对照组和CSE刺激组;CSE刺激组按15 mL/L的终浓度加入CSE,两组继续培养24 h,流式细胞检测技术检测mDC的共刺激分子CD40、CD80、CD86和MHC-Ⅱ的表达。结果空白对照组的mDC低表达CD40、CD80、CD86和MHC-Ⅱ;CSE刺激后mDC表达CD40、CD80和MHC-Ⅱ比空白对照组明显增加,差异有统计学意义(P<0.05)。结论烟草烟雾提取物促进小鼠骨髓来源的mDC的CD40、CD80和MHC-Ⅱ的表达。  相似文献   

10.
目的 探讨不同抗原在体外活化慢性乙型肝炎患者外周血树突状细胞(DC)及诱导特异性T细胞应答的能力.方法 用无血清培养基从慢性乙型肝炎患者外周血中分离培养DC,在DC成熟前,分别加入HBsAg多肽、HBcAg多肽刺激,用流式细胞仪检测DC表型,用液闪计数仪观察DC对T细胞的增殖作用,用ELISA法检测混合淋巴细胞反应(MLR)中IL-12的分泌水平.结果 经HBcAg多肽刺激DC的CD86表达率为(92.20±5.18)%,明显高于HBsAg多肽刺激组(76.19±3.90)%和未加抗原组(62.37±4.24)%,P<0.01;经HBcAg多肽刺激组DC诱导同种异体静止T细胞增殖的能力每分钟液闪计数值cpm为34 326±3088,明显高于HBsAg多肽刺激组20 306±2897和单个核细胞组3454±409,P<0.01;经HBcAg多肽刺激组DC MLR中IL-12(348±42.8)ng/L,分别高于HBsAg多肽刺激组(226±30.6)ng/L和未加抗原组(116±15.6)ng/L,P<0.01.结论 使用HBcAg多肽刺激DC可比HBsAg多肽更有效地提呈病毒抗原,提高诱导特异性T细胞应答的能力.  相似文献   

11.
One successful approach to generate dendritic cells (DC) is to cultivate peripheral blood monocytes in fetal calf serum (FCS)-containing medium in the presence of granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin (IL)-4. Because the use of xenogenic proteins has to be strictly avoided for clinical applications, alternative protocols use human plasma instead of FCS. The aim of our study was to characterize DC generated in the presence of human plasma; moreover, we describe a novel protocol to generate DC directly from peripheral blood mononuclear cells (PBMC). DC generated from purified monocytes in the presence of 1% human plasma (HP-DC) and GM-CSF and IL-4 both in the allogenic mixed leukocyte reaction (MLR) and in the tetanus presentation assay were potent stimulators of T-cell proliferation. DC generated from PBMC were equally effective stimulators in the allogenic MLR as those generated from purified monocytes. When the immunophenotype of DC generated from FCS containing medium (FCS-DC) was compared to that of HP-DC, the surface expression of CD1a and CD80 was significantly lower in HP-DC. In contrast, the expression of CD83 and CD86 was significantly higher in HP-DC than in FCS-DC. The capacity of receptor mediated endocytosis and macropinocytosis was found to be significantly lower in HP-DC when compared to FCS-DC. The differences in the immunophenotype, macropinocytosis and endocytosis between the HP-DC and the FCS-DC were observed independently of the generation of the cells from PBMC or purified monocytes. Our data indicate that HP-DC are potent stimulators of T-cell proliferation and exhibit a characteristic phenotype of intermediate maturity. Moreover, DC can be directly generated from PBMC preparations.  相似文献   

12.
目的:研究转化生长因子β1(TGF-β1)对小鼠来源树突状细胞(DC)功能的影响。 方法: 在培养体系中同时应用GM-CSF和TGF-β1培养的TGF β-DC,用脂多糖(LPS)观察其对外源刺激的反应,流式细胞仪(FCM)检测细胞表型,应用BrdU ELISA法通过96 h混合淋巴细胞反应(MLR)检测其同种异基因刺激能力,ELISA法测IL-12 p70的分泌水平,分别用半定量RT-PCR法和FCM检测Toll-like受体4(TLR4)表达。 结果: TGF β-DC与常规培养的未成熟DC(imDC)相比,CD80、CD86、I-Ab、CD40表达更低。LPS对TGF β-DC的促成熟作用反应不明显,其表面共刺激分子升高的幅度不大,异基因的刺激能力提高不显著,且IL-12 p70的分泌下降。RT-PCR与FCM都显示TGF β-DC较imDC弱表达TLR4。 结论: TGF β1能抑制DC共刺激分子的表达,TGF β-DC能抵抗LPS的促成熟作用,并可能与其TLR4表达下降有关。  相似文献   

13.
Platelet factor 4 (PF4) is a CXC chemokine secreted by activated platelets. PF4 has been shown to promote monocyte survival and induce the differentiation of monocytes into macrophages. However, the effect of PF4 on differentiation of monocytes into dendritic cells (DC) has yet to be determined. As reported previously, monocytes cultured in RPMI medium containing FCS, granulocyte macrophage colony stimulating factor and IL-4 differentiated into CD1a+ DC. When PF4 was added, the expression of CD1a on DC was inhibited. This inhibitory effect was not observed with the other platelet-derived CXC chemokine, beta-thromboglobulin. The relative number of CD1a- DC increased from 17 to 92% when the PF4 concentration was increased from 0 to 10 micro g/ml. The inhibitory effect of PF4 on CD1a expression was reversed by 50 U/ml heparin. DC developed in the PF4-containing media appeared more adhesive to plastic culture wells and had higher light side scatter by flow cytometry. Immunophenotypically, monocyte-derived DC in the presence of increasing concentrations of PF4 proportionally expressed higher CD86 and lower HLA-DR. The levels of CD11c, CD40 and CD80 remained unchanged with or without PF4. Both CD1a+ DC and CD1a- DC were negative for CD14, CD68 and CD83. Functionally, DC developed in the presence of PF4 had their secretion of tumor necrosis factor-alpha and IL-12 reduced by 75 +/- 10 and 79 +/- 13% respectively when they were stimulated by 100 ng/ml lipopolysaccharide and 50 ng/ml IFN-gamma. CD1a- DC developed in the presence of PF4 were not as active as the control CD1a+ DC in stimulating allogeneic T cells to proliferate. In addition, CD1a- DC were less potent in priming naive CD4+ T cells to secrete both type 1 and 2 cytokines. These results indicate that PF4 can influence differentiation and function of monocyte-derived DC.  相似文献   

14.
目的:探讨T-bet在肝癌患者外周血来源的树突状细胞(dendritic cells,DCs)中表达能否增强其诱导抗肿瘤免疫。方法: 取肝癌患者外周血单核细胞,用5 μg/L rhGM-CSF、5 μg/L rhIL-4培养6 d成不成熟DC(iDC),随后加10 μg/L TNF-α诱导成熟DC。用冻融法制备肝癌细胞株HepG2肿瘤抗原,致敏DC,并分组如下: loaded DC/TNF-α(loaded mDC); loaded DC/TNF-α+IFN-γ(loaded DC/T +I); loaded DC/T-bet (loaded DC/T-bet); iDC。体外刺激淋巴细胞。观察T-bet外源表达对DC的表型、混合淋巴细胞反应、肿瘤特异性细胞杀伤效率影响。结果: 外源表达T-bet促进DC/T-bet表型成熟,促进自体混合淋巴细胞反应,诱导分泌出更多的Th1型细胞因子,增强肝癌细胞特异性杀伤效应。结论: T-bet增强DC抗肿瘤免疫性能。  相似文献   

15.
目的: 探讨巨细胞病毒(CMV)对单核细胞来源的树突状细胞(DC)的感染效率及对受染细胞的功能影响。方法: 以50半数细胞培养感染量(TCID50)滴度的CMV与未成熟及成熟DC(imDC,mDC)共培养,逆转录-聚合酶链反应(RT-PCR)方法检测细胞内CMV即刻早期抗原(IEA)mRNA水平,间接免疫荧光技术检测受染细胞内早期抗原(EA)阳性率,流式细胞仪检测细胞胞内病毒晚期抗原pp65表达,BrdU ELISA法检测受染DCs(cmv-imDC,cmv-mDC)刺激异基因T细胞增殖能力。结果: 感染 12 h,cmv-mDC内IEA mRNA水平低于cmv-imDC,相对表达量分别为0.102±0.020和0.862±0.124(P<0.05)。24 h,imDC组EA阳性率高于mDC组,分别为(62.32±14.20)%和(10.78±3.04)%(P<0.01)。72 h,cmv-DC胞内低表达pp65抗原,imDC和mDC中阳性率分别为4.86%和0.82%。与未处理mDC相比,cmv-imDC经成熟诱导因子LPS作用后,其刺激异基因T细胞增殖能力较弱(均P<0.05);而cmv-mDC,仅当DC/T细胞为 1∶1 时,刺激能力下降(P<0.05)。结论: CMV可有效感染imDC,并在细胞内复制活化;cmv-DC的抗原递呈能力下降。  相似文献   

16.
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   

17.
目的:探讨大鼠deltal基因在树突状细胞(DCs)中的表达及其意义.方法:利用脂质体基因转染技术,将含大鼠deltal基因片段的真核表达载体peDNA3.1(+)/deltal转染入DCs中,采用流式细胞术(FCM)和混合淋巴细胞培养(MLR)等方法检测deltal基因转染对DCs生物学特性的影响.结果:比较实验组、空载体组和对照组DCs在超微结构、细胞周期和细胞生长速度上无明显差异.FCM检测显示,deltal并不影响DCs表面共刺激分子CD80、CD86和MHC-H类分子lad的表达;但deltal基因转染的DCs分泌IL-12的水平明显降低(P<0.05),即使加入LPS刺激后,IL-12的分泌也无明显增加.结论:Deitai/Notch信号表达的增加,不影响DCs的分化与成熟,对其免疫学功能起负性调节作用.Deltal的可能机制为其通过抑制DCs分泌IL-12,来促使Th1/Th2细胞亚群的分化倾向于Th2细胞方向.  相似文献   

18.
Most of the immunosuppressive effects of interleukin-10 (IL-10) are related to functional inhibition of antigen-presenting cells (APC). Herein, we investigate the influence of recombinant (r)IL-10 on human dendritic cells (DC) purified from peripheral blood of healthy volunteers. First, we found that rIL-10 inhibited in a dose-dependent manner the proliferative responses as well as the production of IL-2 and interferon-γ (IFN-γ) in mixed lymphocyte reaction (MLR) between purified T cells and DC. This rIL-10 effect could be attributed to a direct effect on DC, as DC preincubated with rIL-10 were found to be deficient in the induction of alloreactive T cells even when anti-IL-10 neutralizing mAb was added at the time of MLR. Flow cytometric analysis indicated that rIL-10 did not modify the expression of ICAM-1 (CD54) and B7-1 (CD80), but decreased HLA-DR and B7-2 (CD86) expression at the DC surface. We conclude that the inhibitory effect of rIL-10 on primary alloreactive T cell responses involves down-regulation of class II MHC and B7-2 expression at the DC surface.  相似文献   

19.
慢性乙型肝炎患者树突状细胞形态、表型和功能的变化   总被引:2,自引:0,他引:2  
目的 观察慢性乙型肝炎病毒(hepatitis B virus,HBV)感染者树突状细胞(dendritic cells,DC)形态、表型和功能的改变。方法 从13例慢性乙肝患者和11例健康人外周血中分离和培养DC,观察DC的形态。用流式细胞仪检测DC的表面标志,HLA-DR、CD1a,CD80和CD86的表达。用^3H-TdR掺入法,检测DC诱导混合性淋巴细胞反应(mixed leukocytes reaction,MLR)的能力。结果 正常人的DC较慢乙肝患者的DC在形态上更为典型。前者的DC不规则,细胞可表达较多的HLA-DR、CD80和CD86分子(P<0.05),诱导MLR的能力也较强(P<0.05)。结论 慢乙肝患者外周血DC处于不完全成熟状态,其免疫刺激能力较低。  相似文献   

20.
In addition to the effects on T lymphocytes, Cyclosporin A can inhibit dendritic cells allostimulatory capacity, but its precise mechanism remains unknown. The data in this study demonstrated that Cyclosporin A has no effect on the expression of major histocompatibility complex class II and costimulatory molecular CD80, CD86, CD40 on matured DC induced by Lipopolysaccharide in vitro, but can up-regulated B7-DC expression on DC in an Interleukin-4-dependent manner, which is associated with reduced allostimulatory ability of DC. Furthermore, Cyclosporin A treatment inhibited production of Interferon-gammaand TNF-alpha, Interleukin-12p70, but increased production of the Interleukin-10 of DC. Thus, up-regulated expression of B7-DC may be responsible for Cyclosporin A-mediated inhibitory effects on allostimulatory capacity of DC.  相似文献   

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