内皮源性吲哚胺2,3-双加氧酶抑制周细胞迁移及收缩蛋白表达

 目的: 探讨内皮源性吲哚胺2,3-双加氧酶(IDO)对周细胞迁移及收缩蛋白表达的影响。方法: 体外培养人肺动脉内皮细胞(HPAECs)及大鼠脑微血管周细胞。建立过表达IDO的HPAECs模型(IDO-HPAECs)。实验分为3组:对照组,以HPAECs条件培养基干预周细胞;处理组,以IDO-HPAECs条件培养基干预周细胞;抑制组,以含1-甲基色氨酸(1-mT)的IDO-HPAECs条件培养基干预周细胞。测定共培养体系一氧化氮(NO)、色氨酸及犬尿氨酸浓度。观察周细胞活性、迁移及收缩蛋白表达情况。结果: IDO-HPAECs条件培养基干预周细胞6～48 h对其活性无显著影响。处理组的周细胞迁移能力显著低于对照组(P < 0.01),抑制组显著高于处理组(P < 0.01)。共培养体系的NO浓度在各组间差异无统计学意义(P > 0.05)。处理组的色氨酸浓度显著低于对照组(P < 0.01),而抑制组显著高于处理组(P < 0.01)。处理组的犬尿氨酸浓度显著高于对照组(P < 0.01),而抑制组显著低于处理组(P < 0.01)。处理组的α-平滑肌肌动蛋白与结蛋白表达水平显著低于对照组(P < 0.01),抑制组显著高于处理组(P < 0.01)。结论: 内皮源性IDO抑制周细胞迁移及收缩蛋白表达,可能参与机体微血管功能调控。     

吲哚胺2,3-双加氧酶与树突状细胞

吲哚胺2,3-双加氧酶(IDO)是降解必需氨基酸色氨酸的限速酶,广泛表达于各种组织和细胞,在感染或炎症期间其表达量明显增高.而树突状细胞(DC)是专职的抗原提呈细胞,IDO在其内的表达可影响DC的表型和功能,进而抑制T细胞的免疫反应.研究IDO和DC的关系对深入理解IDO在免疫系统中的作用以及开发新的免疫调节策略都具有重要意义.     

吲哚胺2,3-双加氧酶1在胃癌中的研究进展

胃癌 (Gastric Cancer,GC) 是全球第五大最常见的恶性肿瘤,也是第四大癌症死亡相关原因。胃癌异质性明显,肿瘤微环境复杂,免疫检查点抑制剂虽然在晚期胃癌中展现出一定抗肿瘤疗效,但获益人群仍在少数。吲哚胺2,3-双加氧酶 1 (Indoleamine 2,3-Dioxygenase 1,IDO1) 是色氨酸沿犬尿氨酸途径代谢中的关键酶,对肿瘤免疫逃逸起到了关键作用。目前已有多项研究表明IDO1在胃癌发生发展及幽门螺杆菌感染和EB病毒感染中发挥重要作用,所以靶向IDO1有望成为胃癌免疫治疗的新策略。本文就IDO1作用机制、IDO1在胃癌及相关疾病中的研究进展及IDO1抑制剂在胃癌中的应用前景进行综述。     

Vav1在吲哚胺2,3双加氧酶抑制T细胞中的作用初探

目的:探讨吲哚胺2,3双加氧酶(IDO)抑制T细胞中信号传导分子Vav1的分子机制.方法:应用稳定表达IDO的CHO细胞株,与纯化的外周血T细胞共孵育,检测IDO抑制T细胞增殖,诱导凋亡的情况,通过semi-quantitative RT-PCR检测T细胞中Vav1、IL-2 mRNA表达变化;Western blot及免疫沉淀技术检测Vav1蛋白表达及活化情况.结果:IDO可抑制T细胞的增殖.T细胞中Vav1和IL-2 mRNA水平明显下降(P<0.05).而且,IDO还能使Vav1蛋白的表达和磷酸化水平降低.结论:研究证实在肿瘤局部产生于抗原呈递细胞或肿瘤细胞的IDO,可能通过抑制细胞内重要的信号传导蛋白Vav1的表达和磷酸化过程,使肿瘤浸润淋巴细胞的主动免疫受损,有利于肿瘤发生免疫逃逸.     

吲哚胺2,3双加氧酶(IDO)的免疫调节作用

吲哚胺 2 ,3双加氧酶 (indoleamine 2 ,3 dioxygenase ,IDO )是肝脏以外唯一可催化色氨酸沿犬尿酸途径分解代谢的限速酶 ,在哺乳动物的组织与细胞 ,尤其是淋巴组织和胎盘中广泛表达。它通过降解局部组织中的色氨酸 ,在诱发宿主免疫防御、抑制T细胞免疫和抗肿瘤免疫、诱导母胎免疫耐受和移植物免疫耐受中均发挥重要的代谢性免疫调节作用。     

补肾中药对蜕膜巨噬细胞吲哚胺2,3-二氧化酶的影响

目的：探讨补肾中药对人早孕蜕膜巨噬细胞吲哚胺2，3-二氧化酶(Indoleanline 2，3-dioxygenase，IDO)的影响。方法：半定量RT-PCR测蜕膜IDO mRNA表达；Western blot检测蜕膜巨噬细胞IDO蛋白质表达；ELISA测蜕膜巨噬细胞和淋巴细胞共培养上清液中IL-10、IFN-γ含量，高效液相色谱法测上清色氨酸、犬尿氨酸含量，以二者比值表示IDO活性。结果：正常组蜕膜IDOmRNA表达高于难免流产组；IDO抑制剂使Th细胞因子平衡偏离TL2型；中药血清可提高IDO蛋白质表达及活性，恢复Th细胞因子平衡。结论：蜕膜巨噬细胞IDO正常表达和活性是维持妊娠所必需，补肾中药可提高IDO活性至正常水平。     

吲哚胺2,3二加氧酶与自身免疫性疾病

自身免疫性疾病的发病机制主要在于机体自身耐受的破坏，机体产生自身抗体和（或）自身反应性淋巴细胞，导致疾病的发生。最近很多研究表明，吲哚胺2，3-二加氧酶（indoleamine 2，3-dioxygenase，IDO）催化的色氨酸代谢与自身免疫耐受机制有关，表达IDO的细胞能够抑制T细胞免疫应答，在自身免疫性疾病的发病机制中起重要作用。因而研究IDO介导色氨酸代谢途径可以为阐明自身免疫疾病的发病机制和治疗自身免疫性疾病提供一种全新的观念。     

瘤源性IDO2对黑色素瘤形成及生长的影响

目的研究B16-BL6细胞内IDO2基因表达对小鼠黑色素瘤生长、发展及抗肿瘤免疫的影响。方法通过G418药物筛选建立稳定细胞系B16-BL6/IDO2^+及B16-BL6/IDO2^+,q PCR法检测IDO2的表达,MTT实验检测IDO2表达对细胞增殖的影响;然后以构建的稳定细胞在小鼠体内建立肿瘤模型,观察IDO2表达对黑色素瘤形成、生长的影响;最后在处死小鼠后通过流式细胞术检测引流淋巴结内Treg、CD4^+/CD8^+T细胞百分比及T淋巴细胞凋亡率,LDH法检测肿瘤特异性细胞毒反应来观察肿瘤组织内IDO2表达对引流淋巴结内肿瘤免疫的影响。结果成功建立B16-BL6/IDO2^+及B16-BL6/IDO2^-稳定细胞系:B16-BL6/IDO2^-细胞持续稳定低表达IDO2且不受LPS及IFN-γ的诱导;与B16-BL6/IDO2^+细胞相比,B16-BL6/IDO2^-细胞在体外增殖速度减慢,体内实验显示其肿瘤生长速度减慢、肿瘤质量减轻;进一步流式细胞术结果发现:引流淋巴结内Treg百分比下降、CD8^+T细胞数量增加、T淋巴细胞的凋亡率减少;LDH法检测CD8^+细胞特异性特异性杀伤肿瘤细胞反应增强。结论黑色素瘤细胞内IDO2的表达参与体内肿瘤的生长过程,且能影响其引流淋巴结内肿瘤免疫反应。     

早孕绒毛及蜕膜组织中酪氨酸磷酸酶-1 / 2( SHP-1,SHP-2) 与吲哚胺2,3-双加氧酶( IDO) 的表达及其相关性

目的:研究母胎界面中吲哚胺2,3-双加氧酶(IDO)及酪氨酸磷酸酶-1/2(SHP-1,SHP-2)的表达及其相关性,以探索母胎免疫耐受的新机制。方法:30 例正常早孕6 ~8 周妇女行人工流产获取绒毛及蜕膜组织,用Western blot 方法检测绒毛、蜕膜组织中的酪氨酸磷酸酶-1/2(SHP-1、SHP-2)与IDO 的蛋白表达,分析IDO 与SHP-1、SHP-2 的相关性。结果:人早孕绒毛及蜕膜组织中均有SHP-1、SHP-2 的表达,与IDO 的表达呈正相关;SHP-1、SHP-2 和IDO 在蜕膜组织中的表达均高于绒毛;结论:在正常生理妊娠状态下,母胎界面中SHP-1、SHP-2可能参与调节IDO 的表达,在维持母胎界面的免疫耐受状态起着重要作用。     

SOCS3和吲哚胺2,3-双加氧酶(IDO)在早孕绒毛和蜕膜组织中的表达呈负相关

目的探讨人早孕时细胞因子信号传送阻抑物3(SOCS3)及吲哚胺2,3-双加氧酶(IDO)在母胎界面的表达及其相关性。方法用Western blot法检测正常妊娠绒毛、蜕膜组织中SOCS3及IDO的表达。结果正常妊娠绒毛及蜕膜组织中均有IDO及SOCS3蛋白的表达,SOCS3与IDO表达呈高度负相关。SOCS3在绒毛和蜕膜组织中的表达无差异,而IDO在蜕膜组织中表达较高。结论在正常生理妊娠状态下,母胎界面中SOCS3参与调节IDO的表达,在妊娠免疫耐受的调节中起重要作用。     

Ambivalent effects of dendritic cells displaying prostaglandin E2-induced indoleamine 2,3-dioxygenase

Prostaglandin E2 (PGE(2)), an abundantly produced lipid messenger in mammalian organisms, has been attributed to possess potent albeit ambivalent immunological functions. Recently, PGE(2) has been reported to stimulate the commonly believed immunosuppressive indoleamine 2,3-dioxygenase (IDO) pathway in human dendritic cells (DCs), but without promoting DC immunosuppressive activity. Here, we report that PGE(2) used as a DC maturation agent apparently has more diverse functions. PGE(2)-matured DCs acquired powerful IDO activity, which was sustained even after removing PGE(2). These IDO-competent DCs were able to stimulate allogeneic T-cell proliferation, but achieved inhibitory activity as their content in DC/T-cell co-cultures increased. The DC inhibitory activity was reversed upon blockade of IDO activity, confirming that the suppressive effect was in fact mediated by IDO and occurred in a dose-dependent fashion. IDO-mediated T-cell suppression was restored upon re-stimulation of T cells in the absence of IDO activity, confirming its reversibility. T cells stimulated by PGE(2)-matured IDO-competent DCs were sensitized to produce multiple cytokines, comprising Th1, Th2, and Th17 phenotypes. Collectively, these data suggest that T cells stimulated by PGE(2)-matured DCs are not terminally differentiated and their ultimate type of response may be formed by microenvironmental conditions.     

Expression and function analysis of indoleamine 2 and 3-dioxygenase in bladder urothelial carcinoma

Indoleamine 2, 3-dioxygenase (IDO) is a rate-limiting enzyme for tryptophan metabolism inducing immune tolerance of tumors. The purpose of this study is to investigate IDO expression and its prognostic significance in bladder urothelial carcinoma (BUC). In this study, immunohistochemical staining for IDO expression in BUC tissues (n = 84) and normal bladder tissues (n = 22) was performed. The mRNA expression levels of IDO in BUC and normal bladder were analyzed by quantitative RT-PCR. Survival analysis was performed for the correlation of IDO expression and clinicopathological factors with disease-free survival. Positive expression of IDO was found in 48 of 84 cases in BUC tissues and was significantly correlated with histological classification, histological grade and TNM stage. While IDO expression in normal bladder tissues was expressed in only 4 of 22 (18.2%) cases. Moreover, IDO mRNA levels of BUC were significantly higher than that of normal bladder. We also found that IDO, histological grade and TNM stage were closely associated with DFS. These results indicated that IDO was related to the progression of BUC and might be one of the crucial prognostic factors for BUC.     

人外周血单个核细胞和肿瘤细胞中吲哚胺2,3双加氧酶mRNA水平的实时定量RT-PCR分析

目的 定量分析HIV-1感染者及高危人群外周血单个核细胞(PBMC)和人源肿瘤细胞在Toll样受体(TLR)配体刺激前后吲哚胺2,3双加氧酶(indoleamine 2,3-dioxygenase,IDO)的表达水平.方法 建立人IDO mRNA的TaqMan探针实时荧光定量RT-PCR检测方法;检测HIV-1阳性个体和高危人群PBMC中IDO mRNA水平;检测TLR4、TLR7/8、TLR9配体刺激前后人黏膜(T84、Caco2、Hela)和白细胞(THP-1、MT-4)来源肿瘤细胞中IDO mRNA的水平.结果 HIV-1阳性个体PBMC中IDO mRNA水平较高危人群高(103.42拷贝IDO mRNA/106拷贝GAPDH mRNA);但也有部分高危人群个体的PBMC含有较高水平的IDO mRNA;肿瘤细胞在TLR配体刺激后IDO mRNA的水平可以显著升高,因细胞系和TLR配体种类不同而异.结论 本研究表明IDO可能在我国HIV-1感染者体内病毒免疫逃逸和肿瘤发生中起作用,值得深入研究.     

Quercetin inhibits the invasion and mobility of murine melanoma B16-BL6 cells through inducing apoptosis via decreasing Bcl-2 expression

Quercetin has been known to have anti-tumor and anti-oxidation activities. In the present study, we have investigated its in vitro anti-metastatic activity. Quercetin inhibited the invasion and mobility of murine melanoma B16-BL6 cells in a dose-dependent manner but did not affect their adhesion to either laminin, fibronectin, or type VI collagen. Moreover, quercetin significantly inhibited the proliferation of B16-BL6 cells only in the case of time incubation longer than 48 h. Quercetin dose-dependently decreased the cell rates in S and G2–M phases of cell cycle. The effect of quercetin to cause a remarkable apoptosis of B16-BL6 cells was also demonstrated by flow cytometric assay as well as DNA fragmentation with a typical 180-bp ladder band in agarose electrophoresis and a quantitative analysis. Furthermore, quercetin markedly inhibited the expression of anti-apoptotic protein Bcl-2 but hardly influenced Bcl-X_L. These results suggest that the inhibition of quercetin on invasiveness and migration of B16-BL6 cells are closely associated with the arrest of cell cycle as well as the induction of apoptosis by decreasing the Bcl-2 expression. This revised version was published online in July 2006 with corrections to the Cover Date.     

IDO/TTS色氨酸代谢途径对类风湿关节炎滑膜T细胞增殖的影响

自身反应性T细胞在类风湿关节炎(RA)疾病的发生发展中发挥着极其重要的作用,抑制这群细胞是RA治疗的关键.表达吲哚胺2,3-双加氧酶(indoleamine 2,3-dioxygenase,IDO)的树突状细胞(DC)能够通过此代谢通路剥夺环境中的色氨酸,并生成促凋亡因子犬尿氨酸等,使T细胞的增殖和功能受抑制,最终诱导...