Effective induction of immune tolerance by portal venous infusion with IL-10 gene-modified immature dendritic cells leading to prolongation of allograft survival

Dendritic cells (DC) not only initiate T cell responses, but are also involved in the induction of tolerance. The functional properties of DC are strictly dependent on their state of maturation. It has been shown that immature DC can induce immune tolerance and prolong allograft survival. Interleukin-10 (IL-10) is an important immunosuppressive cytokine which inhibits maturation and function of DC. In order to improve the tolerogenicity of DC, we and others showed that adenovirus vectors can effectively mediate IL-10 genetic modification of DC, and IL-10 genetic modification can inhibit MHC II, B7.2, and CD40 expression, IL-12 secretion and the T cell stimulatory capacity of DC. The primary aim of this study is to examine the in vivo effects of this approach on allograft survival in a murine cardiac allograft transplantation model. To our surprise, we observed that infusion of immature DC genetically modified to express IL-10 (DC-IL-10) via the tail vein could not prolong allograft survival in the recipients, but shortened their survival. More interestingly, portal venous infusion of DC-IL-10 markedly prolonged allograft survival. The diverse effects of DC-IL-10 infusion through different routes may be due to the different immune responses to alloantigens in recipients that received DC-IL-10 via either the portal or the tail vein. Decreased cytotoxicity, polarization of Th2 response, poor T cell stimulating activity of liver DC and enhanced incidence of donor DC in the recipients may contribute to the more efficient prolongation of allograft survival observed after portal venous infusion of DC-IL-10. These results suggest that portal venous infusion may be an effective approach for immature DC to induce immune tolerance or hyporesponsiveness against donor antigens, and prolong allograft survival.Abbreviations APC Antigen-presenting cells - CTL Cytotoxic T lymphocytes - DC Dendritic cells - DC-IL-10 IL-10 gene-modified immature dendritic cells - iDC Immature dendritic cells - IL-10 Interleukin-10 - MLR Mixed leukocyte reaction - MOI Multiplicity of infection     

IL-10基因修饰的大鼠树突状细胞表型分析及生物学特性的研究

目的研究IL-10基因修饰后的大鼠树突状细胞(DC)的表型及其生物学特性。方法以含IL-10基因的重组腺病毒载体体外转染大鼠骨髓来源的DC,Western blot测定转染后各组DC中IL-10蛋白的表达,流式细胞仪检测各组DC表面抗原CD83、CD86分子的表达情况,混合淋巴细胞反应法测定各组DC刺激同种异体T细胞增殖的能力。结果 IL-10基因修饰组DC可检测到IL-10高表达,表面抗原CD83、CD86低表达,其刺激T淋巴细胞增殖水平较其他各组低。结论 IL-10基因修饰的DC可有效的表达有功能的IL-10,为研究IL-10修饰的DC诱导同种异体移植免疫耐受奠定了基础。     

IL-4/IL-10诱导的树突状细胞对类风湿性关节炎的作用

目的:探讨经IL-4/IL-10诱导的树突状细胞(DC)对类风湿性关节炎的作用。方法:用Percoll分层离心法从脾脏细胞分离得到DC后,用IL-4或IL-10或IL-4+IL-10进行诱导。用未经诱导和诱导过的DC对类风湿性关节炎大鼠模型进行干扰。SD鼠设为CIA模型组,DC对照组与DC试验组。用ELISA法检测细胞因子与抗体水平,用MTT法检测细胞增殖情况,对鼠爪关节行病理学检测。结果:DC对照组的临床症状评分,病理改变评分,细胞增殖能力,血清中抗胶原抗体及细胞因子水平与CIA模型组的差异无统计学意义。试验组中,注射IL-10-DC能改善CIA鼠的滑膜炎症情况;在初次免疫后第5天注射IL-4-DC能减轻CIA鼠的滑膜炎程度;注射IL-4+IL-10-DC无明显的保护作用。结论:适时注射IL-4或IL-10诱导的DC,对实验性类风湿性关节炎具有保护作用。     

Small interference RNA modulation of IL-10 in human monocyte-derived dendritic cells enhances the Th1 response

RNA interference technology has been used to modulate dendritic cell (DC) function by targeting the expression of genes such as IL-12 and NF-kappa B. In this paper, we demonstrate that transfection of DC with IL-10-specific double strands of small interference RNA (siRNA) resulted in potent suppression of IL-10 gene expression without inducing DC apoptosis or blocking DC maturation. Inhibition of IL-10 by siRNA was accompanied by increased CD40 expression and IL-12 production after maturation, which endowed DC with the ability to significantly enhance allogeneic T cell proliferation. IL-10 siRNA transfection did not affect MHC class II, CD86, CD83, or CD54 expression in mature DC. To further test the ability of IL-10 siRNA-treated DC to induce a T cell response, naive CD4 T cells were stimulated by autologous DC pulsed with KLH. The results indicated that IL-10 siRNA-transfected DC enhanced Th1 responses by increasing IFN-gamma and decreasing IL-4 production. These findings suggest the potential for a novel immunotherapeutic strategy of using IL-10 siRNA-transfected antigen-presenting cells as vaccine delivery agents to boost the Th1 response against pathogens and tumors that are controlled by Th1 immunity.     

IL-10诱导小鼠树突状细胞耐受的分子机制

目的：研究白细胞介素-10 (interleukin-10，IL-10)诱导小鼠来源的树突状细胞(DC)耐受及其与配对免疫球蛋白样受体（PIR-A/B）的关系。方法: 以IL-10（20 μg/L）诱导小鼠来源的树突状细胞系（DC2.4）6 d，即IL-10-DC组，脂多糖（LPS）刺激其48 h为成熟DC2.4细胞（LPS-DC），体外化学合成特异性针对PIR-B的小干扰RNA片段，以脂质体2 000转染IL-10组（Si-DC组）。分别应用半定量RT-PCR和流式细胞仪（FCM）检测DC2.4、IL-10组、LPS组及Si-DC组细胞PIR-A/B的表达。以［3H］-TdR标记法检测上述各组细胞刺激同种异体淋巴细胞的增殖反应(MLR)，ELISA方法测混合培养上清中IFN-γ的水平变化。结果: RT- PCR结果表明，IL-10诱导PIR-B表达升高、PIR-A表达下降，LPS则下调PIR-B、上调PIR-A的表达。FCM检测IL-10组和LPS组的PIR-A/B胞外区PIR表达均升高，且前者明显高于后者。同正常DC2.4和LPS组相比，IL-10可抑制MLR，小干扰RNA沉默PIR-B表达可增强MLR，伴随MLR反应上清中IFN-γ的水平升高。结论: IL-10诱导DC高度表达免疫抑制性受体PIR-B，使其获得耐受，上调PIR-B的表达是IL-10诱导DC耐受的分子机制之一。     

IL-2基因修饰对树突状细胞的生物学特征和功能的影响

目的:观察白细胞介素2(IL-2)基因修饰对树突状细胞(DC)的生物学特征和功能的影响,探讨用IL-2基因修饰DC,增强DC介导特异性抗肿瘤免疫的机制。方法:IL－2基因修饰小鼠骨髓来源的DC后,用扫描电镜观察其表面形态的变化,FACS分析IL-2基因修饰对DC表面免疫分子表达的影响,RT-PCR方法检测DC中 IFN-γ mRNA表达。用3H-TdR掺入法检测IL-2基因修饰后,DC对同种异体T淋巴细胞的刺激作用和对肿瘤抗原的特异性提呈功能。结果:经IL-2基因修饰后,DC表面的伪足增多、变长;其表面与抗原提呈相关的免疫分子Ia、B7-1、B7-2和CD40的表达明显上调;il-2基因修饰的DC(DC-IL-2)中表达IFN-γ mRNA;CD-IL-2不但对同种异体T淋巴细胞有较强的促增殖作用,而且对肿瘤抗原的特异性提呈功能亦明显增强。结论:IL-2基因修饰DC,能促进DC的发育,上调DC表面与抗原提呈相关的免疫分子,增强了DC的生物活性。     

Inhibition of mast cells by interleukin-10 gene transfer contributes to protection against acute myocarditis in rats

Progression of acute myocarditis involves a variety of inflammatory events. Mast cells have been implicated as the source of various cytokines, chemokines and histamine in acute inflammation and fibrosis. Interleukin (IL)-10 has well-known immunomodulatory actions that are exerted during the recovery phase of myocarditis. In this study, 9-week-old male Lewis rats were immunized with cardiac myosin. A plasmid vector expressing mouse IL-10 cDNA (800 mug per rat) was then transferred three times (7, 12 and 17 days after immunization) into the tibialis anterior muscles of the rats by electroporation. Microscopic examination of mast cells was carried out on toluidine blue-stained transverse sections of the mid ventricles. Mouse IL-10 gene transfer significantly reduced mast cell density, cardiac histamine concentration and mast cell growth, and prevented mast cell degranulation. Furthermore, improvement in both myocardial function and the overall condition of the rats was evident from the reduction in the heart weight-to-body weight ratio and inflammatory infiltration as well as improvement in hemodynamic and echocardiographic parameters. These findings suggest that IL-10 gene transfer by electroporation protected against myocarditis via mast cell inhibition.     

Induction of IL-10 producing CD4+ T cells with regulatory activities by stimulation with IL-10 gene-modified bone marrow derived dendritic cells

Dendritic cells (DCs) can induce both tolergenic as well as effective immune responses in the lung. Pulmonary DCs producing interleukin (IL)-10 mediated tolerance induced by respiratory exposure to antigen. IL-10 is an important immunosuppressive cytokine, which inhibits maturation and function of DC. To assess whether IL-10 producing DCs can exert the tolergenic effect through the differentiation of regulatory T cells, bone marrow derived DCs were genetically modified by IL-10 expressing adenovirus. IL-10 gene modified DCs (Ad-IL-10-DC) displayed a characteristic phenotype of immature DCs. Here we showed that in vitro repetitive stimulation of naïve DO11·10 CD4⁺ T cells with Ad-IL-10-DCs resulted in a development of IL-10 producing T-cell regulatory cells. These T cells could not proliferate well but also lost their ability to produce interferon-γ upon restimulation with irradiated splenocytes and ovalbumin peptide. Furthermore, in co-culture experiments these T cells inhibited the antigen-driven proliferation of naïve CD4+ T cells in a dose-dependent manner. Our findings demonstrated that IL-10 producing DCs had the potential to induce the differentiation of Tr1-like cells and suggested their therapeutic use.     

腺病毒载体介导gfp基因在树突细胞的转导及其影响因素的分析

目的：研究腺病毒载体介导外源基因在人树突细胞转染的有效方法。方法：绿色荧光蛋白（gfp）报告基因重组腺病毒的构建采用直接连接法。人树突细胞的制备通过分离人外周血单核细胞，然后在体外经过诱导过程再生。结果：经腺病毒介导实现了gfp基因在树突细胞的转导和表达。病毒滴度对转导效率影响较大，只有使用高滴度（MOI〉100）的重组腺病毒才能获得较高的转导效率（40％以上）；脂质体和多聚赖氨酸可以明显提高转导效率（提高50％左右）。转导效率最高可达65％左右。结论：由腺病毒介导进行树突细胞的转基因需要较高的病毒滴度；脂质体和多聚赖氨酸可以提高基因的转导效率。     

人树突状细胞体外直接抑瘤作用研究

目的：诱导获得人外周血树突状细胞(DCs)，研究其体外直接抑瘤作用及机制。方法：自正常人外周血分离获得单核细胞，体外rhGM-CSF和rhIL-4联合诱导培养，观察细胞形态并检测其相关表型；利用MTT法检测所诱导DCs及其培养上清对不同肿瘤细胞系的体外直接抑瘤效应。结果：诱导5—7天后的悬浮细胞具有典型的DCs形态，流式分析显示HLA-DR表达率为64．02％，CD14表达率为2．34％；抑瘤实验显示：DCs对HT29、Hela及HepG2．2．15三种肿瘤细胞系的生长具有明显抑制，其抑制率分别为20．16％，25．44％，75．41％，而对Lovo和HepG2两种肿瘤细胞系，则无明显的抑制作用。DCs培养上清均未见明显的抑瘤效应。结论：人类DCs可对某些肿瘤细胞的生长产生直接抑制作用，但对不同的肿瘤细胞其作用不同。此作用可能由DCs与肿瘤细胞的直接接触而触发，而与DCs分泌的细胞因子关系不大。     

带有IL-24的腺病毒扩增及其在小鼠树突状细胞中的表达

目的：在293细胞中扩增带有IL-24的腺病毒,感染小鼠树突状细胞,观察IL-24在树突状细胞中的表达。方法：将构建的重组腺病毒表达载体IL-24转染到293细胞中包装、扩增,感染分离培养的小鼠树突状细胞,RT-PCR、Westernblot、荧光显微镜检测IL-24的表达。结果：获得了大量的带有IL-24的腺病毒,成功的感染小鼠树突状细胞,RT-PCR和Westernblot检测结果显示,IL-24在树突状细胞中高表达。结论：带有IL-24的腺病毒可以高效的感染小鼠树突状细胞。     

hIL-10修饰树突状细胞对实验动物淋巴细胞增殖及胞毒效应的影响

目的：探讨hIL-10修饰DC对实验动物免疫功能的影响。方法：将经IL-10基因修饰或未修饰DC腹腔注射C57BL／6致敏小鼠，以致敏或未致敏C57BL／6单个核细胞作为反应细胞，以未修饰DC细胞及修饰DC为刺激细胞。共培养6天，MTT检测细胞增殖，乳酸脱氢酶法测定细胞毒活性。结果：hIL-10对未修饰DC致敏或未致敏小鼠的同种细胞刺激的增殖反应有明显的抑制作用。hIL-10修饰DC诱导不同组小鼠淋巴细胞增殖反应显著低于未修饰DC细胞诱导小鼠淋巴细胞增殖反应，hIL-10修饰DC对不同组小鼠CTL细胞毒活性具有抵抗作用。结论：hIL-10修饰的DC诱导同种小鼠淋巴细胞的增殖反应显著降低和对CTL胞毒活性抵抗。     

IL-10-producing B cells involved in the pathogenesis of Coxsackie virus B3-induced acute viral myocarditis

Background: Interleukin-10 (IL-10)-producing B cells, a subset of regulatory B cells, play critical roles in autoimmune and infectious diseases. However, the role of IL-10-producing B cells in acute viral myocarditis (AVMC) remains unknown. Methods: BALB/c mice were intraperitoneally (i. p.) infected with coxsackievirus B3 (CVB3) to establish AVMC models (AVMC group), while control mice (control group) were treated with phosphate-buffered saline (PBS) i. p. According to the time after injection, the AVMC group mice or control group mice were randomly separated into 1 week and 2 week subgroup. Myocardial histopathological changes were observed by hematoxylin and eosin staining and the frequency of splenic IL-10-producing B cells was measured by flow cytometry. Results: Histopathologic examination of heart tissues showed that mice infected with CVB3 developed AVMC. Compared with control group, the frequency of splenic IL-10-producing B cells was increased significantly in the AVMC group, with the 1 week AVMC subgroup (3.58 ± 0.47%) higher than the 2 week AVMC subgroup (2.50 ± 0.42%) (all P < 0.05). Conclusions: IL-10-producing B cells are increased in CVB3-induced AVMC, indicating that IL-10-producing B cells may play an important role in the pathogenesis of CVB3-induced AVMC.     

IL-18基因修饰增强肿瘤抗原多肽致敏的树突状细胞体内诱导的抗肿瘤免疫反应

目的 :研究肿瘤抗原多肽致敏的白细胞介素 18(IL 18)基因修饰的树突状细胞体内诱导的抗肿瘤免疫反应。方法 :①以Lewis 3LL肺癌细胞特异性抗原肽mut1冲击致敏IL 18基因修饰的骨髓来源的树突状细胞 (DC IL 18 mut1) ,每次用其 1× 10 5 只皮下免疫小鼠 2次 ,然后测定脾细胞的NK活性及CTL杀伤活性 ;②以DC IL 18 mut1每次 2× 10 5 只皮下免疫 1次 ,然后再以 5× 10 53LL细胞攻击 ,在诱导及效应阶段分别以单抗阻断不同免疫成份 ,观察肿瘤的生长。结果 :以DC IL 18 mut1皮下免疫后可诱导出比DC mut1等免疫组更高水平的 3LL肺癌细胞特异性CTL ,并使NK活性明显增加 ;单抗体内阻断实验提示在DC IL 18 mut1免疫诱导阶段 ,CD4 + T细胞和抗原共刺激分子、IFN γ均起到重要作用 ,而效应阶段CD8+ T、IFN γ、NK起作用 ,而CD4 + T则是非必需的。结论 :DC IL 18 mut1皮下免疫后可诱导高水平的抗肿瘤免疫活性 ,其机理与抗原有效提呈、特异性CTL诱导、NK活性增加以及CD4 + 、CD8+ T、NK细胞、IFN γ参与密切相关。     

Involvement of IL-10 in exhaustion of myeloid dendritic cells and rescue by CD40 stimulation

It has recently been shown that immature dendritic cells (DCs) stimulated by a danger signal undergo transient maturation followed by exhaustion. However, the exact mechanism for this has not been elucidated. In this study, we show that interleukin-10 (IL-10) secreted from transiently matured DCs stimulated by danger signals is responsible for this rapid DC exhaustion. Blocking of the autocrine IL-10 enabled transient mature DCs to maintain the mature phenotype for several days. However, these DCs remained phenotypically unstable because the addition of IL-10 altered the transient mature DCs to exhausted DCs. More importantly, stimulation of DCs by CD40 protected transient mature DCs from IL-10-dependent exhaustion, with the result that mature DCs remained stable in the presence of IL-10. Furthermore, in vivo administration of stable mature DCs pulsed with ovalbumin protein induced antigen-specific cytotoxic T lymphocytes (CTLs) effectively, whereas neither exhausted DCs nor transient mature DCs were able to prime a strong antigen-specific CTL response. These results indicate that DC-T cell engagement via CD40-CD154 is required for stable DC maturation leading to effective CTL induction. Otherwise, DCs stimulated solely by a danger signal are temporarily activated, but then rapidly lose their immune-activating capacity under the influence of autocrine IL-10.     

系统性红斑狼疮患者外周血单个核细胞中白细胞介素-10mRNA表达的研究

目的 探讨白细胞介素(IL-10)在系统性红斑狼疮(SLE)中的作用。方法 采用逆转录多聚酶链反应(RT-PCR)及酶联免疫吸附法(ELISA)测定40例SLE患者和20例正常对照组外周血单核细胞(PBMC)IL-10mRNA表达及IL-10自发分泌水平。结果 SLE患者PBMC自发分泌IL-10水平及其IL-10mRNA表达水平均显著高于正常对照组(P<0.01),其中SLE活动期明显高于非活动期(P<0.01),而非活动期又明显高于正常对照组(P<0.01)。结论 IL-10在SLE发病中起重要作用,PBMC分泌IL-10水平对SLE诊断和病情活动性监测有重要临床意义,拮抗SLE患者体内IL-10水平,将为SLE治疗开辟一条新途径。     

Expression profiling of IL-10-regulated genes in human monocytes and peripheral blood mononuclear cells from psoriatic patients during IL-10 therapy

Interleukin-10 (IL-10), originally identified as an inhibitor of pro-inflammatory cytokine production, exerts multiple immunomodulatory functions. Its ability to inhibit a Th1 response has been used in clinical trials for the treatment of inflammatory diseases including psoriasis. However, little is known about the molecular mechanisms of IL-10 functions. We aimed at identifying possible mediators of in vitro IL-10 treatment in monocytes by gene chip technology using Hu95a Affymetrix mRNA arrays with 12,000 genes. To prove relevance of the identified genes for the clinical situation we compared these in vitro results with genes being regulated by IL-10 in peripheral blood mononuclear cells from psoriatic patients undergoing IL-10 therapy. A high proportion of the 1,600 genes up-regulated and 1,300 genes down-regulated in vitro was found to be similarly regulated in vivo. Some genes, which were previously unknown to be regulated by IL-10, can be assigned to known IL-10 functions like e.g. the increase of pathogen clearance. Other new potentially immunomodulating genes have been identified to be regulated by IL-10, but their impact needs to be experimentally evaluated. We could confirm a recently reported up-regulation of heme oxygenase-1 (HO-1). However, we demonstrate that the anti-inflammatory mechanisms of IL-10 remain functional even when HO-1 is irreversibly inhibited.     

Cyclosporin a Up-regulates B7-DC expression on dendritic cells in an IL-4-dependent manner in vitro, which is associated with decreased allostimulatory capacity of dendritic cells

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.