协同刺激分子CD86在母-胎免疫调节中的作用

目的　探讨协同刺激分子CD86在母 胎免疫调节中的作用。方法　建立自然流产模型(CBA×DBA/ 2 )及正常妊娠模型 (CBA×BALB/c)。两种模型分别再分为 3个组 :(1)以大鼠的IgG为对照的对照组 ;(2 )于妊娠第 4、6、8、10天 ,分别给CBA孕鼠腹腔注射大鼠抗小鼠CD86单克隆抗体的多次干预组 ;(3)仅于妊娠第 4天 ,给CBA孕鼠单次腹腔注射抗CD86单克隆抗体的单次干预组。每次腹腔注射的抗体剂量均为 10 0 μg。于妊娠第 14天计算各组胚胎吸收率。 结果　 (1)自然流产模型与正常妊娠模型的对照组胚胎吸收率分别为 2 7 78%和 8 42 %。 (2 )于妊娠第 4、6、8、10天腹腔注射抗CD86单克隆抗体后 ,自然流产模型的多次干预组胚胎吸收率下降至 9 6 8% (P <0 0 5 ) ;而正常妊娠模型的多次干预组胚胎吸收率上升至 13 5 4% (P >0 0 5 )。 (3)妊娠第 4天单次腹腔注射抗CD86单克隆抗体 ,自然流产模型单次干预组的胚胎吸收率下降至 7 14% (P <0 0 0 1) ;而正常妊娠模型单次干预组的胚胎吸收率上升至 11 39% (P >0 0 5 )。结论　妊娠早期 ,尤其在胚胎对母体的致敏阶段 (着床期 ) ,阻断母 胎界面的CD86协同刺激信号 ,将诱导母体对胚胎的免疫耐受 ,从而减少胚胎吸收 ,提高妊娠成功率     

干预CD86协同刺激信号对母胎界面Th1/Th2型细胞因子转录调控及妊娠结局的影响

目的探讨干预CD86协同刺激信号对母胎界面Th1/Th2型细胞因子转录调控及妊娠结局的影响。方法:将正常妊娠模型(CBA/J×BALB/c)和自然流产模型(CBA/J×DBA/2J)CBA孕鼠均分为两组:对照组(各10只)于孕d 4、d 6、d 8腹腔注射大鼠IgG;干预组(各10只)于孕d 4、d 6、d 8腹腔注射大鼠抗小鼠CD86 mAb。孕d 9竞争性半定量RT-PCR测定各组母胎界面组织中Th1型(IL-12、IFN-γ)/Th2型(IL-4、IL-10)细胞因子转录水平;孕d 12比较两种模型各组的胚胎吸收率。结果:正常妊娠模型中,干预CD86协同刺激信号对母胎界面Th1/Th2型细胞因子转录水平及妊娠预后均无显著影响(P>0.05)。自然流产模型中,干预CD86协同刺激信号能够升调节母胎界面局部Th2型而降调节Th1型细胞因子转录水平,并显著改善其妊娠预后(P<0.05)。结论:于孕早期干预CD86协同刺激信号能够调控母胎界面局部Th1/Th2型细胞因子转录,形成维持正常妊娠所需的Th2型免疫偏倚,诱导母胎免疫耐受。     

干预CD86协同刺激信号在诱导母胎界面Th2型免疫偏倚中的作用

目的 :探讨干预CD86协同刺激信号在诱导母胎界面局部形成Th2型免疫偏倚中的作用。方法 :将正常妊娠模型 (CBA×BALB/c)和自然流产模型 (CBA×DBA/ 2 )CBA孕鼠均分为两组 ,于孕第 4、6、8天 ,对照组腹腔注射大鼠IgG ,实验组腹腔注射大鼠抗小鼠CD86mAb ;孕第 9天 ,ELISA测定母胎界面组织培养上清中Th1型 (IFN γ、TNF α) /Th2型(IL 4、IL 10 )细胞因子表达水平 ,并计算IL 4 /IFN γ、IL 10 /IFN γ比值 ;孕第 12天比较两种模型各组的胚胎吸收率。结果 :正常妊娠模型中 ,干预CD86协同刺激信号对母胎界面原有的Th2型免疫偏离及妊娠预后均无显著影响。自然流产模型中 ,干预CD86协同刺激信号能够诱导母胎界面局部形成Th2型免疫偏倚并显著改善其妊娠预后。结论 :于孕早期 ,干预CD86协同刺激信号能够改善母胎界面局部细胞因子微环境 ,形成维持正常妊娠所需的Th2型免疫偏倚 ,诱导母胎免疫耐受     

抗原递呈细胞表面共刺激分子CD80/CD86表达与自然流产的关系

目的 :探讨共刺激分子CD80 /CD86与自然流产的关系。方法 :采用双标记流式细胞分析技术检测自然流产小鼠模型CBA/J×DBA/ 2脾脏及肠系膜淋巴结内 (MLN)抗原递呈细胞MΦ表面CD80 /CD86的表达情况 (n =10 ) ,以正常妊娠小鼠模型CBA/J×BALB /c为对照 (n =5 )。结果 :1、自然流产模型组脾脏内表达CD80MΦ含量为 1.82±0 .4 1% ,与正常妊娠模型组的 1.64%± 0 .61%差异无显著性 (P >0 .0 5 ) ,而表达CD86MΦ含量在自然流产模型组中为 2 .34%± 0 .67% ,明显低于正常妊娠模型组的 5 .98%±2 .4 3% (P <0 .0 5 ) ;2、自然流产模型组MLN内表达CD80MΦ含量为 10 .2 0 %± 5 .4 2 % ,明显高于正常妊娠模型组 1.5 8%± 0 .70 % ,差异有显著性 (P <0 .0 5 ) ,而表达CD86MΦ含量在自然流产模型组中为 1.4 6%± 0 .5 7% ,明显低于正常妊娠模型组 3.96%± 0 .39% (P <0 .0 0 1)。结论 :抗原递呈细胞表面共刺激分子CD80 /CD86的表达异常在自然流产的发病中起重要作用     

淋巴细胞免疫治疗对小鼠自然流产模型母胎界面CD80~+表达及妊娠结局的影响

目的:评价CBA/J×DBA/2小鼠配对组合作为反复自然流产模型的生殖力特点,及其与母胎交界CD80表达间的关系,并研究淋巴细胞免疫治疗(lymphocyte immunotherapy,LIT)对CD80表达水平的影响。方法:对CBA/J×DBA/2小鼠的生殖力特点进行为期120d的观察,并与生殖力正常的4种对照组进行比较。另计算15对CBA/J×DBA/2小鼠孕13d的胚胎吸收率,并用CD80-FITC和CD45-PE双色流式细胞术检测CD80细胞在母胎交界面的构成比。为了明确CD80~+细胞的身份,检测了CD3、DX5(NK细胞)和MHC-Ⅱ在CD80细胞群中的表达水平。此外,检测LIT组与未治疗组CBA/J×DBA/2小鼠胚胎吸收率和CD80细胞的阳性率。结果:CBA/J×DBA/2小鼠的流产特点是为孕10d左右的反复流产。CBA/J×DBA/2小鼠孕13d的胚胎吸收率显著高于BALB/c×DBA/2小鼠(30.8％±16.6％vs.7.7％±6.7％,P相似文献   

阻断协同刺激分子对MMP-9/TIMP-3的表达及妊娠结局的影响

目的：探讨阻断CD86协同刺激分子对自然流产模型孕鼠母胎界面MMP-9和TIMP-3的表达及妊娠结局的影响。方法：实验组于妊娠d 4．5腹腔注射大鼠抗小鼠CD86单抗,对照组注射大鼠同型IgG2b,而正常组不作任何处理。于妊娠d 13．5计算胚胎吸收率,并用免疫组化测定MMP- 9和TIMP-3的表达。结果：实验组的胚胎吸收率和MMP-9均显著低于对照组(P＜0．05),与正常对照组间均无差异；TIMP-3的表达与对照组和正常组比较均无显著差异(P＞0．05)。结论：在妊娠早期阻断CD86协同刺激分子能够通过某些机制诱导自然流产鼠MMP-9/TIMP-3的比值降低并且降低自然流产模型的胚胎吸收率,使模型组的胚胎吸收率恢复至正常妊娠水平。     

IL-4与IL-10联合免疫对趋化因子受体CCR3、CCR5、CXCR3的选择性诱导对自然流产模型小鼠胚胎丢失率的影响

目的:观察IL-4与IL-10对趋化因子受体CCR3、CCR5和CXCR3的选择性诱导对自然流产模型小鼠胚胎丢失率的影响,探讨趋化因子受体CCR3、CCR5、CXCR3在诱导妊娠免疫耐受中的作用。方法:建立自然流产小鼠模型与正常妊娠小鼠模型,观察细胞因子IL-4与IL-10对CCR3、CCR5、CXCR3的选择性诱导作用,用双标记流式细胞分析技术,检测正常妊娠模型组孕鼠(CBA/J×BALB/c)、自然流产模型无干预组孕鼠(CBA/J×DBA/2)、自然流产模型IL-4免疫组孕鼠、自然流产模型IL-4+IL-10联合免疫组孕鼠和自然流产模型-生理盐水(NS)免疫组孕鼠中外周血CD4+T细胞CCR3、CCR5、CXCR3等3类趋化因子受体的表达率,并观察各组孕鼠胚胎丢失率。结果:(1)流产模型无干预组胚胎丢失率显著高于正常妊娠模型组,差异有统计学意义(P<0.01),IL-4免疫组、IL-4+IL-10联合免疫组胚胎丢失率皆明显低于NS组与流产模型无干预组(P<0.01,P<0.01);(2)自然流产模无干预组外周血CD4+T细胞CCR3表达水平明显低于正常妊娠模型组(P<0.01),而CCR5、CXCR3表达率明显高于正常妊娠模型组(P<0.01);转输IL-4、IL-4+IL-10后CCR3表达率明显上调、CXCR3表达率明显下降,均与流产模型无干预组差异有显著性(P<0.01)。此外,IL-4+IL-10联合免疫组外周血CD4+T细胞上CCR5表达率也明显低于流产模型无干预组(P<0.05),但IL-4免疫组与流产模型无干预组无明显差异(P>0.05)。结论:CD4+T细胞上CCR3、CCR5、CXCR3表达异常可能在自然流产发病中起重要作用,细胞因子IL-4与IL-10联合作用可能通过诱导CCR3高表达,抑制CCR5与CXCR3表达来诱导妊娠免疫耐受,降低胚胎丢失率。     

过继转移FasL基因修饰的树突细胞对小鼠自然流产模型胚胎丢失的影响

目的:观察过继转移FasL基因修饰的树突细胞(DC)对小鼠自然流产模型胚胎丢失的影响,探讨它在诱导妊娠免疫耐受中的作用。方法:构建鼠源FasL(mFasL)真核表达载体pcDNA3.1-mFasL,用电转染法将它转染给DBA/2雄鼠骨髓来源的DC,将转染成功的mFasL-DC于交配前经腹腔注射给CBA/J母鼠。实验动物分为6组:(1)正常妊娠模型组(CBA/J×BALB/c);(2)未添加干预的流产模型组(CBA/J×DBA/2);(3)转输DC培养基(DCCM)的流产模型组;(4)转输单纯DC(DC)的流产模型组;(5)转输转染空质粒DC的流产模型组;(6)转输转染mFasL质粒DC的流产模型组,于妊娠第12~14天观察孕鼠胚胎丢失率。结果:转输mFasL-DC后孕鼠胚胎丢失率明显低于未添加干预或转输DC培养基的流产模型组(P<0.01),与转输单纯DC或带空质粒的DC组相比,其胚胎丢失率也明显下降(P<0.05),它与正常妊娠组相比胚胎丢失率无显著差异(P>0.05);转输单纯DC或空质粒的DC组与未添加干预流产模型组相比胚胎丢失率有所下降,但没有统计学差异;转输DC培养基组与未加干预组之间胚胎丢失率无统计学差异(P>0.05)。结论:过继转移mFasL-DC能诱导妊娠免疫耐受,降低小鼠自然流产模型孕鼠胚胎丢失率。     

流产小鼠子宫胎盘组织中TNF-α mRNA及其蛋白的表达

为揭示流产小鼠子宫胎盘组织中TNF-α及其受体(TNFR Ⅰ)的特征性分布表达方式,并探索对流产起预防作用的免疫措施与TNF-α表达水平之间的关系,将CBA/J雌鼠与DBA/2J雄鼠进行杂交致孕,作为自然流产动物模型;取CBA/J及ICR雌鼠,分别与C57BL/6雄鼠交配,致孕前21天于子宫角注射大鼠脾细胞,受孕15或19天后,腹膜内注射环磷酰胺(CP),作为诱发流产的动物模型;收集流     

免疫同种异体脾细胞对小鼠成活新生仔数的影响

Clark等(1980)描述了小鼠自发流产的动物模型,即CBA/J雌鼠与DBA/2J雄鼠交配后,胎鼠吸收率增加。Chaouat等(1983)发现给雌鼠免疫BALB/c雄鼠脾细胞可减少生殖失败率。这种保护作用与抗体的形成有关,此抗体是特异性地针对由主要组织相容性复合体和次要组织相容性位点所控制的抗原。胎鼠吸收率近来已作为重要的指标,用来评价主动和被动免疫的保护作用。根据暴露子宫腔的形态学特点判断妊娠的结局,吸收的胎鼠较活胎显著性减小并常有出血表现,高吸收率发生在孕10～13天。尽管子宫吸收可依据形态学来确定,但     

Blockade of CD80 and CD86 at the time of implantation inhibits maternal rejection to the allogeneic fetus in abortion-prone matings

CD28/CTLA-4 interactions with their specific B7-ligands (CD80 and CD86) play a decisive role in antigenic and allogenic responses. Recently, experimental transplant studies demonstrated that donor-specific tolerance was achieved by blocking these interactions. However, the role of blockade of CD28/B7 costimulatory pathway in the maintenance of materno-fetal tolerance has received little attention. In the present study, abortion-prone CBA/J females mated with DBA/2 males were administered with anti-CD80 and anti-CD86 monoclonal antibodies (mAbs) on day 4 of gestation (time of murine implantation). We demonstrated that the combined use of anti-CD80 and anti-CD86 mAbs induced maternal tolerance to the fetus in the abortion-prone CBA/J mice, and displayed expansion of the maternal CD4(+)CD25+ regulatory T cell population and up-regulated expression of CTLA-4, suggesting an active mechanism of regulatory T cells in suppressing maternal rejection to the fetus. In addition, the anti-CD80/86 mAbs treatment enhanced Th2 and reduced Th1 cytokine production in mice, implying that the development of Th2 cells might contribute to maternal tolerance to her fetus. Together, these findings indicated that blocking CD80 and CD86 enhanced maternal tolerance to her fetus in mice by increasing regulatory T cell function and skewing toward a Th2 response. Our data might provide an enhanced understanding of the maternal-fetal immune relationship and be helpful in clinical trials for immunotherapy of recurrent spontaneous abortion.     

Murine CD45+CD86+ cells isolated from para-aortic lymph nodes in an abortion-prone model

The present study aims to address whether the analysis of CD45+CD86+ cells isolated from para-aortic lymph nodes (pLNs) is valuable in assessment of the status of local immunity at the murine feto-maternal interface. CBA/J x DBA/2 mice, virgin CBA/J mice, and CBA/J x BALB/c mice were used as an abortion-prone model (group A), nonpregnant controls (group N), and fertile controls (group F), respectively. The percentage of CD45+CD86+ cells in the CD45+ cell group (CD45+CD86+ percentage for short) and the absolute number of these cells were determined by means of flow cytometry (FCM), using mononuclear cells isolated from pLNs collected 5.5, 9.5, and 13.5 days post-coitum (dpc), respectively, and mononuclear cells isolated from placentas 13.5 dpc. To clarify the identity of these CD86+ cells, FCM was also performed with CD3, CD19, and DX5 as specific markers for murine T-cells, B-cells, and NK cells, respectively. Both resorption rate and absolute number of resorptions were significantly higher in group A (29.3%, 1.8+/-1.0) than in group F (4.8%, 0.3+/-0.5, P<0.001, respectively). Similarly, both cell percentage and absolute number of CD45+CD86+ cells in pLNs collected 13.5 dpc were significantly higher in group A than in group F (27.5+/-14.0% versus 12.3+/-7.1%, and 1362+/-687 versus 615+/-353, P=0.001, respectively). The CD45+CD86+ percentage was around 7.5% in nonpregnant CBA/J mice, similar to the 10.6% in CBA/JxDBA/2 mice 5.5 dpc, but had increased dramatically, to 23.9%, by 9.5 dpc (P<0.001 versus nonpregnant mice and P=0.002 versus CBA/JxDBA/2 mice 5.5 dpc), and remained at a higher level (27.5%) until 13.5 dpc. However, this trend was not observed in group F during pregnancy. The increased CD45+CD86+ percentage at day 9.5 of gestation, when resorption begins, may support the assumption that CD45+CD86+ cells play a role in the course of embryo resorption. Lymphocyte phenotypic analysis in the lymph nodes that drain the pregnant uterus may be helpful to assess the status of local immunity at the feto-maternal interface.     

Morphometric analysis of the histology of spontaneous fetal resorption in a murine pregnancy

Immunopathology of the spontaneous resorption phenomenon in the CBA x DBA/J murine model was explored using morphometric analysis. Accompanying the previously reported presence of natural killer (NK) cells in resorptive feto-placental units we find major changes in tissue morphology indicating that early infiltration of the feto-placental unit by maternal leukocytes plays a direct role with NK cells in fetal demise. Total number of cell nuclei per field and total nuclear area per field were significantly elevated in feto-placental units containing abnormally increased NK cell presence before detectable resorption as early as day 7 of gestation. This difference persisted throughout all stages of early gestation up to and including the final resorption event at day 10 to 12. Increases in cell density were also detected in areas of the embryonic unit not associated with NK infiltration. These results demonstrate that the spontaneous resorption phenomenon in this model involves: (i) Early (day 7-8) cellular infiltration of the decidual-ectoplacental cone junction associated with the presence in this area of NK cells. (ii) Late (day 8-9) cellular infiltration of the ectoplacental cone.     

CTLA4Ig gene transfer alleviates abortion in mice by expanding CD4+CD25+ regulatory T cells and inducing indoleamine 2,3-dioxygenase

Successful pregnancy requires a state of immunological tolerance since normally the maternal immune system does not reject the semi-allogeneic conceptus. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), a ligand for B7, delivers negative signals to antigen presenting cells (APCs) to compete with CD28 for binding to B7 molecules and down-regulate proinflammatory responses, thus inhibiting T cell activation. Using CBA/J × DBA/2 matings as an abortion-prone model, we observed that adenovirus-mediated CTLA4Ig (Ad-CTLA4Ig) gene transfer improves pregnancy outcome. Ad-CTLA4Ig therapy skewed the ability of serum cytokine production toward a Th2 bias. Flow cytometry revealed that Ad-CTLA4Ig administration expanded peripheral CD4⁺CD25⁺ regulatory T cell populations in CBA/J × DBA/2 matings. Furthermore, Ad-CTLA4Ig administration induced indoleamine 2,3-dioxygenase (IDO) and Foxp3 mRNA expression at the materno-fetal interface. Our results demonstrate that adenovirus-mediated CTLA4Ig gene transfer improves pregnancy outcome in a murine model of abortion by expanding the CD4⁺CD25⁺ regulatory T cell population and inducing IDO mRNA expression.