Background OX40/OX40 ligand （OX40/OX40L） and programmed death-1/programmed death ligand-1 （PD-1/PD-L1） co- stimulator/signals play important roles in T cell-induced immune responses. The aim of this study was to i...Background OX40/OX40 ligand （OX40/OX40L） and programmed death-1/programmed death ligand-1 （PD-1/PD-L1） co- stimulator/signals play important roles in T cell-induced immune responses. The aim of this study was to investigate the roles of OX40/OX40L and PD-1/PD-L1 costimulatory pathways in mouse islet allograft rejection. Methods Lentiviral vectors containing OX40L siRNA sequences and an adenovirus vector containing the PD-L1 gene were constructed. The streptozotocin-induced model of diabetes was established in C57BL/6 （H-2b） mice. Diabetic C57BL/6 mice were randomly allocated into five groups： group 1, untreated control; group 2, Ad-EGFP treatment; group 3, Ad-PD-L1 treatment; group 4, OX40L-RNAi-LV treatment; group 5, OX40L-RNAi-LV combined with Ad-PD-L1 treatment. Lentiviral vector and the adenovirus vector were injected, singly or combined, into the caudal vein one day before islet transplantation. The islets of DBA/2 （H-2d） mice were transplanted into the renal subcapsular space of the diabetic recipients. Recipient blood glucose and the survival time of the allografts were monitored. Antigen-specific mixed lymphocyte reaction was also evaluated.展开更多
目的探讨在输注供者低表达CD40的树突状细胞（dendriticcells，DC）后，调节性T细胞（regulatory T cell，Treg）对小鼠移植心脏的保护作用。方法以针对小鼠CD40基因的RNA干扰（RNAinterference，RNAi）慢病毒载体在体外感染供者骨髓来...目的探讨在输注供者低表达CD40的树突状细胞（dendriticcells，DC）后，调节性T细胞（regulatory T cell，Treg）对小鼠移植心脏的保护作用。方法以针对小鼠CD40基因的RNA干扰（RNAinterference，RNAi）慢病毒载体在体外感染供者骨髓来源的DC，制备低表达CD40的耐受性DC（T01-DC）。建立小鼠异位腹腔心脏移植模型。设置异系对照组、未感染DC组及单纯慢病毒感染DC组。观察各组移植心脏存活时间，评定术后7d移植物排斥反应、病理分级，并以流式细胞术检测手术前后外周血CD4^＋CD25^＋Treg变化水平。结果CD40-RNAi慢病毒载体在体外感染DC48h后，CIM0mRNA表达明显受到抑制，抑制效率为80．9％。CD40表达明显下降，由74．37％±4．08％降至40．07％±4．03％（P〈0．05）。与异系对照组和未感染DC组相比，单纯慢病毒感染DC组移植心脏存活时间（14±4）d明显延长（P〈0．01）；术后7d急性排斥反应病理分级均明显降低（P〈0．05）；术后3d．7d外周血CD4^＋CD25^＋Treg水平均明显升高（P〈0．05）。结论CD4^＋CD25^＋Treg对输注供者低表达CD40的树突状细胞的小鼠移植心脏具有保护作用。展开更多
The activation of T cells to differentiate and to proliferate is an essential step in the immune response to antigen, especially in cell mediated acute allograft rejection. Besides the int...The activation of T cells to differentiate and to proliferate is an essential step in the immune response to antigen, especially in cell mediated acute allograft rejection. Besides the interaction of CD3/TCR complex with Ag/MHC complex presented on antigen presenting cells, a complete T cell activation and proliferation requires a second costimulatory signal. The interaction of CD28/CTLA 4 and B7 is a major costimulatory pathway for T Cell activation. Inhibition of this pathway results in development of antigen specific unresponsiveness and clonal anergy.In present study,the biologic function of anti CD28 monoclonal antibody and its Fab fragment were investigated in vitro and in vivo.The results indicate that mAbCD28 and its Fab fragments could promote the functional recovery of allografts and prolong the graft survival,but could not reverse the acute rejection or induce transplantation tolerance in the rat PTG allograft model. We also found that peripheral TNF α level and NK cell activity were suppressed in the presence of mAbCD28 and its Fab fragments for a relatively long time after PTG transplantation.展开更多
Background This study was to evaluate whether anergic cells induced by the blockade of CD40-CD154 and CD28-B7 costimulatory pathways can act as potent immunoregulatory cells in vitro and prolong cardiac allograft...Background This study was to evaluate whether anergic cells induced by the blockade of CD40-CD154 and CD28-B7 costimulatory pathways can act as potent immunoregulatory cells in vitro and prolong cardiac allograft survival after adoptive transfer KH*2/5DMethods Anergic cells were induced in vitro by the addition of anti-CD154 and anti-CD80 monoclonal antibodies (mAbs) to primary MLR (mixed lymphocyte reaction) consisting of BALB/c as responder and C3H as stimulator Anergic cells were added to a newly formed MLR in assessing the regulatory capacity and antigen specificity of anergic cells The ability of anergic cells to respond to antigen and/or exogenous recombinant mouse interleukin-2 (rmIL-2) was tested For in vivo studies, anergic cells were intravenously injected into 3 0-Gy γ-irradiated BALB/c mice immediately after heterotopic abdominal cardiac transplantation To prolong allograft survival, recipient mice injected with anergic cells received rapamycin therapy (1 mg·day -1 ·kg -1 ) KH*2/5DResults Anergic cells strongly suppressed the proliferation of naǐve BALB/c splenocytes against the original (C3H) stimulator in a dose-dependent manner, but they failed to suppress the proliferation of naǐve BALB/c splenocytes against the third-party (C57BL/6J) stimulator The anergic state was reversed by both original (C3H) stimulator and additional exogenous IL-2 In in vivo studies, untreated irradiated BALB/c mice rejected C3H cardiac allografts with a mean survival time of (8 6±1 1) days, whereas those injected with the anergic cells rejected the allografts with a mean survival time of (11 8±1 9) days, which was slightly longer than that of the untreated mice The protocol based on anergic cells injection plus rapamycin therapy could prolong allograft survival significantly [(29 6±4 4) days] Conclusions Anergic cells induced by the blockade of CD40-CD154 and CD28-B7 costimulatory pathways can act as potent immunoregulatory cells in vitro , and prolong ca展开更多
文摘Background OX40/OX40 ligand （OX40/OX40L） and programmed death-1/programmed death ligand-1 （PD-1/PD-L1） co- stimulator/signals play important roles in T cell-induced immune responses. The aim of this study was to investigate the roles of OX40/OX40L and PD-1/PD-L1 costimulatory pathways in mouse islet allograft rejection. Methods Lentiviral vectors containing OX40L siRNA sequences and an adenovirus vector containing the PD-L1 gene were constructed. The streptozotocin-induced model of diabetes was established in C57BL/6 （H-2b） mice. Diabetic C57BL/6 mice were randomly allocated into five groups： group 1, untreated control; group 2, Ad-EGFP treatment; group 3, Ad-PD-L1 treatment; group 4, OX40L-RNAi-LV treatment; group 5, OX40L-RNAi-LV combined with Ad-PD-L1 treatment. Lentiviral vector and the adenovirus vector were injected, singly or combined, into the caudal vein one day before islet transplantation. The islets of DBA/2 （H-2d） mice were transplanted into the renal subcapsular space of the diabetic recipients. Recipient blood glucose and the survival time of the allografts were monitored. Antigen-specific mixed lymphocyte reaction was also evaluated.
文摘目的探讨在输注供者低表达CD40的树突状细胞（dendriticcells，DC）后，调节性T细胞（regulatory T cell，Treg）对小鼠移植心脏的保护作用。方法以针对小鼠CD40基因的RNA干扰（RNAinterference，RNAi）慢病毒载体在体外感染供者骨髓来源的DC，制备低表达CD40的耐受性DC（T01-DC）。建立小鼠异位腹腔心脏移植模型。设置异系对照组、未感染DC组及单纯慢病毒感染DC组。观察各组移植心脏存活时间，评定术后7d移植物排斥反应、病理分级，并以流式细胞术检测手术前后外周血CD4^＋CD25^＋Treg变化水平。结果CD40-RNAi慢病毒载体在体外感染DC48h后，CIM0mRNA表达明显受到抑制，抑制效率为80．9％。CD40表达明显下降，由74．37％±4．08％降至40．07％±4．03％（P〈0．05）。与异系对照组和未感染DC组相比，单纯慢病毒感染DC组移植心脏存活时间（14±4）d明显延长（P〈0．01）；术后7d急性排斥反应病理分级均明显降低（P〈0．05）；术后3d．7d外周血CD4^＋CD25^＋Treg水平均明显升高（P〈0．05）。结论CD4^＋CD25^＋Treg对输注供者低表达CD40的树突状细胞的小鼠移植心脏具有保护作用。
文摘The activation of T cells to differentiate and to proliferate is an essential step in the immune response to antigen, especially in cell mediated acute allograft rejection. Besides the interaction of CD3/TCR complex with Ag/MHC complex presented on antigen presenting cells, a complete T cell activation and proliferation requires a second costimulatory signal. The interaction of CD28/CTLA 4 and B7 is a major costimulatory pathway for T Cell activation. Inhibition of this pathway results in development of antigen specific unresponsiveness and clonal anergy.In present study,the biologic function of anti CD28 monoclonal antibody and its Fab fragment were investigated in vitro and in vivo.The results indicate that mAbCD28 and its Fab fragments could promote the functional recovery of allografts and prolong the graft survival,but could not reverse the acute rejection or induce transplantation tolerance in the rat PTG allograft model. We also found that peripheral TNF α level and NK cell activity were suppressed in the presence of mAbCD28 and its Fab fragments for a relatively long time after PTG transplantation.
文摘Background This study was to evaluate whether anergic cells induced by the blockade of CD40-CD154 and CD28-B7 costimulatory pathways can act as potent immunoregulatory cells in vitro and prolong cardiac allograft survival after adoptive transfer KH*2/5DMethods Anergic cells were induced in vitro by the addition of anti-CD154 and anti-CD80 monoclonal antibodies (mAbs) to primary MLR (mixed lymphocyte reaction) consisting of BALB/c as responder and C3H as stimulator Anergic cells were added to a newly formed MLR in assessing the regulatory capacity and antigen specificity of anergic cells The ability of anergic cells to respond to antigen and/or exogenous recombinant mouse interleukin-2 (rmIL-2) was tested For in vivo studies, anergic cells were intravenously injected into 3 0-Gy γ-irradiated BALB/c mice immediately after heterotopic abdominal cardiac transplantation To prolong allograft survival, recipient mice injected with anergic cells received rapamycin therapy (1 mg·day -1 ·kg -1 ) KH*2/5DResults Anergic cells strongly suppressed the proliferation of naǐve BALB/c splenocytes against the original (C3H) stimulator in a dose-dependent manner, but they failed to suppress the proliferation of naǐve BALB/c splenocytes against the third-party (C57BL/6J) stimulator The anergic state was reversed by both original (C3H) stimulator and additional exogenous IL-2 In in vivo studies, untreated irradiated BALB/c mice rejected C3H cardiac allografts with a mean survival time of (8 6±1 1) days, whereas those injected with the anergic cells rejected the allografts with a mean survival time of (11 8±1 9) days, which was slightly longer than that of the untreated mice The protocol based on anergic cells injection plus rapamycin therapy could prolong allograft survival significantly [(29 6±4 4) days] Conclusions Anergic cells induced by the blockade of CD40-CD154 and CD28-B7 costimulatory pathways can act as potent immunoregulatory cells in vitro , and prolong ca
