A study of molecular diagnosis and treatment for chronic cardiac allograft rejection.

本研究分为以下三个部分：1.采用实时定量RT-PCR技术检测了65个不同免疫基因在大鼠心脏移植后发生心脏移植物血管病变(CAV)过程中的动态变化。这种再移植模型提供了更好的研究分子机制的机会，因为慢性排斥反应的发生与所识别基因的表达模式之间的相关性比其他动物模型更严格。总结这部分研究，指出选择性趋化因子/受体系统包括IP10-CXCR3、RANTES-CCR5和MCP1-CCR2的重要性，以及由活化的T细胞产生的细胞因子(干扰素-γ和Fas配体)、血管平滑肌细胞生长因子(PDGF-β、转化生长因子-β)在CAV进展中的意义。2.应用实时荧光定量RT-PCR法研究重症肌无力的临床表现，并提供…进一步证实胸腺瘤细胞上MHC-II类抗原反式激活因子基因表达受抑，参与了胸腺瘤的发病机制。这一结果也表明该方法在包括CAV在内的各种疾病的临床诊断中的可行性。3.利用β-肾上腺素能受体基因和肝细胞生长因子基因进行实验性的基因治疗。在这两种情况下，通过将任何一种基因导入体内的整个心脏，缺血-再灌注损伤都得到了减轻。可以想象，这项技术将为临床治疗CAV提供方法，因为CAV是一种全身免疫抑制下的局部疾病。日本的临床心脏移植才刚刚开始，不可能按原计划将本研究开发的技术应用于慢性排斥的临床诊断。尽管如此，本研究为临床诊断和治疗CAV提供了一些新的方法。较少

This study was performed as three parts described as below.1 : We have measured the dynamics of 65 different immune gene expressions using real-time quantitative RT-PCR in retransplanted rat hearts developing cardiac allograft vasculopathy (CAV). This retransplantation model provided better opportunities to investigate the molecular mechanism, because the correlation between the occurrence of chronic rejection and the expression pattern of the identified gene was more stringent than those in other animal models. In summary of this part of the study, the importance of selective chemokine/receptor systems including IP10-CXCR3, RANTES-CCR5, and MCP1-CCR2 was indicated in addition to the implication of cytokines produced by activated T cells (IFN-γ and Fas ligand), growth factors for vascular smooth muscle cells (PDGF-β, TGF-β) in the progression of CAV.2 : The developed technology using real-time RT-PCR was applied to the investigation of Myasthenia Gravis in clinical situation and provid … More ed the data suggesting the implication of suppressed class II transactivator gene-expression of dysregulation of MHC class II antigen on thymoma cells in pathogenesis of the disease. This results also indicated the feasibility of this method in clinical diagnosis of various diseases includeing CAV.3 : Experimental gene therapy was performed using beta-adrenergic receptor gene and hepatocyte growth factor gene. In both cases, ischemia-reperfusion injury was attenuated by the introduction of either gene into a whole heart in vivo. It is conceivable that the technique should provide the way to treat CAV in clinical situation, because CAV is a local disorder under systemic immunosuppression.Clinical heart transplantation in Japan has just began and it was impossible to apply the technique developed in this study on the clinical diagnosis of chronic rejection as originally planed. Nonetheless, this study provided several new methods applicable to the diagnosis and the treatment of CAV in clinical situation. Less