The Role of Telomeres in Lung Transplant Recipient Immunity and Outcomes

项目摘要 肺移植(LTX)是终末期肺部疾病和特发性肺疾病患者的唯一治疗选择 肺纤维化(IPF)是北美最常见的适应症。然而，IPF肺移植接受者 与所有其他肺部疾病相比，IPF-LTRS的移植存活率更差。基因突变 负责端粒维护是最近IPF和我们组最常见的可识别原因 结果显示，肺移植对端粒介导性疾病患者的疗效提高了四分之一。 有一种可识别的罕见变异的患者。端粒维持基因缺陷的患者有 一系列免疫异常，使他们容易受到病毒感染。尽管有一个虚弱的 免疫系统，据报道，这些患者排斥供体肺的比率与个人相似或更快。 没有端粒介导的疾病。造成这一现象的机制尚不清楚。基于 我们的初步数据假设，肺移植揭示了一种复杂的综合症，它影响了病毒 宿主防御、免疫抑制耐受和同种异体移植排斥反应。此外，我们假设损害了 然而，通过增强免疫衰老，巨细胞病毒感染加剧了获得性免疫 同种异体免疫和其他免疫机制可以抵消和促进移植后的肺排斥反应 端粒较短的受者。我们将我们的方法分为三个相关和协同的目标。在目标1中， 我们检查了端粒中介性疾病患者的原发CMV感染的后果，并测试了是否 端粒功能障碍和巨细胞病毒感染这两个因素相互作用，共同推动免疫衰老。在目标2中，我们探索 免疫系统减弱的个体发生肺排斥反应的机制。最后， 在目标3中，我们测试我们来自匹兹堡大学的最新发现是否可以在多个 来自肺移植结果组的中心组患者，并检查肺移植后保持结果 根据基因发现和端粒长度进行分层的移植。我们期望这些研究将会有所帮助。 改善端粒介导疾病患者的护理和预后。

Project Summary Lung transplantation (LTx) is the only therapeutic option for patients with end-stage lung disease and idiopathic pulmonary fibrosis (IPF) is the most common indication in North America. However, IPF lung transplant recipients (IPF-LTRs) have worse transplant survival compared to all other lung diseases. Mutations in the genes responsible for telomere maintenance are the most common identifiable cause of IPF and our group recently showed that lung transplantation enriches for patients with telomere-mediated disease with as many as a quarter of patients having an identifiable rare variant. Patients with defects in telomere-maintenance genes have an array of immunologic abnormalities that render them susceptible to viral infections. Despite having a weakened immune system, these patients have been reported to reject donor lungs at similar or faster rates than individuals without telomere-mediated disease. The mechanism responsible for this phenomenon are unknown. Based on our preliminary data, we hypothesize that lung transplantation unmasks a complex syndrome that impacts viral host defense, immunosuppression tolerance and allograft rejection. Further, we hypothesize that impaired adaptive immunity is exacerbated by Cytomegalovirus infection by augmenting immunosenescence, however alloimmune and other immune mechanisms can offset and facilitate lung rejection outcomes in transplant recipients with short telomeres. We have divided our approach into three related and synergistic aims. In Aim 1, we examine the consequences of primary CMV infection in patients with telomere-mediate disease and test if two hits, telomere dysfunction and CMV infection, cooperate to drive immune senescence. In Aim 2, we explore the mechanisms that are responsible for lung rejection in individuals with weakened immune systems. Finally, in Aim 3, we test if our recent findings from the University of Pittsburgh can be replicated and extended in a multi- center group of patients from the Lung Transplant Outcomes Group and examine keep outcomes following lung transplantation when stratified by genetic findings and telomere length. We expect that these studies will help improve care and outcomes in patients with telomere-mediated disease.