1 Department of Microbiology and Immunology.
2 Lee Patterson Allen Transplant Immunobiology Laboratory, Division of Transplant, Department of Surgery.
Am J Respir Cell Mol Biol. 2019 Jun;60(6):678-686. doi: 10.1165/rcmb.2018-0224OC.
Chronic obstructive pulmonary disease-associated chronic inflammation has been shown to lead to an autoimmune phenotype characterized in part by the presence of lung autoreactive antibodies. We hypothesized that ischemia-reperfusion injury (IRI) liberates epitopes that would facilitate preexisting autoantibody binding, thereby exacerbating lung injury after transplant. We induced emphysema in C57BL/6 mice through 6 months of cigarette smoke (CS) exposure. Mice with CS exposure had significantly elevated serum autoantibodies compared with non-smoke-exposed age-matched (NS) mice. To determine the impact of a full preexisting autoantibody repertoire on IRI, we transplanted BALB/c donor lungs into NS or CS recipients and analyzed grafts 48 hours after transplant. CS recipients had significantly increased lung injury and immune cell infiltration after transplant. Immunofluorescence staining revealed increased IgM, IgG, and C3d deposition in CS recipients. To exclude confounding alloreactivity and confirm the role of preexisting autoantibodies in IRI, syngeneic Rag1 (recombination-activating protein 1-knockout) transplants were performed in which recipients were reconstituted with pooled serum from CS or NS mice. Serum from CS-exposed mice significantly increased IRI compared with control mice, with trends in antibody and C3d deposition similar to those seen in allografts. These data demonstrate that pretransplant CS exposure is associated with increased IgM/IgG autoantibodies, which, upon transplant, bind to the donor lung, activate complement, and exacerbate post-transplant IRI.
慢性阻塞性肺疾病相关的慢性炎症已被证明会导致自身免疫表型,其部分特征是存在肺部自身反应性抗体。我们假设缺血再灌注损伤(IRI)会释放表位,从而促进预先存在的自身抗体结合,从而加重移植后的肺损伤。我们通过 6 个月的香烟烟雾(CS)暴露在 C57BL/6 小鼠中诱导肺气肿。与未吸烟的同龄(NS)小鼠相比,CS 暴露的小鼠血清中自身抗体明显升高。为了确定预先存在的完整自身抗体库对 IRI 的影响,我们将 BALB/c 供体肺移植到 NS 或 CS 受体中,并在移植后 48 小时分析移植物。CS 受体在移植后肺损伤和免疫细胞浸润明显增加。免疫荧光染色显示 CS 受体中 IgM、IgG 和 C3d 沉积增加。为了排除混杂的同种异体反应性并确认预先存在的自身抗体在 IRI 中的作用,我们进行了同基因 Rag1(重组激活蛋白 1 敲除)移植,其中受体用来自 CS 或 NS 小鼠的混合血清重建。CS 暴露小鼠的血清明显增加了 IRI,与对照小鼠相比,抗体和 C3d 沉积的趋势与同种异体移植相似。这些数据表明,移植前 CS 暴露与 IgM/IgG 自身抗体增加有关,这些抗体在移植后与供体肺结合,激活补体,加重移植后 IRI。