Autoantibody-induced type 1 interferons and RBC alloimmunization in sickle cell disease

项目摘要 镰状细胞病（SCD）患者的RBC同种异体免疫可导致潜在的致命性溶血事件。 与所有其他疾病相比，SCD患者的RBC同种异体免疫发生率最高 包括输血负担相似的人群。解释这种高发病率的因素很难 明白识别这些因素将允许识别可能受益于以下因素的SCD患者： 个性化输血方案和稀有抗原匹配单位输血者的炎症 已显示促进RBC同种抗体反应。我们以前报道过，促炎性1型 病毒感染或自身免疫诱导干扰素（IFNα/β）促进红细胞同种异体免疫 输血模型最近的研究，包括本申请中包含的初步数据，表明， 许多患有SCD的患者具有IFNα/β基因特征，其通过IFNα/β刺激的白细胞表达来定义。 基因.然而，导致IFNα/β活化的机制，包括信号传导途径、受体和配体， 我们对此知之甚少。几乎所有IFNα/β诱导受体都是核酸的细胞内受体。因此，在本发明中， 含核酸细胞的吞噬作用，包括在SCD中升高的网织红细胞，具有潜在的 以激活IFNα/β通路。抗RBC自身抗体促进红细胞吞噬作用， 具有这种自身抗体的发生率增加的SCD患者。而RBC同种抗体/RBC 自身抗体的相关性尚不清楚，我们的初步数据表明，网织红细胞计数与自身抗体相关， IFNα/β基因评分和自身抗体调理的网织红细胞的红细胞吞噬作用， SCD诱导人巨噬细胞中的IFNα/β活化。初步数据还显示，抗红细胞自身抗体 在临床前输血模型中诱导IFNα/β活化和RBC同种免疫。 在这个建议中，我们的目的是测试假设，红细胞自身抗体促进IFNα/β介导的红细胞 通过鉴定诱导IFNα/β（Aim 1）的炎症途径并确定 自身抗体诱导的IFNα/β炎症对SCD小鼠RBC同种免疫的影响（目的2）。在目标1中， 将在人巨噬细胞的共培养物中鉴定由自身抗体诱导的IFNα/β途径， 来自患有和不患有SCD的患者的网织红细胞，并且将在临床前小鼠中测试结果的扩展 模型已鉴定的途径和受体将为SCD中诱导IFNα/β的配体提供信息。目标2代表 在SCD临床前模型中首次研究IFNα/β调节的RBC同种异体免疫， 揭示可能导致RBC同种异体免疫发生率升高的机制。 该项目的长期目标包括提高对SCD中促炎性干扰素的理解， 靶向IFNα/β调节治疗可能是有益的。调查结果也可能具有适用性 除了SCD之外，炎症干扰素在自身免疫和其他疾病过程中起着关键作用。

Project Summary RBC alloimmunization in patients with sickle cell disease (SCD) can lead to potentially fatal hemolytic events. Patients with SCD have the highest incidence of RBC alloimmunization, compared to all other disease populations including those with similar transfusion burdens. Factors explaining this high incidence are poorly understood. Identifying such factors would allow for identification of patients with SCD who may benefit from personalized transfusion protocols and rare antigen-matched units. Inflammation in the transfusion recipient has been shown to promote RBC alloantibody responses. We previously reported that proinflammatory type 1 interferons (IFNα/β) induced by viral infection or autoimmunity promote RBC alloimmunization in pre-clinical transfusion models. Recent studies, including preliminary data included in this application, have revealed that many patients with SCD have an IFNα/β gene signature, defined by leukocyte expression of IFNα/β stimulated genes. However, mechanisms leading to IFNα/β activation, including signaling pathways, receptors, and ligands, are poorly understood. Nearly all IFNα/β-inducing receptors are intracellular receptors for nucleic acids. Thus, phagocytosis of nucleic acid containing cells, including reticulocytes which are elevated in SCD, has the potential to activate IFNα/β pathways. Anti-RBC autoantibodies facilitate erythrophagocytosis, with alloimmunized patients with SCD having an increased incidence of such autoantibodies. While the RBC alloantibody/RBC autoantibody association is poorly understood, our preliminary data indicate that reticulocyte counts correlate with IFNα/β gene scores and erythrophagocytosis of autoantibody-opsonized reticulocytes from patients with SCD induces IFNα/β activation in human macrophages. Preliminary data also show that anti-RBC autoantibodies induce IFNα/β activation and RBC alloimmunization in a pre-clinical transfusion model. In this proposal, we aim to test the hypothesis that RBC autoantibodies promote IFNα/β-mediated RBC alloimmunization in SCD by identifying inflammatory pathways that induce IFNα/β (Aim 1) and determining the effects of autoantibody-induced IFNα/β inflammation on RBC alloimmunization in SCD mice (Aim 2). In Aim 1, IFNα/β pathways induced by autoantibodies will be identified in co-cultures of human macrophages and reticulocytes from patients with and without SCD, and the extension of findings will be tested in pre-clinical murine models. Identified pathways and receptors will inform ligands that induce IFNα/β in SCD. Aim 2 represents the first investigation of IFNα/β-regulated RBC alloimmunization in pre-clinical models of SCD and has the potential to reveal a mechanism that may contribute to the elevated incidence of RBC alloimmunization. Long term goals of this project include improved understanding of proinflammatory interferons in SCD, with the possibility that targeted IFNα/β-modulated therapy may be beneficial. Findings may also have applicability beyond SCD, with inflammatory interferons playing a critical role in autoimmunity and other disease processes.