Leveraging single index cell RNA sequencing to study macrophage populations in frozen biopsies of dermatomyositis

项目总结/摘要 皮肌炎（DM）是一种获得性自身免疫性肌肉疾病，其病因尚不清楚。DM 没有特定的FDA批准的治疗方法，也没有在其他疾病中使用免疫抑制药物的标签外使用 自身免疫性疾病已被证明是无效或不可行的。高达20%的患者在5年内死于疾病 3年，类似于第三阶段乳腺癌。这项拨款提案的目标是了解 免疫系统的某些部分参与了糖尿病的发生，并发现哪些特征可以预测糖尿病的病程。 每一个病人。 我们的长期目标是更好地了解DM是如何开始的，确定免疫系统的哪些部分， 系统参与，预测每个患者的病程，并找到新的治疗方法，以改善患者的 结果。这项资助的目的是确定巨噬细胞-一种特定的免疫细胞类型-是否参与了 DM的肌肉炎症。我们的中心假设是，巨噬细胞招募其他免疫细胞进入巨噬细胞。 糖尿病患者的肌肉，导致疾病。我们的理由是，通过确定特定类型的 通过研究参与炎症的巨噬细胞，我们将能够更好地了解主要的免疫途径 参与DM。这将为未来的治疗确定新的目标，以改善患者的预后。我们 具体目标将测试以下假设：（目的1）识别正常人中的巨噬细胞群体， 骨骼肌和皮肌炎;（目的2）阐明糖尿病严重程度的巨噬细胞特征。 在这个项目结束后，我们将第一次有能力分离免疫细胞， 冷冻的病人活检标本这一进展是必要的，因为目前的单细胞分析依赖于新鲜活检 样品，由于DM的稀有性而无法获得。利用这个，我们将了解主要的巨噬细胞 类型参与糖尿病，并找出具体的肌肉活检功能（S）影响临床病程。 这一贡献是重要的，因为它将第一次不仅打开许多冷冻组织， 研究目的，但也将提供参与炎症的所有巨噬细胞的广泛概述， 确定治疗的特定新靶点。拟议的研究是创新的，因为我们将使用最先进的 免疫学和遗传技术，以前仅限于使用新鲜组织，以实现这些目标。在 此外，我们将确认一组用于免疫荧光显微镜的商业抗体， 与更严重的DM疾病相关的特定巨噬细胞。这种方法将是临床上适用的， 对目前的治疗方法有很大的影响。

PROJECT SUMMARY/ABSTRACT Dermatomyositis (DM) is an acquired autoimmune muscle disorder with poorly understood causes. DM has no specific FDA-approved treatments and off-label use of immunosuppressive medications used in other autoimmune conditions has proven ineffective or infeasible. Up to 20% of patients die of their disease within 5 years, similar to stage III breast cancer. The goals of this grant proposal are to gain an understanding of which parts of the immune system are involved in causing DM and find which features predict the course of disease in each patient. Our long-term goals are to better understand how DM begins, identify which parts of the immune system are involved, predict the course of disease in each patient, and find new treatments to improve patient outcomes. The objective of this grant is to identify if macrophages – a specific immune cell type - participate in muscle inflammation in DM. Our central hypothesis is that macrophages recruit other immune cells into the muscles of patients with DM, causing disease. Our rationale is that by identifying the specific type of macrophages involved in inflammation, we will be able to better understand the main immune pathways involved in DM. This will identify new targets for future therapies that will improve patient outcomes. Our specific aims will test the following hypotheses: (Aim 1) Identify macrophage populations in normal skeletal muscle and dermatomyositis; (Aim 2) Elucidate macrophage signatures of DM severity. Upon conclusion of this project we will, for the first time, have the ability to isolate immune cells from frozen patient biopsies. This advance is necessary as current single cell analyses depend on fresh biopsy samples, which are not available due to the rarity of DM. Using this, we will understand the main macrophage types involved in DM and find out which specific muscle biopsy feature(s) influence clinical disease course. This contribution is significant because it will, for the first time, not only open up many frozen tissues for research purposes, but will also provide a broad overview of all macrophages participating in inflammation, identifying specific new targets for therapy. The proposed research is innovative as we will use cutting edge immunology and genetic technologies, previously limited to the use of fresh tissues, to achieve these goals. In addition, we will confirm a panel of commercial antibodies to use in immunofluorescent microscopy to identify specific macrophages associated with worse DM disease. This method will be clinically applicable and may have a large impact on current approaches to treatment.