Oligotherapeutics to enhance CFTR correction

项目摘要 囊性纤维化（CF）是一种致命的肺部疾病，每3500名儿童中就有1名受到影响。F508del CFTR， 最常见的突变存在于90%的CF患者中，已被证明难以治疗。 FDA批准的药物，Orkambi®（lumacaftor和ivacaftor）和Symdeko®（tezacaftor和ivacaftor） ivacaftor），仅改善肺功能2- 4%。改进F508 del CFTR仍然是一个关键 未满足的CF治疗需求。 F508 del CFTR校正的一个障碍是遗传修饰剂的表达增加 TGF-β在CF肺和气道上皮中的表达。TGF-β抑制CFTR功能， Orkambi®和Symdeko®的优势。我们的实验室已经发现microRNA miR-145 介导CFTR校正的TGF-β抑制。TGF-β增加了直接结合至 3 '-非翻译区（3'-UTR）降解CFTR转录物并减少蛋白质 表情CFTR底物的丧失消除了治疗反应。miR-145拮抗作用 克服了这一障碍，提高了Orkambi®的效益。 该项目寻求一种新的方法来增强F508 del治疗。我们将利用一个 反义寡核苷酸（阿索）阻断miR-145与CFTR的结合。我们假设阿索- 定向miR-145靶位点阻断改善F508 del CFTR校正。 具体目标#1：通过反义核酸选择性地增强F508 del CFTR校正 在一些实施方案中，所述寡核苷酸阻断miR-145结合位点。 具体目标#2：测试反义寡核苷酸的体内递送、安全性和功效 人源化CFTR小鼠中的miRNA靶向特异性阻断。 这些目标将提供必要的“下一步”寡治疗的发展。要求1 提供了体外机制、给药和疗效数据，以确定 通过靶向miRNA结合位点的寡核苷酸来改善F508 del CFTR校正。目的2 利用最近开发的全长人源化CFTR小鼠建立递送 可行性、安全性和体内治疗反应。

PROJECT SUMMARY Cystic Fibrosis (CF) is a fatal lung disease that affects 1 in 3500 children. F508del CFTR, the most common mutation present in 90% of CF patients, has proven difficult to treat. The two FDA approved drugs, Orkambi® (lumacaftor and ivacaftor) and Symdeko® (tezacaftor and ivacaftor), only improve lung function by 2-4%. Improving F508del CFTR remains a critical unmet need in CF therapeutics. One barrier to F508del CFTR correction is increased expression of the genetic modifier TGF-β in CF lung and airway epithelia. TGF-β suppresses CFTR function and nullifies the benefit of Orkambi® and Symdeko®. Our laboratory has discovered that the microRNA miR-145 mediates TGF-β inhibition of CFTR correction. TGF-β increases miR-145 which directly binds to the 3'-untranslated region (3'-UTR) to degrade CFTR transcripts and diminish protein expression. Loss of CFTR substrate eliminates therapeutic response. miR-145 antagonism overcomes this barrier to improve Orkambi® benefit. The project pursues a novel approach to augment F508del therapeutics. We will utilize an antisense oligonucleotide (ASO) to block miR-145 binding to CFTR. We hypothesize that ASO- directed miR-145 target site blockade improves F508del CFTR correction. Specific Aim #1: To selectively augment F508del CFTR correction through antisense oligonucleotide blockade of the miR-145 binding site. Specific Aim #2: To test in vivo delivery, safety, and efficacy of antisense oligonucleotide miRNA target specific blockade in humanized CFTR mice. These Aims will provide the necessary “next steps” in oligotherapeutic development. Aim 1 provides the in vitro mechanism, dosing, and efficacy data to establish the rationale for oligonucleotide targeting of the miRNA binding site to improve F508del CFTR correction. Aim 2 utilizes the recently developed full-length humanized CFTR mouse to establish delivery feasibility, safety profile, and therapeutic response in vivo.