Anti-eosinophil Gene Therapy for Eosinophilic Esophagitis

抽象的。嗜酸性食管炎(EoE)是一种慢性上消化道功能障碍，影响 儿童和成人的特点是食管炎性嗜酸性粒细胞，进行性紊乱 食道结构、食道功能障碍、吞咽困难和食物嵌塞。没有审批通过的 EoE的治疗；标准护理包括局部或全身糖皮质激素和饮食调整。 LEXEO治疗公司是一家早期基因治疗公司，正在开发一种单一给药基因 非人灵长类血清型r.10型腺相关病毒Lxi02治疗EoE的实验研究 静脉注射的载体，旨在通过基因修饰肝脏来表达和分泌 针对嗜酸性粒细胞的单抗，导致嗜酸性粒细胞从循环中清除 还有纸巾。基因治疗相对于传统的单抗治疗的优势是持久稳定的。 单次静脉注射后抗Eos单抗水平的变化。与The Crystal合作 Weill Cornell实验室建立了一种新的小鼠EoE模型，该模型通过对花生的致敏而诱导， 导致食道嗜酸性粒细胞聚集并伴随食道排列紊乱 建筑。单次静脉注射编码抗Siglec-F的AAVr.10manti-Eos，a 抗小鼠嗜酸性粒细胞唾液酸结合免疫球蛋白样凝集素的单抗 (Siglec-F)，诱导小鼠嗜酸性粒细胞凋亡，清除血液中高嗜酸性粒细胞，减少 食道结构紊乱中嗜酸性粒细胞聚集减少 食物嵌塞。作为将这种疗法移植到人类的下一步，我们产生了LXI02 (AAVRh.10hAnti-Eos)，与AAVRh.10mAnti-Eos相同，但与anti-Siglec-8的编码序列相同，以及 小鼠Siglec-F的人IgG1同源物这个第一阶段STTR的重点是证明LXI02 是一种有效的抗人嗜酸性粒细胞疗法。我们将静脉注射LX02至 不同剂量的免疫缺陷小鼠，并随着时间的推移评估肝脏表达和血液中抗- Siglec-8和表达的抗Siglec-8将：与Siglec-8和人嗜酸性粒细胞结合；介导 人嗜酸性粒细胞的自然杀伤细胞抗体依赖的细胞毒性和凋亡；增强清除 人嗜酸性粒细胞在免疫缺陷小鼠中的表达；并证明Lxi02基因的表达可以被关闭 如果需要，请关闭。随着第一阶段STTR的成功，LEXEO将申请第二阶段STTR，目标是 将LXI02翻译成人类治疗EoE的方法。目的1.证明Lxi02将在 免疫缺陷小鼠持续、稳定水平的抗Siglec-8有效地降低了 人类嗜酸性粒细胞的水平。目的2.证明GalNAc结合的siRNA同源化合物的给药 Lxi02中的一个序列将抑制Lxi02编码的抗Siglec8抗体的表达。

Abstract. Eosinophilic esophagitis (EoE), a chronic upper gastrointestinal disabling disorder affecting children and adults, is characterized by eosinophil esophageal inflammation, progressive disordering of esophageal architecture, esophageal dysfunction, dysphagia and food impaction. There are no approved therapies for EoE; standard of care includes topical or systemic glucocorticoids and diet modification. LEXEO Therapeutics, an early stage gene therapy company, is developing a single administration gene therapy to treat EoE with LXi02, a nonhuman primate serotype rh.10 adeno-associated virus (AAVrh.10) vector administered intravenously, designed to genetically modify the liver to express and secrete a monoclonal antibody directed against eosinophils, resulting in clearance of eosinophils from the circulation and tissues. The advantage of gene therapy over conventional monoclonal therapy is persistent stable levels of the anti-Eos monoclonal following single intravenous therapy. In collaboration with the Crystal laboratory, Weill Cornell, a novel murine EoE model was created, induced by sensitization to peanuts, resulting in esophageal eosinophil accumulation and concomitant derangement of esophageal architecture. A single intravenous administration of AAVrh.10mAnti-Eos coding for anti-Siglec-F, a monoclonal antibody directed against murine eosinophil sialic acid-binding immunoglobulin-like lectin (Siglec-F), induced murine eosinophil apoptosis, clearance of blood hyper eosinophilia, reduction in esophageal eosinophil accumulation reduction in esophageal architectural derangement and decrease in food impaction. As the next step in translating this therapy to humans, we generated LXi02 (AAVrh.10hAnti-Eos), identical to AAVrh.10mAnti-Eos, but with the coding sequence for anti-Siglec-8, an IgG1 human ortholog of murine Siglec-F. The focus of this phase I STTR, is to demonstrate that LXi02 is effective as an anti-human eosinophil therapy. We will administer LXi02 intravenously to immunodeficient mice at varying doses and assess over time liver expression and blood levels of anti- Siglec-8 and that the expressed anti-Siglec-8 will: bind to Siglec-8 and to human eosinophils; mediate natural killer cell antibody-dependent cytotoxicity and apoptosis of human eosinophils; enhance clearance of human eosinophils in immunodeficient mice; and demonstrate that LXi02 gene expression can be shut off if required. With success of this phase I STTR, LEXEO will apply for a phase 2 STTR, with the goal to translate LXi02 to human therapy for EoE. Aim 1. To demonstrate that LXi02 will mediate in immunodeficient mice persistent, steady state levels of anti-Siglec-8 that functions effectively to reduce levels of human eosinophils. Aim 2. To show that administration of GalNAc conjugated siRNA cognate to a sequence in LXi02 will suppress expression of the anti-Siglec8 antibody coded by LXi02.