Developing a programmable siRNA-based therapeutic platform for gene silencing in the skin

项目总结 皮肤病影响着全球近三分之一的人口。目前的皮肤病药物不足以治疗 这些疾病中有许多，有些很少或根本没有治疗方法。迫切需要开发新的 皮肤科疗法。基于RNA干扰(RNAi)的疗法--例如，小干扰RNA(SiRNA)-- 代表了除小分子和生物制品之外的第三类治疗方式，它们能够使特定的 以及持续的mRNA沉默，以防止导致疾病的蛋白质的产生。随着核科学的最新进展 酸性化学，五种siRNA药物已被FDA批准用于治疗肝脏相关疾病。 SiRNA药物的主要好处包括：(A)易于基于序列的设计；(B)高度特异性；(C)明确的 作用机制；和(D)耐久性(一剂可长达3-6个月)。SiRNA的这些属性允许 快速的药物发现和持久的疾病目标调整以前被认为是“无法用药的”。 这项建议的目的是扩大治疗性siRNAs在皮肤病治疗中的临床应用。 一种沉默免疫介质JAK1(人和鼠)表达并支持功能的siRNA JAK1在体内的抑制作用已被证实。目标1(K99阶段)将系统地评估安全性和 治疗性siRNA选择性沉默JAK1在自身免疫性和炎症性小鼠模型中的作用 皮肤病(即白癜风、皮肤红斑狼疮和皮肤纤维化)。 皮肤中的基因沉默需要高效地将化学工程siRNA输送到表达 目标基因。目标2(K99阶段)将剖析疏水皮肤的生物分布和疗效 局部和系统递送后针对JAK1的结合siRNA。R00阶段将扩大范围 通过测定皮肤细胞的生物分布和新的siRNA结合物和 支架，以及针对干扰素-γ中免疫介质的siRNA(即，IFNGR1JAK2，STAT1和CXCL9/10/11) 和IL15(即IL15和IL15RA)途径，其先导化合物已经被确定。 初步工作已经开发出一种支持同时沉默两个基因的双靶向siRNA支架 在活体内。目标3(K99阶段)将在小鼠模型中测试调节两个炎症靶点的效果 在R00阶段，生物相容的点击化学和纳米结构工程策略 将用于构建可编程的单分子多靶向siRNA支架以增强组合 调节3个或更多的炎症靶点，这是治疗具有复杂病理的皮肤病的关键目标。 该项目将建立一个基于siRNA的平台来调节皮肤中的基因表达，并促进 持续的科学和专业训练。指导K99阶段的研究将在以下条件下进行 一个受人尊敬的指导委员会的指导，其专业知识范围从基础RNA生物学到临床 皮肤科。到R00阶段，PI将准备好建立一个独立的实验室，专注于开发 针对复杂皮肤病的新型siRNA治疗方案。

PROJECT SUMMARY Skin diseases affect nearly one-third of the global population. Current dermatological drugs are inadequate for many of these diseases, and some have few or no treatments available. There is an urgent need to develop new dermatological therapies. RNA interference (RNAi)-based therapeutics—e.g., small interfering RNA (siRNA)— represent a third class of therapeutic modalities, in addition to small molecules and biologics, that enable specific and sustained mRNA silencing to prevent production of proteins driving disease. With recent advances in nucleic acid chemistries, five siRNA drugs have been approved by the FDA for treatment of liver-associated diseases. Key benefits of siRNA drugs include: (a) ease of sequence-based design; (b) high specificity; (c) a well-defined mechanism of action; and (d) long durability (up to 3-6 months from one dose). These properties of siRNAs allow rapid drug discovery and durable modulation of disease targets previously considered “undruggable”. The goal of this proposal is to expand the clinical utility of therapeutic siRNAs for the treatment of skin diseases. An siRNA that silences expression of the immune mediator, JAK1 (human and mouse), and supports functional inhibition of JAK1 in vivo, has been identified. Aim 1 (K99 phase) will systematically evaluate the safety and efficacy of selective JAK1 silencing by therapeutic siRNA in mouse models of autoimmune and inflammatory skin diseases (i.e., vitiligo, cutaneous lupus erythematosus, and skin fibrosis). Gene silencing in skin requires efficient delivery of chemically-engineered siRNA to skin cell types expressing the target gene. Aim 2 (K99 phase) will dissect the skin biodistribution and efficacy profiles of hydrophobically conjugated siRNAs targeting JAK1 following local and systemic delivery. The R00 phase will expand the scope of the siRNA delivery platform by determining skin cell biodistribution and efficacy of new siRNA conjugates and scaffolds, and siRNAs targeting immune mediators in the IFN-γ (i.e., IFNGR1, JAK2, STAT1, and CXCL9/10/11) and IL15 (i.e., IL15 and IL15RA) pathways, for which lead compounds have already been identified. Preliminary work has developed a dual-targeting siRNA scaffold supporting simultaneous silencing of two genes in vivo. Aim 3 (K99 phase) will test the efficacy of modulating two inflammatory targets in the mouse models mentioned in Aim 1. In the R00 phase, biocompatible click chemistry and nanostructure engineering strategies will be used to construct programmable unimolecular multi-targeting siRNA scaffolds to potentiate combinatorial modulation of 3 or more inflammatory targets, a crucial goal for treating skin diseases with complex pathology. This project will establish an siRNA-based platform for modulating gene expression in the skin, and foster the PI’s continued scientific and professional training. Research in the mentored K99 phase will be carried out under the guidance of an esteemed mentor committee, whose expertise range from basic RNA biology to clinical dermatology. By the R00 phase, the PI will be ready to establish an independent lab focused on developing novel siRNA therapeutic programs for complex skin diseases.