mRNA Delivery of a Panel of Single-Domain Antibodies for Combinatorial Deciphering of Therapeutic Targets for Covid-19 Related Cytokine Release Syndrome

项目总结/摘要 严重的COVID-19患者发生急性呼吸窘迫综合征（ARDS）和多器官衰竭， 高炎性细胞因子/趋化因子表达谱。该临床观察结果类似于细胞因子释放 综合征（CRS）是SARS-CoV和MERS-CoV感染患者死亡的主要原因。美国FDA 已经快速跟踪了数十项临床试验，以评估细胞因子阻断疗法在治疗 COVID-19相关CRS。然而，最近从大多数试验中公布的数据表明， 细胞因子或Janus激酶仅在恢复时间方面略微有益于患者，但几乎没有改善死亡率 与标准护理相比。因此，迫切需要一种临床前评价工具， 医学研究人员和制药公司，可以帮助他们确定最有效的组合， 治疗CRS的治疗靶点。我们建议构建单域抗体（sdAb）文库，其包含： 一组抗COVID-1相关的临床表征的、显著升高的细胞因子和趋化因子的sdAb， 19 CRS。该文库可以作为比较和对比不同细胞因子/趋化因子的效力的工具 在人源化PBMC移植的CRS小鼠模型中进行阻断疗法。此外，该库允许测试 同时阻断多种细胞因子/趋化因子作为治疗CRS的组合疗法， 假设是解决问题的方法。为了以迅速的方式实现这一点，文库的模态将是sdAb- 编码mRNA，将其封装在脂质纳米颗粒（LNP）中，以避免蛋白质生产的麻烦， 公式化。OncoTrap还将利用体外抗体筛选和分子进化平台的专业知识， 作为基于脂质纳米颗粒的基因递送系统，其将实现三个具体目标。目标1旨在 筛选针对指定细胞因子或趋化因子的sdAb，其中每一种显示纳摩尔或亚纳摩尔 对目标的亲和力。目的2旨在表征sdAb在药物组合物中递送时的PK特征。 LNP在体内对mRNA的影响。在目标3中，将在移植的人PBMC中测试文库中的两种代表性sdAb。 CRS小鼠模型作为概念研究的证明。NIH-STTR I期研究的成果将为图书馆做好准备， II期的大规模和系统性筛选，其中最有效的治疗CRS的治疗靶点 将被识别。

Project Summary/Abstract Severe COVID-19 patients who develop acute respiratory distress syndrome (ARDS) and multiple organ failures share a hyperinflammatory cytokine/chemokine expression profile. This clinical observation resembles the cytokine release syndrome (CRS) which was the leading cause of mortality in patients infected with SARS-CoV and MERS-CoV. US FDA have fast-tracked dozens of clinical trials to evaluate the efficacy of cytokine blockade therapies in the management of COVID-19 associated CRS. However, recent data released from majority of the trials indicated that blockade of one cytokine or Janus Kinase only marginally benefited patients regarding recovery time, and yet barely improved the mortality rate compared with that of standard care. Therefore, it is urgently needed that a preclinical evaluation tool available to the medical researcher and pharmaceutical companies that could help them identify the most effective combinations of therapeutic targets in the treatment of CRS. We propose to construct a single domain antibody (sdAb) library that contains a panel of sdAbs against clinically-characterized, significantly elevated cytokines and chemokines associated with COVID- 19 CRS. This library could be harnessed as a tool to compare and contrast the potency of different cytokine/chemokine blockade therapy in a humanized PBMC engrafted CRS mouse model. Moreover, the library allows the testing of simultaneous blockade of multiple cytokine/chemokines as a combinatorial therapy for the treatment of CRS which is hypothesized to be resolution to the issue. To accomplish this in a prompt way, the modality of the library will be sdAb- encodings mRNA which is encapsulated in lipid nanoparticle (LNP) to avoid the hassle with the protein production and formulation. OncoTrap will leverage the expertise in in vitro antibody screening and molecular evolution platform, as well as the lipid nanoparticle-based gene delivery system, which will be achieved in three specific aims. Aim 1 is intended to screen the sdAbs against the designated cytokine or chemokine with each of them shows nanomolar or sub-nanomolar binding affinity toward its target. Aim 2 is intend to characterize the PK profiles of sdAbs when they are delivered in the form of mRNA by LNP in vivo. In Aim 3, two representative sdAbs in the library will be tested in human PBMC engrafted CRS mouse model as the proof of concept study. Achievement of NIH-STTR phase I study will prepare the library for large-scale and systemic screening in the phase II, where the most effective therapeutics target(s) in the treatment of CRS will be identified.