Department of Biomedical Engineering, Yale University, New Haven, CT, 06511, USA.
Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, 06511, USA.
Biomaterials. 2018 Sep;176:122-130. doi: 10.1016/j.biomaterials.2018.05.043. Epub 2018 May 25.
Gene delivery is known to be a complicated multi-step biological process. It has been observed that subtle differences in the structure and properties of polymeric materials used for gene delivery can lead to dramatic differences in transfection efficiency. Therefore, screening of properties is pivotal to optimizing the polymer. So far, most polymeric materials are built in a "bottom-up" manner, i.e. synthesized from monomers that allow modification of polymer composition or structural factors. With this method, we previously synthesized and screened a library of biodegradable poly(amine-co-ester) (PACE) terpolymers for optimized DNA delivery. However, it can be tedious and time consuming to synthesize a polymer library for screening, particularly when small changes of a factor need to be tested, when multiple factors are involved, and when the effects of different factors are synergistic. In the present work, we evaluate the potential of PACE to deliver mRNA. After observing that mRNA transfection efficiency was highly dependent on both end group composition and molecular weight (MW) of PACE in a synergistic manner, we developed a "top-down" process we called actuation, to simultaneously vary these two factors. Some of the actuated PACE (aPACE) materials presented superior mRNA delivery properties compared to regular PACE, with up to a 10-fold-increase in mRNA transfection efficiency in vitro. Moreover, when aPACE was used to deliver mRNA coding for erythropoietin (EPO) in vivo, it produced high levels of EPO in the blood for up to 48 h without inducing systemic toxicity. This polymer constitutes a new delivery vehicle for mRNA-based treatments that provides safe yet potent protein production.
基因传递被认为是一个复杂的多步骤的生物过程。人们已经观察到，用于基因传递的聚合物材料的结构和性质的细微差异可能导致转染效率的显著差异。因此，筛选性能对于优化聚合物至关重要。到目前为止，大多数聚合物材料都是以“自下而上”的方式构建的，即从允许修饰聚合物组成或结构因素的单体合成。通过这种方法，我们之前合成并筛选了一系列可生物降解的聚（胺-酯）（PACE）三聚物文库，以优化 DNA 传递。然而，为了筛选而合成聚合物文库可能既繁琐又耗时，尤其是当需要测试一个因素的微小变化时，当涉及多个因素时，以及当不同因素的影响具有协同作用时。在本工作中，我们评估了 PACE 传递 mRNA 的潜力。在观察到 mRNA 转染效率高度依赖于 PACE 的端基组成和分子量（MW）以协同方式后，我们开发了一种我们称之为“自上而下”的方法，即同时改变这两个因素。一些经过驱动的 PACE（aPACE）材料与常规 PACE 相比表现出更好的 mRNA 传递性能，在体外的 mRNA 转染效率提高了 10 倍。此外，当 aPACE 被用于体内传递编码促红细胞生成素（EPO）的 mRNA 时，它在血液中产生了长达 48 小时的高 EPO 水平，而没有引起全身毒性。这种聚合物构成了一种新的用于基于 mRNA 的治疗的递药载体，提供了安全而有效的蛋白质生产。
