在基本层面上，信使RNA（mRNA）基因治疗涉及将体外转录的（IVT）mRNA传递到目标细胞的细胞质中，在那里被翻译成所需的蛋白质。IVT mRNA相比于基于DNA和重组蛋白质的方法具有多种优势，使其成为广泛的治疗应用的理想选择。IVT mRNA在细胞转染后在细胞质中翻译，可以编码几乎任何目标蛋白质。值得注意的是，它不会进入细胞核，从而避免了其整合到基因组中和插入突变的风险。IVT mRNA的大规模生产比重组蛋白质的生产更少复杂，符合Good Manufacturing Practice的mRNA生产易于扩展，理想地为非现场以及更个性化的治疗方法做好准备。通过利用各种优化的序列元素，化学修饰，纯化技术和传递方法，可以优化IVT mRNA的安全性，药代动力学和药效学，包括其固有的免疫刺激能力，以适用于不同的治疗应用。在COVID-19大流行期间，IVT mRNA的价值最近得到证明，因为基于mRNA的疫苗的有效性超过了已建立的技术，并且数百万剂迅速部署。在本篇综述中，我们将讨论IVT mRNA的化学修饰，并强调许多临床前和临床应用，包括癌症和传染病疫苗，癌症免疫治疗，蛋白质替代，基因编辑和细胞重编程。版权所有©2022 Elsevier Inc.

At the fundamental level, messenger RNA (mRNA)-based therapeutics involves the delivery of in vitro-transcribed (IVT) mRNA into the cytoplasm of a target cell, where it is translated into the desired protein. IVT mRNA presents various advantages compared to DNA and recombinant protein-based approaches that make it ideal for a broad range of therapeutic applications. IVT mRNA, which is translated in the cytoplasm after transfection into cells, can encode virtually any target protein. Notably, it does not enter the nucleus, which avoids its integration into the genome and the risk of insertional mutagenesis. The large-scale production of IVT mRNA is less complex than production of recombinant proteins, and Good Manufacturing Practice-compliant mRNA production is easily scalable, ideally poising mRNA for not only off-the-shelf, but more personalized treatment approaches. IVT mRNA's safety profile, pharmacokinetics, and pharmacodynamics, including its inherent immunostimulatory capacity, can be optimized for different therapeutic applications by harnessing a wide array of optimized sequence elements, chemical modifications, purification techniques, and delivery methods. The value of IVT mRNA was recently proved during the COVID-19 pandemic when mRNA-based vaccines outperformed the efficacy of established technologies, and millions of doses were rapidly deployed. In this review, we will discuss chemical modifications of IVT mRNA and highlight numerous preclinical and clinical applications including vaccines for cancer and infectious diseases, cancer immunotherapy, protein replacement, gene editing, and cell reprogramming.Copyright © 2022 Elsevier Inc. All rights reserved.