Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, Ludwig-Maximilian University of Munich, Butenandtstr. 5-13, 81377 Munich, Germany.
Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, Ludwig-Maximilian University of Munich, Butenandtstr. 5-13, 81377 Munich, Germany.
J Pharm Sci. 2020 Jan;109(1):62-67. doi: 10.1016/j.xphs.2019.10.003. Epub 2019 Oct 4.
Clustered regularly interspaced short palindromic repeats (CRISPR) form the adaptive immune system in archaea and bacteria and have been modified for genome engineering in eukaryotic cells. CRISPR systems contain 2 components, a single-guide RNA, which is a short RNA composed of a 20 nucleotide sequence that targets specific sites in the genomic DNA and a scaffold necessary for its binding to the CRISPR-associated endonuclease (Cas9). Because of its high efficiency and accuracy, the CRISPR-Cas9 genome editing based therapies are poised to treat a multitude of human diseases with a promise to target previously "undruggable" proteins. As the first in-body clinical trial with CRISPR-Cas9 is embarked on, the risks associated with administering the genome editing machinery to patients become increasingly relevant. Recent studies have demonstrated an innate and adaptive cellular immune response to Cas9 in mouse models and the presence of anti-Cas9 antibodies and T-cells in human plasma. Pre-existing immunity against therapeutic Cas9 delivery could decrease its efficacy in vivo and may pose significant safety issues. This review focuses on the immunogenicity of the Cas9 protein and summarizes potential approaches to circumvent the problem of immune recognition.
成簇规律间隔短回文重复序列（CRISPR）构成了古细菌和细菌的适应性免疫系统，并已被修改用于真核细胞的基因组工程。CRISPR 系统包含 2 个组件，一个是单指导 RNA（sgRNA），它是由靶向基因组 DNA 中特定位点的 20 个核苷酸序列组成的短 RNA，以及一个支架，用于其与 CRISPR 相关内切酶（Cas9）结合。由于其高效性和准确性，基于 CRISPR-Cas9 的基因组编辑治疗方法有望治疗多种人类疾病，并有望靶向以前“不可成药”的蛋白质。随着第一个基于 CRISPR-Cas9 的体内临床试验的开展，将基因组编辑机制施用于患者的相关风险变得越来越重要。最近的研究表明，在小鼠模型中存在针对 Cas9 的固有和适应性细胞免疫反应，以及人血浆中存在抗 Cas9 抗体和 T 细胞。针对治疗性 Cas9 递送的预先存在的免疫可能会降低其在体内的疗效，并可能带来重大的安全问题。本综述重点介绍了 Cas9 蛋白的免疫原性，并总结了规避免疫识别问题的潜在方法。
