Development of delivery strategies for CRISPR‐Cas9 genome editing

Abstract The clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR‐related protein 9 (Cas9) genome editing system has attracted much attention due to its powerful genome editing capacity. However, CRISPR‐Cas9 components are easily degraded by acids, enzymes, and other substances in the body fluids after entering the organism, thus efficiently delivering the CRISPR‐Cas9 system into targeted organs or cells has been a central theme for promoting the application of CRISPR‐Cas9 technology. Although several physical methods and viral vectors have been developed for CRISPR‐Cas9 delivery, their clinical application still suffers from disadvantages, such as the risks of mutagenesis, cell damage, and poor specificity. As an alternative, non‐viral nanocarriers hold great promise for circumventing these challenges. Furthermore, with aim to realize more efficient and precise genome editing and reduce the undesirable side effects, stimuli‐responsive nanocarriers are designed for the spatiotemporal CRISPR‐Cas9 delivery in responsive to various stimuli. In this review, we will summarize the recent progress in delivery strategies for CRISPR‐Cas9 genome editing. The mechanisms and advantages of these strategies were reviewed, providing a comprehensive review of the rational design of materials and techniques for efficient and precise genome editing. At last, the potential challenges of current CRISPR‐Cas9 delivery are discussed.