Department of Antibody Engineering, Genentech Inc., South San Francisco, CA, United States of America.
PLoS One. 2024 Sep 3;19(9):e0305848. doi: 10.1371/journal.pone.0305848. eCollection 2024.
Intracellular delivery of large molecule cargo via cell penetrating peptides (CPPs) is an inefficient process and despite intense efforts in past decades, improvements in efficiency have been marginal. Utilizing a standardized and comparative analysis of the delivery efficiency of previously described cationic, anionic, and amphiphilic CPPs, we demonstrate that the delivery ceiling is accompanied by irreparable plasma membrane damage that is part of the uptake mechanism. As a consequence, intracellular delivery correlates with cell toxicity and is more efficient for smaller peptides than for large molecule cargo. The delivery of pharmaceutically relevant cargo quantities with acceptable toxicity thus seems hard to achieve with the CPPs tested in our study. Our results suggest that any engineered intracellular delivery system based on conventional cationic or amphiphilic CPPs, or the design principles underlying them, needs to accept low delivery yields due to toxicity limiting efficient cytoplasmic uptake. Novel peptide designs based on detailed study of uptake mechanisms are required to overcome these limitations.
通过细胞穿透肽 (CPP) 将大分子货物递送到细胞内是一个低效的过程，尽管在过去几十年中进行了大量努力，但效率的提高仍然微不足道。利用对以前描述的阳离子、阴离子和两亲性 CPP 的递药效率进行标准化和比较分析，我们证明递药上限伴随着不可修复的质膜损伤，这是摄取机制的一部分。因此，细胞内递药与细胞毒性相关，对于较小的肽而言比对于大的分子货物更有效。用我们研究中测试的 CPP 以可接受的毒性实现具有治疗相关货物数量的递药似乎很难。我们的结果表明，任何基于传统阳离子或两亲性 CPP 的或基于其设计原理的工程化细胞内递药系统都需要接受由于毒性限制有效细胞质摄取而导致的低递药效率。需要基于对摄取机制的详细研究的新型肽设计来克服这些限制。
