Center for Sustainable Materials (SusMat), School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore, Singapore.
Bioinformatics Institute, Agency for Science, Technology and Research, 30 Biopolis Street, Matrix, 138671, Singapore, Singapore.
Nat Commun. 2024 Nov 21;15(1):10094. doi: 10.1038/s41467-024-54463-z.
Phase-separating peptides (PSPs) self-assembling into coacervate microdroplets (CMs) are a promising class of intracellular delivery vehicles that can release macromolecular modalities deployed in a wide range of therapeutic treatments. However, the molecular grammar governing intracellular uptake and release kinetics of CMs remains elusive. Here, we systematically manipulate the sequence of PSPs to unravel the relationships between their molecular structure, the physical properties of the resulting CMs, and their delivery efficacy. We show that a few amino acid alterations are sufficient to modulate the viscoelastic properties of CMs towards either a gel-like or a liquid-like state as well as their binding interaction with cellular membranes, collectively enabling to tune the kinetics of intracellular cargo release. We also demonstrate that the optimized PSPs CMs display excellent transfection efficiency in hard-to-transfect cells such as primary fibroblasts and immune cells. Our findings provide molecular guidelines to precisely program the material properties of PSP CMs and achieve tunable cellular uptake and release kinetics depending on the cargo modality, with broad implications for therapeutic applications such as protein, gene, and immune cell therapies.
相分离肽（PSPs）自组装成凝聚微滴（CMs）是一类很有前途的细胞内递药载体，可释放广泛治疗应用中部署的大分子模式。然而，CMs 的细胞内摄取和释放动力学的分子控制机制仍难以捉摸。在这里，我们系统地操纵 PSP 的序列，以揭示它们的分子结构、所得 CMs 的物理性质及其递药功效之间的关系。我们表明，少数氨基酸改变足以调节 CMs 的粘弹性性质，使其向凝胶状或液态转变，以及它们与细胞膜的结合相互作用，共同调节细胞内货物释放的动力学。我们还证明，优化的 PSPs CMs 在难以转染的细胞（如原代成纤维细胞和免疫细胞）中显示出优异的转染效率。我们的发现为精确调控 PSP CMs 的材料特性提供了分子指导，并根据货物模式实现了可调的细胞摄取和释放动力学，这对蛋白质、基因和免疫细胞治疗等治疗应用具有广泛的意义。
