Delivery of secretomes, which includes growth factors, cytokines, and mRNA, is critical in regenerative medicine for cell-to-cell communication. However, the harsh in vivo environment presents significant challenges for secretome delivery. Proteolytic enzymes shorten secretomes’ half-lives, and secretomes tend to rapidly diffuse at defect sites. Therefore, a delivery system that ensures prolonged retention and enhanced therapeutic efficacy of secretomes is required. In this study, a Coating Optimized Drug Delivery Enhancement (COD₂E) system, a coacervate composed of dopamine functionalized fucoidan and poly-l-lysine, was fabricated for secretome delivery. The dopamine modification significantly enhanced adhesive strength (>7-fold) compared to that of the neat coacervates, which enabled rapid (5 min) and uniform coating ability on collagen sponges. The COD₂E system was able to encapsulate fibroblast growth factor (FGF2) and prolong the half-life of FGF2. Notably, its efficacy, demonstrated through a single application of FGF2 encapsulated COD₂E on collagen sponge, in a wound model demonstrated a successful tissue repair. The COD₂E system is an effective growth factor delivery vehicle since it can protect growth factors, has an antioxidant ability, adheres on various material surfaces, and is hemocompatible.

中文翻译：

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用于增强生长因子生物半衰期的粘性聚电解质屏蔽层


分泌组（包括生长因子、细胞因子和 mRNA）的递送在细胞间通讯的再生医学中至关重要。然而，恶劣的体内环境给分泌组递送带来了重大挑战。蛋白水解酶会缩短分泌组的半衰期，分泌组往往会在缺陷部位迅速扩散。因此，需要一种确保分泌蛋白组延长保留时间并增强治疗效果的递送系统。在这项研究中，制备了一种包衣优化药物递送增强 （COD₂E） 系统，一种由多巴胺功能化岩藻多糖和聚-L-赖氨酸组成的凝聚物，用于分泌蛋白组递送。与纯凝聚物相比，多巴胺改性显著提高了粘合强度（>7 倍），从而能够在胶原蛋白海绵上实现快速（5 分钟）和均匀的涂层能力。COD₂E 系统能够封装成纤维细胞生长因子 （FGF2） 并延长 FGF2 的半衰期。值得注意的是，通过在胶原蛋白海绵上单次应用 FGF2 封装的 COD₂E 来证明其疗效，在伤口模型中证明了组织修复的成功。COD₂E 系统是一种有效的生长因子递送载体，因为它可以保护生长因子，具有抗氧化能力，粘附在各种材料表面，并且具有血液相容性。