School of Medicine, University of Electronic Science and Technology of China, Chengdu, China.
Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland.
Front Immunol. 2022 Apr 14;13:869984. doi: 10.3389/fimmu.2022.869984. eCollection 2022.
Islet transplantation is a promising approach for the treatment of type 1 diabetes (T1D). Currently, clinical islet transplantation is limited by allo - and autoimmunity that may cause partial or complete loss of islet function within a short period of time, and long-term immunosuppression is required to prevent rejection. Encapsulation into semipermeable biomaterials provides a strategy that allows nutrients, oxygen and secreted hormones to diffuse through the membrane while blocking immune cells and the like out of the capsule, allowing long-term graft survival and avoiding long-term use of immunosuppression. In recent years, a variety of engineering strategies have been developed to improve the composition and properties of encapsulation materials and to explore the clinical practicality of islet cell transplantation from different sources. In particular, the encapsulation of porcine islet and the co-encapsulation of islet cells with other by-standing cells or active ingredients for promoting long-term functionality, attracted significant research efforts. Hydrogels have been widely used for cell encapsulation as well as other therapeutic applications including tissue engineering, cell carriers or drug delivery. Here, we review the current status of various hydrogel biomaterials, natural and synthetic, with particular focus on islet transplantation applications. Natural hydrophilic polymers include polysaccharides (starch, cellulose, alginic acid, hyaluronic acid, chitosan) and peptides (collagen, poly-L-lysine, poly-L-glutamic acid). Synthetic hydrophilic polymers include alcohol, acrylic acid and their derivatives [poly (acrylic acid), poly (methacrylic acid), poly(acrylamide)]. By understanding the advantages and disadvantages of materials from different sources and types, appropriate materials and encapsuling methods can be designed and selected as needed to improve the efficacy and duration of islet. Islet capsule transplantation is emerging as a promising future treatment for T1D.
胰岛移植是治疗 1 型糖尿病 (T1D) 的一种很有前途的方法。目前，临床胰岛移植受到同种异体和自身免疫的限制，这可能导致胰岛功能在短时间内部分或完全丧失，并且需要长期免疫抑制来防止排斥反应。将胰岛封装到半透性生物材料中提供了一种策略，允许营养物质、氧气和分泌的激素通过膜扩散，同时将免疫细胞等阻挡在胶囊外，从而实现长期移植物存活并避免长期使用免疫抑制剂。近年来，已经开发出多种工程策略来改善封装材料的组成和特性，并从不同来源探索胰岛细胞移植的临床实用性。特别是，猪胰岛的封装以及与其他旁观细胞或促进长期功能的活性成分的共封装，引起了广泛的研究关注。水凝胶已广泛用于细胞封装以及其他治疗应用，包括组织工程、细胞载体或药物递送。在这里，我们综述了各种天然和合成的水凝胶生物材料的现状，特别是针对胰岛移植应用。天然亲水性聚合物包括多糖（淀粉、纤维素、藻酸盐、透明质酸、壳聚糖）和肽（胶原蛋白、聚赖氨酸、聚谷氨酸）。合成亲水性聚合物包括醇、丙烯酸及其衍生物[聚丙烯酸、聚甲基丙烯酸、聚丙烯酰胺]。通过了解来自不同来源和类型的材料的优缺点，可以根据需要设计和选择合适的材料和封装方法，以提高胰岛的疗效和持续时间。胰岛胶囊移植作为 T1D 的一种有前途的未来治疗方法正在出现。
