微囊化肾上腺细胞移植与生物可降解材料的临床应用

Transplantation of microencapsulated adrenocortical cells and clinical application of biodegradable materials

肾上腺细胞移植是治疗肾上腺皮质功能不全的一种新方法,但免疫排斥反应是限制细胞移植广泛应用的主要问题,微囊免疫隔离技术是克服免疫排斥反应的有效方法之一。微囊化细胞一方面有较好的免疫隔离作用,另一方面其半透膜表面可以容许小分子物质的通过,保证了囊内移植物的存活。海藻酸钙-聚赖氨酸-海藻酸钙是应用比较成熟的微囊材料,具有较好的生物相容性和机械稳定性,能提高细胞的生物活性和分泌功能。微囊的外径大小是影响其强度的主要因素,一般认为体积小且表面光滑的微囊比体积大的微囊强度高,不易破裂。但海藻酸钙-聚赖氨酸-海藻酸钙作为膜材料随着时间的延长,其囊本身有降解的可能,易引起囊周纤维化反应,选择合适的膜材料成为目前研究的焦点。随着组织工程技术的发展,以生物可降解材料聚β-羟基丁酸酯为载体的肾上腺细胞移植已经进入实验研究,研究发现该材是一种较好的细胞载体,可以促进移植细胞的生存、功能的恢复,有着广阔的应用前景。

Adrenocortical ceils transplantation is a newly developed method for treating adrenal insufficiency, which faces the key issue of immunological rejection. Immuisolation by encapsulation is one of the effective means for alleviating rejection due to its immuisolation effect, as well as the semipermeable membrane, which can guarantee the survival of grafts. Microcapsules made with alginate-polylysine-aiginate microencapsulation （APA） as immunoisotion membrane exhibit excellent biocompatibility and mechanical stability, which can elevate biological activity and secretion of cells. The intensity of microcapsules is determined by external diameter, generally speaking, microcapsule with small volume and smooth surface has stronger intensity than big volume microcapsule. However, APA may be degradation as time increasing, which easy to cause fibrosis. Therefore, it is necessary to find an immunoisotion membrane. The adrenocortical cells transplantation with biodegradable materials poly-β-hydroxybutyrate （PHB） as carriers arouses more and more attention. This material can promote the cell survival and function recovery, which has a wide application prospect.