[Discharge and Contents of Exosome from Leukocyte-Reduced Apheresis Platelet Stored for Different Storage Time].

To explore the effect of storage time on discharge and content of exosome from leukocyte-reduced apheresis platelets (LRA-Plt).Exosome (EXO) from LRA-Plt were acquired by ExoQuick, and its' morphology, immunological marker and particle size distribution were detected by transmission electron microscopy (TEM), Western blotting and dynamic light scattering (DLS), respectively. The changes in particle size distribution of EXO from LRA-Plt with different storage time were detected by DLS. The changes in content of protein and RNA of EXO from LRA-Plt with different storage time were detected by Nanodrop® ND-2000.EXO from LRA-Plt was acquired successfully, which was characterized by cup-like shape, CD63/TSG101 enriched and Calnexin negative, and the particle size of which ranged from 30 to 200 nm. At early stored stage (stored for 1 day and 2 days), particle size of EXO from LRA-Plt was small and ranges from 30 to 40 nm. Meanwhile, the contents of protein and RNA were low. The particle size distribution, contents of protein and RNA of EXO from LRA-Plt were not significanty different ammg groups (P＞0.05). At middle-late stored stage (stored for 3, 4 and 5 days), the particle size of EXO from LRA-Plt was larger than that of early stored stage, which ranges was from 130 to 200 nm. Meanwhile, the contents of protein and RNA were higher than those of early stored stage. Particle size distribution, contents of protein and RNA of EXO from LRA-Plt stored for middle-late stage were significant higher than those of early stored stage (P＜0.05).Morphology of EXO from LRA-Plt stored for middle-late stage was different from that stored for early stored stage. Moreover, the particle size distribution, contents of protein and RNA of EXO from LRA-Plt stored for middle-late stage were higher than those of early stored stage. A large amount of protein and RNA contained in EXO from LRA-Plt may participate in the multiple functions caused by platelet transfusion.不同储存时间的少白细胞单采血小板中外泌体释放及内容物.探讨不同储存时间对少白细胞单采血小板（leukocyte-reduced apheresis platelet，LRA-Plt）中外泌体（exosome，EXO）释放及内容物的影响.应用ExoQuick获得不同储存时间对LRA-Plt中的EXO，采用透射电镜术（transmission electron microscopy，TEM）、蛋白免疫印迹法、动态光散射（Dynamic Light Scattering，DLS）法分别进行形态、免疫标记、粒径分布检测。应用DLS检测不同储存时间LRA-Plt中EXO的粒径分布变化，通过Nanodrop® ND-2000检测不同储存时间LRA-Plt中EXO的蛋白和RNA含量变化.成功获取类杯状、CD63/TSG101富集、Calnexin阴性、直径分布在30-200 nm的LRA-Plt来源EXO。储存早期（储存d 1、2），LRA-Plt来源EXO的粒径较小，分布多在30-40 nm；蛋白和RNA含量较低；2组间粒径分布、蛋白和RNA含量无显著差异（P＞0.05）。储存中晚期，LRA-Plt来源EXO的粒径较储存早期大，分布多在130-200 nm；蛋白和RNA含量较早期显著上升；与储存早期相比，储存中晚期LRA-Plt中EXO在粒径分布、蛋白和RNA含量上均出现显著上升（P＜0.05）.储存中晚期的LRA-Plt中EXO形态与储存早期存在差异，且粒径分布、蛋白和RNA含量显著高于储存早期。EXO携带的大量蛋白和RNA可能参与了血小板输注后多种功能作用的执行.