人脐带间充质干细胞来源的外泌体免疫调节功能异质性研究

目的 研究不同供者来源的人脐带间充质干细胞(hUC-MSC)分泌的外泌体免疫调节能力的异质性.方法 培养5株不同供者来源的hUC-MSC,收集无血清培养上清提取外泌体,流式细胞术检测其表面特异性标志CD9、CD63、CD81、CD44的表达,BCA法测定总蛋白含量.将外泌体和脐带血单个核细胞(UBMC)共培养72 h,MTT实验检测细胞增殖活性, ELISA测定共培养上清中干扰素γ(IFN-γ)和肿瘤坏死因子α(TNF-α)的含量.离心重悬UBMC和K562细胞按5∶1的比例共培养4 h,MTT实验检测细胞活性,计算UBMC的杀伤能力.结果 提取的外泌体表达CD9,CD63,CD81及CD44.不同供者来源hUC-MSC分泌的外泌体对UBMC的增殖、分泌细胞因子及K562细胞杀伤能力的作用不同.结论 不同供者hUC-MSC的外泌体免疫调节能力具有异质性.

Heterogeneity of immunomodulatory function of exosomes derived from human umbilical cord mesenchymal stem cells

Objective To investigate the heterogeneity of immunomodulatory function of exosomes secreted from human umbilical cord-derived mesenchymal stem cells(hUC-MSC).Methods Five different hUC-MSCs lines were isolated and cultured.Exosomes were isolated from the supernatant.The expression of specific surface markers CD9,CD63,CD81 and CD44 was detected by flow cytometry.The protein concentration of hUC-MSCs exosomes(hUC-MSCs-ex)was evaluated by the BCA assay.Concanavalin A and rhIL-2 stimulated umbilical cord blood mononuclear cells (UBMCs) from healthy donor were co-cultured at different concentrations of hUC-MSCs-ex from different cell lines for 72 h.The growth rate of UBMCs was detected by MTT assay.ELISA was used to test the levels of IFN-γ and TNF-α of the supernatants.The UBMCs co-cultured with hUC-MSCs were co-cultured with K562 cells at the ratio of 5∶1.The cytotoxic activity was calculated by MTT assay.Results hUC-MSCs-ex expressed CD9,CD63,CD81and CD44.Different hUC-MSCs lines had different regulating activities on the proliferation,secretion and killing ability of UBMCs.Conclusion hUC-MSCs-ex has heterogeneity of immunomodulatory function on UBMCs.