胃腺癌BGC-823细胞总RNA转染人树突状细胞分泌exosomes的抗肿瘤效应研究

Antitumor induced by exosomes derived from human dendritic cell transfected with BGC-823 cell total RNA

目的研究人外周血树突状细胞(DC)体外经人胃腺癌BGC-823细胞系总RNA转染后,提取培养上清液中DC分泌的外泌体(exosomes),诱导出特异性抗胃癌效应。方法分离外周血单核细胞,经GM-CSF、IL-4培养5 d后,获得未成熟DC(imDC);体外以脂质体转染BGC-823细胞总RNA。第7天收集上清,利用超速离心法提取exosomes。分别将DC以及exosomes与T淋巴细胞共培养3 d,获得细胞毒T淋巴细胞(CTL),检测CTL对BGC-823细胞的杀伤作用。结果与未转染组相比,转染BGC-823总RNA DC来源的exosomes明显促进T细胞对BGC-823的杀伤活性(P<0.05)。结论应用BGC-823总RNA转染DC分泌exosomes能够诱导出强烈的抗肿瘤免疫反应。

Objective To investigate effect of exosomes derived from human monocyte-derived dendritic cells （DC） transfected with BGC-823 cell total RNA on induction of antigen-specific CTL responses in vitro. Methods DC were generated from healthy volunteers peripheral blood mononuclear cells （PBMC）. PBMC were cultured by GM-CSF and IL-4 for 5 days. BGC-823 cell total RNA was transfeeted with lipofectamine 2000 in vitro. Exosomes were extracted with supematant 7 days later. After DC and exosomes were co-cultured with autologous T cells for 3 days, the T cells were activated to tumor specific cytotoxic T lympho- cytes （CTL）. The inhibition of CTL on BGC-823 cells was detected by using MTT assay. Results Compared with exosomes de- rived from none-transfected DC, exosomes derived from DC transfected with BGC-823 cell total RNA significantly promoted the a- bility of T lymphecytes to kill target BGC-823 cells. Conclusions Exosomes derived from DC transfected with BGC-823 cell total RNA could induce effective immune responses and may be used to induce tumor-specific immunity.