Dendritic cell-based cancer vaccines (DC vaccines) have been proved efficient and safe in immunotherapy of various cancers, including melanoma, ovarian and prostate cancer. However, the clinical responses were not always satisfied. Here we proposed a novel strategy to prepare DC vaccines. In the present study, a fusion protein SNU containing a secretin-penetratin (SecPen) peptide, NY-ESO-1 and ubiquitin was designed and expressed. To establish the DC vaccine (DC-SNU), the mouse bone marrow-derived DCs (BMDCs) were isolated, pulsed with SNU and maturated with cytokine cocktail. Then peripheral blood mononuclear cells (PBMCs) from C57BL/6 mice inoculated intraperitoneally with DC-SNU were separated and cocultured with MC38/MC38^NY-ESO-1 tumor cells or DC vaccines. The results show that SNU was successfully expressed. This strategy made NY-ESO-1 entering cytoplasm of BMDCs more efficiently and degraded mainly by proteasome. As we expected, mature BMDCs expressed higher CD40, CD80 and CD86 than immature BMDCs. Thus, the PBMCs released more IFN-γ and TNF-α when stimulated with DC-SNU in vitro again. What's more, the PBMCs induced stronger and specific cytotoxicity towards MC38^NY-ESO-1 tumor cells. Given the above, it demonstrated that DC-SNU loaded with SecPen and ubiquitin-fused NY-ESO-1 could elicit stronger and specific T cell immune responses. This strategy can be used as a platform for DC vaccine preparation and applied to various cancers treatment.

基于树突细胞的癌症疫苗（DC疫苗）已被证明在各种癌症（包括黑素瘤，卵巢癌和前列腺癌）的免疫疗法中是有效且安全的。但是，临床反应并不总是令人满意的。在这里，我们提出了制备DC疫苗的新策略。在本研究中，设计并表达了一种融合蛋白SNU，它含有促胰液素-渗透素（SecPen）肽，NY-ESO-1和泛素。为了建立DC疫苗（DC-SNU），分离小鼠骨髓来源的DC（BMDC），用SNU脉冲并用细胞因子混合物成熟。然后分离腹膜内接种DC-SNU的C57BL / 6小鼠的外周血单个核细胞（PBMC），并与MC38 / MC38 ^NY-ESO-1共培养肿瘤细胞或DC疫苗。结果表明成功表达了SNU。这种策略使NY-ESO-1更有效地进入BMDC的细胞质，并主要被蛋白酶体降解。正如我们预期的那样，成熟的BMDC的CD40，CD80和CD86高于未成熟的BMDC。因此，PBMC中IFN-更释放γ和TNF- α在与DC-SNU刺激体外试。此外，PBMC对MC38 ^NY-ESO-1肿瘤细胞产生更强的特异性细胞毒性。鉴于上述情况，它证明了装载SecPen和泛素融合的NY-ESO-1的DC-SNU可以引发更强的特异性T细胞免疫反应。该策略可以用作DC疫苗制备的平台，并应用于各种癌症治疗。