Xinyuan Institute of Medicine and Biotechnology, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China.
Shanghai Cell Therapy Research Institute, Shanghai 201805, China.
J Immunol Res. 2020 Apr 4;2020:3965061. doi: 10.1155/2020/3965061. eCollection 2020.
The success of peptide-based dendritic cell (DC) cancer vaccines mainly depends on the utilized peptides and selection of an appropriate adjuvant. Herein, we aimed to evoke a broad immune response against multiple epitopes concurrently in the presence of immunoadjuvant. Three synthetic HLA-A∗0201-restricted peptides were separately linked with HMGB1-derived peptide (SAFFLFCSE, denoted as HB) as immunoadjuvant via double arginine (RR) linker and loaded onto human monocyte-derived DCs. Peptide uptake was detected by immunofluorescence microscopy and flow cytometry. The maturation and activation status of pulsed DCs were monitored by detection of the expression of specific markers and released cytokines. The ability of peptide-pulsed DCs to activate allogeneic T cells has been assessed by a degranulation assay and detection of secreted cytokines. The lytic activity of effector T cells against cancer cells in vitro was analyzed by a lactate dehydrogenase (LDH) assay. Results revealed that DCs efficiently take up peptides+HB and expressed higher levels of surface markers (HLA-ABC, HLA-DR, CD80, CD86, CD83, CD40, and CCR7) and proinflammatory cytokines (IL-6, IFN-, TNF-, and IL-12) than control DCs, free peptide-pulsed DCs, and free HB-pulsed DC groups. Moreover, peptides+HB/pulsed DCs were capable of activating allogeneic T cells and enhance their lytic activity against a pancreatic cancer cell line (PANC-1) in vitro. These findings suggest that antigenic peptides covalently linked with HB/pulsed DCs could be a promising strategy to improve the current DC-based cancer vaccines.
基于肽的树突状细胞（DC）癌症疫苗的成功主要取决于所使用的肽和适当佐剂的选择。在此，我们旨在在免疫佐剂存在的情况下，同时针对多个表位引发广泛的免疫反应。三种合成的 HLA-A*0201 限制性肽分别通过双精氨酸（RR）接头与 HMGB1 衍生肽（SAFFLFCSE，记为 HB）连接，并负载于人单核细胞衍生的 DC 上。通过免疫荧光显微镜和流式细胞术检测肽摄取。通过检测特异性标记物的表达和释放的细胞因子来监测脉冲 DC 的成熟和激活状态。通过脱颗粒测定和检测分泌的细胞因子来评估肽脉冲 DC 激活同种异体 T 细胞的能力。通过乳酸脱氢酶（LDH）测定分析效应 T 细胞在体外对癌细胞的裂解活性。结果表明，DC 能够有效摄取肽+HB，并表达更高水平的表面标记物（HLA-ABC、HLA-DR、CD80、CD86、CD83、CD40 和 CCR7）和促炎细胞因子（IL-6、IFN-γ、TNF-α 和 IL-12），比对照 DC、游离肽脉冲 DC 和游离 HB 脉冲 DC 组更高。此外，肽+HB/脉冲 DC 能够激活同种异体 T 细胞，并增强其对体外胰腺癌细胞系（PANC-1）的裂解活性。这些发现表明，与 HB 共价连接的抗原肽脉冲 DC 可能是提高当前基于 DC 的癌症疫苗的有前途的策略。
