Li Zhichao, Xue Guoliang, Wei Zhigang, Ye Xin
Department of Oncology, The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Shandong Key Laboratory of Rheumatic Disease and Translational Medicine, Shandong Lung Cancer Institute, Jinan, Shandong, China.
J Cancer Res Ther. 2022 Sep;18(5):1292-1298. doi: 10.4103/jcrt.jcrt_2291_21.
This study was conducted to explore the high-intensity focused ultrasound (HIFU) prepared antigen-sensitized dendritic cells (DC) and the induction of cytotoxic T lymphocyte (CTL) killing effects by DC and to observe their anti-tumor immunity effects on BALB/c mice.
GM-CSF and IL-4 were used to culture the mouse bone marrow-derived DC. HIFU was used to prepare CT-26 tumor cell antigen-sensitive DC vaccines. The capability of T cell proliferation was detected by H-TdR, and the CTL cytotoxicity was detected using standard 4hCr release assay. The DC-based tumor vaccine prepared using HIFU irradiation was given to normal BALB/c mice. The mice were injected with CT-26 cancer cells subcutaneously seven days later. Further, the occurrence time of the tumor, its weight and volume on the 20 day was observed, and the allergic DC group challenged using repeated-freezing-thawing method alone with the normal saline control group (negative control group) were used to compare group differences.
DC in the HIFU group, tumor cell freeze-thawing group, tumor supernatant group, and phosphate buffer solution (PBS) group could induce T cell proliferation in vitro. However, the ability to induce T cell proliferation of DC in the HIFU group and tumor cell freeze-thawing group was significantly higher than those in the tumor supernatant and PBS groups (P < 0. 05). CTL induced in vitro by DC in the HIFU group, and the tumor cell freeze-thawing group had significant cytotoxicity to colon cancer, being significantly different from those in the tumor supernatant and PBS groups (P < 0.05). There was no significant difference between the cytotoxicity of CTL induced in vitro in the HIFU group and the tumor cell freeze-thawing group (P > 0.05). Additionally, significant differences in the occurrence time of the tumor, its weight and volume on the 20 day, and the median survival time of mice among the HIFU group, the repeated-freezing-thawing group, and the negative control group were observed (P < 0.01 or P < 0.05). There was a significant difference between the HIFU and the repeated-freezing-thawing group (P < 0.05).
HIFU prepared antigen-sensitized DC could cause substantial proliferation of T cells and CTL with strong anti-tumor effects. The DC-based tumor vaccine prepared using HIFU irradiation affected active immunization on the tumor occurrence in vitro and was better than the DC-based tumor vaccine prepared using the repeated-freezing-thawing method.
本研究旨在探讨高强度聚焦超声（HIFU）制备的抗原致敏树突状细胞（DC）及其诱导细胞毒性T淋巴细胞（CTL）杀伤效应，并观察其对BALB/c小鼠的抗肿瘤免疫作用。
采用GM-CSF和IL-4培养小鼠骨髓来源的DC。利用HIFU制备CT-26肿瘤细胞抗原敏感的DC疫苗。通过H-TdR检测T细胞增殖能力，采用标准的4hCr释放试验检测CTL细胞毒性。将经HIFU照射制备的基于DC的肿瘤疫苗给予正常BALB/c小鼠。7天后皮下注射CT-26癌细胞。进一步观察肿瘤的发生时间、第20天的重量和体积，并将单独采用反复冻融法激发的过敏DC组与生理盐水对照组（阴性对照组）进行比较，观察组间差异。
HIFU组、肿瘤细胞冻融组、肿瘤上清组和磷酸盐缓冲液（PBS）组的DC均可在体外诱导T细胞增殖。然而，HIFU组和肿瘤细胞冻融组的DC诱导T细胞增殖的能力显著高于肿瘤上清组和PBS组（P<0.05）。HIFU组和肿瘤细胞冻融组的DC体外诱导的CTL对结肠癌具有显著的细胞毒性，与肿瘤上清组和PBS组的CTL细胞毒性有显著差异（P<0.05）。HIFU组和肿瘤细胞冻融组体外诱导的CTL细胞毒性之间无显著差异（P>0.05）。此外，观察到HIFU组、反复冻融组和阴性对照组在肿瘤发生时间、第20天的肿瘤重量和体积以及小鼠的中位生存时间方面存在显著差异（P<0.01或P<0.05）。HIFU组与反复冻融组之间存在显著差异（P<0.05）。
HIFU制备的抗原致敏DC可引起T细胞和CTL大量增殖，具有较强的抗肿瘤作用。采用HIFU照射制备的基于DC的肿瘤疫苗对体外肿瘤发生有主动免疫影响，优于采用反复冻融法制备的基于DC的肿瘤疫苗。
