Dendritic cells modified by tumor associated antigen SMP30 have enhanced antitumor effect against mouse hepatocarcinoma cells in vitro and in vivo

Jinhong Guo; Yaoyao Zhang; Qiuhong Qin; Naixia Chao; Tianming Huang; Chengxiao Chen; Xiaoling Lu; Rongshi Huang; Jian Pan

Dendritic cells modified by tumor associated antigen SMP30 have enhanced antitumor effect against mouse hepatocarcinoma cells in vitro and in vivo

Am J Transl Res. 2022 Aug 15;14(8):5785-5799. eCollection 2022.

Authors

Jinhong Guo¹, Yaoyao Zhang², Qiuhong Qin³, Naixia Chao², Tianming Huang², Chengxiao Chen², Xiaoling Lu¹, Rongshi Huang⁴, Jian Pan⁵

Affiliations

¹ College of Stomatology, Hospital of Stomatology/Guangxi Key Laboratory of Nanobody Research/Guangxi Nanobody Engineering Research Center, Guangxi Medical University Nanning 530021, Guangxi, P. R. China.
² Department of Histology and Embryology, Guangxi Medical University Nanning 530021, Guangxi, P. R. China.
³ Department of Pathology, Jiangbin Hospital of Guangxi Zhuang Autonomous Region Nanning 530021, Guangxi, P. R. China.
⁴ Department of Histology and Embryology, Institute of Preclinical, Guangxi Traditional Chinese Medical University Nanning 530001, Guangxi, P. R. China.
⁵ Department of Human Anatomy, Guangxi Medical University Nanning 530021, Guangxi, P. R. China.

PMID: 36105050
PMCID: PMC9452339

Abstract

Objectives: Tumor immunotherapy based on dendritic cells (DC) is one of the most promising approaches to treat cancers. This therapy uses an immunogenic tumor antigen to present it to T cells. Senescence marker protein 30 (SMP30) is identified as a tumor associated antigen (TAA) with high immunogenicity and specificity for hepatocellular carcinoma (HCC). DCs are the most potent antigen presenting cells, and can be transduced with tumor antigens to enhance antitumor immune response. The purpose of this study was to investigate the antitumor effect of DCs transduced with a recombinant lentiviral vector (LV-SMP30) expressing SMP30.

Methods: A recombinant lentiviral vector (LV-SMP30) expressing SMP30 was constructed and transduced into DCs. The expression of SMP30 was detected by western blot. Mouse bone marrow-derived DCs were divided into four groups: LV-SMP30 group (transduced with LV-SMP30), Protein group (co-cultured with SMP30 protein), LV group (transduced with the empty vector) and Untreated group (the normal DCs). The effect of LV-SMP30 on DCs was detected through surface markers (CD123, CD11c, CD80 and CD86) and cytokine production. The activation and proliferation of CD3⁺CD8⁺ T cells were detected by CCK-8 kit. Flow cytometry was used to detect CD3⁺CD8⁺ T cell-mediated cytotoxicity. After construction of a mouse subcutaneous xenograft model, the volume and growth of tumors in different groups were observed. The changes in serum immune indexes in the treated groups were compared with those in the control group.

Results: The LV-SMP30 recombinant was constructed and transduced into DCs successfully, and LV-SMP30-transduced DCs stably expressed SMP30. The percentages of expression in the LV-SMP30 and Protein groups were significantly higher than those in the LV or Untreated groups (P<0.05). Meanwhile, after the DCs were cultured for 72 hours, the levels of IL-2, IL-6, IL-12, and IFN-γ were significantly higher in the LV-SMP30 and Protein groups than in the LV group or Untreated group (P<0.05). After the DCs were continuously cultured for one week, however, the cytokine levels in the LV-SMP30 group were significantly higher than those in the Protein group (P<0.05). In addition, CD3⁺CD8⁺ T cell proliferation and activation levels were substantially higher in the LV-SMP30 and Protein groups than in the LV or Untreated groups (P<0.05). Furthermore, as the ratio of effectors/target cells increasing in the LV-SMP30 group, CD3⁺CD8⁺ T cell-mediated cytotoxicity in H22 cells became higher (0:1, 10:1; 20:1; 40:1, respectively). In comparison to the control group, the cytotoxicity of the LV-SMP30 group was considerably increased at the ratios of 10:1, 20:1 and 40:1 (P<0.05). However, in the case of Hep1-6 cells, there was no significant difference in CD3⁺CD8⁺ T cell-mediated cytotoxicity among the groups. In addition, when compared with other groups, the mice in the LV-SMP30 group showed the most volume reduction, the slowest tumor growth, and the highest level of IL-2 and IFN-γ (P<0.05).

Conclusion: DCs transduced with LV-SMP30 can dramatically enhance specific CD3⁺CD8⁺ T cell immune responses against mouse hepatocarcinoma cells in vitro and in vivo. These findings lend significant support to the development of the DC-based SMP30 antigen vaccine for hepatocarcinoma immunotherapy.

Keywords: Dendritic cell; immunotherapy; lentivirus vector; senescence marker protein 30.