Combination of Photodynamic Therapy and a Flagellin-Adjuvanted Cancer Vaccine Potentiated the Anti-PD-1-Mediated Melanoma Suppression

Cells

SheeEun Lee¹  Veena Vijayan²  Kondareddy Cherukula²  JoonHaeng Rhee³  YongJun Bang³  Sao Puth³  HyeSuk Hwang³  Jayalakshmi Thiruppathi³  MyeongJu Moon⁴  YongYeon Jeong⁴  In-Kyu Park⁴ 

[1] Clinical Vaccine R&D Center, Chonnam National University, Hwasun-gun, Jeonnam 58128, Korea;Department of Biomedical Sciences, Chonnam National University Medical School, Hwasun-gun, Jeonnam 58128, Korea;Department of Microbiology, Chonnam National University Medical School, Hwasun-gun, Jeonnam 58128, Korea;Department of Radiology, Biomolecular Theranostics (BiT) Laboratory, Chonnam National University Medical School, Hwasun-gun, Jeonnam 58128, Korea;

关键词: photodynamic therapy;    FlaB-adjuvanted peptide vaccine;    PD-1 blockade;    B16-F10 melanoma;    combination therapy;   

DOI  :  10.3390/cells9112432

来源: DOAJ

【 摘 要 】

Immune checkpoint inhibitors become a standard therapy for malignant melanoma. As immune checkpoint inhibitor monotherapies proved to have limited efficacy in significant portion of patients, it is envisaged that combination with other therapeutic modalities may improve clinical outcomes. We investigated the effect of combining photodynamic therapy (PDT) and TLR5 agonist flagellin-adjuvanted tumor-specific peptide vaccination (FlaB-Vax) on the promotion of PD-1 blockade-mediated melanoma suppression using a mouse B16-F10 implantation model. Using a bilateral mouse melanoma cancer model, we evaluated the potentiation of PD-1 blockade by the combination of peritumoral FlaB-Vax delivery and PDT tumor ablation. A photosensitizing agent, pheophorbide A (PhA), was used for laser-triggered photodynamic destruction of the primary tumor. The effect of combination therapy in conjunction with PD-1 blockade was evaluated for tumor growth and survival. The effector cytokines that promote the activation of CD8⁺ T cells and antigen-presenting cells in tumor tissue and tumor-draining lymph nodes (TDLNs) were also assayed. PDT and FlaB-Vax combination therapy induced efficacious systemic antitumor immune responses for local and abscopal tumor control, with a significant increase in tumor-infiltrating effector memory CD8⁺ T cells and systemic IFNγ secretion. The combination of PDT and FlaB-Vax also enhanced the infiltration of tumor antigen-reactive CD8⁺ T cells and the accumulation of migratory CXCL10-secreting CD103⁺ dendritic cells (DCs) presumably contributing to tumor antigen cross-presentation in the tumor microenvironment (TME). The CD8⁺ T-cell-dependent therapeutic benefits of PDT combined with FlaB-Vax was significantly enhanced by a PD-1-targeting checkpoint inhibitor therapy. Conclusively, the combination of FlaB-Vax with PDT-mediated tumor ablation would serve a safe and feasible combinatorial therapy for enhancing PD-1 blockade treatment of malignant melanoma.

【 授权许可】

Unknown