TRF adjuvant enhances dendritic cell vaccine efficacy in a Murine breast cancer model

Dendritic cells (DCs) are immune cells that can present antigens to T-cells and stimulate immune responses. Tocotrienol-rich fraction (TRF) from palm oil has been reported to have anti-cancer and immune-enhancing effects. In this study, TRF was used as an adjuvant to augment the efficacy of DC vaccines in treating mouse mammary cancer. The results revealed that early treatment of TRF and DC vaccine significantly improved the prognosis of the mice with cancer. We also found that the tumours in the animals treated at the G1 stage had lower volume than those in the other groups. Interferon-gamma (IFN-γ) and interleukin-12 (IL-12) productions showed the highest level in the group exposed to the earliest vaccine therapy and combination with TRF. A similar pattern for tumour inhibition was observed in other groups. Furthermore, PD-1 and PD-L1 were significantly down-regulated in the earlier treatment compared to the one that was received at a later stage. The higher interactions of cell surface proteins (PD1 and PD-L1) elevate the progression of tumours in the tumour microenvironment. Therefore, early treatment inhibited the interaction of cell surface proteins in the tumour microenvironment. In conclusion, TRF can be used as an adjuvant to enhance tumour-specific immune response induced by DC-based vaccines in a syngeneic mouse model of breast cancer.rlier treatment modality exposure to the mouse model warranted the best inhibition in tumour-bearing mice and increased anti-tumour immune response. Hence, DC-based vaccines and TRF as adjuvant may be clinically useful as a new immunotherapeutic approach towards cancers.