Fig. 3

Mechanism of cancer vaccines. Compared to peptide-based vaccines, nucleic acid-based vaccines need more processing steps after entering the body before being presented to T cells by DCs. However, DNA and RNA vaccines are better suited to deliver MHC I presentation antigens than peptide vaccines. Tumor antigens are processed by DCs and transported to the cell surface of MHC I and MHC II molecules. Interaction between MHC–peptide complex–T cell receptor (TCR) and cognate receptor-ligand pairs activate T cells. Activated CD4⁺ T cells induce B cells to differentiate into plasma cells and memory B cells. Activated T cells differentiated into CD8⁺ memory T cells and CD8⁺ effector T cells. Eventually, effector T cells, B cells, antibodies, and some cytokines kill tumor cells directly or indirectly