Fig. 2. Workflow and mechanism of action of ex vivo DC vaccines.

(A) The ex vivo generation of DC vaccines begins with leukapheresis to isolate peripheral blood mononuclear cells (PBMCs), followed by monocyte isolation and culture with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) to induce differentiation into immature DCs. These cells are then loaded with tumor-associated antigens such as peptides, mRNA, or tumor lysates and matured using cytokines or Toll-like receptor ligands before administration. (B) Mature DCs migrate to draining lymph nodes through CCR7-mediated homing, present antigenic peptides on MHC class I molecules to CD8⁺ T cells, and induce their activation and clonal expansion. Activated cytotoxic T lymphocytes infiltrate tumors and mediate targeted tumor cell killing.