2025). AP-EVs were designed to activate tumor antigen-specific CD8+ T cells via the surface expression of the peptide–major histocompatibility complex class I (pMHCI) complex, CD80, and interleukin (IL)-2 on EVs, resulting in significant anti-tumor activity. Selectivity of AP-EVs facilitates the targeted delivery of IL-2 to antigen-specific CD8+ T cells, thereby promoting their in vivo expansion. The gene discussed is CD80; the disease is neoplasm.