When administered, peptide-based vaccines introduce these short peptide sequences into the body. The peptides are taken up by antigen-presenting cells (APCs), such as dendritic cells, which process and present the peptides on their surface via major histocompatibility complex (MHC) molecules. This presentation activates T cells, particularly cytotoxic T lymphocytes (CTLs) and helper T cells, leading to a targeted immune response against the pathogen.
