Altering Antigen Charge to Control Self-Assembly and Processing of Immune Signals During Cancer Vaccination.

Biomaterial delivery systems offer unique potential to improve cancer vaccines by offering targeted delivery and modularity to address disease heterogeneity. Here, we develop a simple platform using a conserved human melanoma peptide antigen (Trp2) modified with cationic arginine residues that condenses an anionic toll-like receptor agonist (TLRa), CpG, into polyplex-like nanoparticles. We reasoned that these structures could offer several useful features for immunotherapy - such as tunable loading, co-delivery of immune cues, and cargo protection - while eliminating the need for synthetic polymers or other complicating delivery systems.