A bioparticle (left) ready to bind antigens (yellow) from tumor cells. Antigens are the unique small molecules found on viruses and other diseases that prompt the body to mount an immune defense. Once the antigens are bound to the bioparticle, they can activate the body’s immune system by interacting with T-cells (far right). Signaling proteins called cytokines embedded in the bioparticle (red) release slowly and help further stimulate the immune response. Credit: Nicolle Rager Fuller, NSF