keyhole limpet hemocyanin (KEE-hole LIM-pet HEE-moh-SY-uh-nin)
A substance taken from a marine organism that may be linked to a specific antigen to boost the immune response to that antigen. Keyhole limpet hemocyanin is being studied as a way to increase the immune response to cancer vaccines. It is a type of immune modulator. Also called KLH.