| 
                                Definition | 
                            
                                Preparations containing substances with antigenic properties administered to activate the immune system, thereby inducing an immune response./CTEP Definition: A substance or group of substances administered to induce the immune system to recognize and destroy tumors or microorganisms, which can be used for prevention, amelioration, or treatment of diseases./NCI-GLOSS Definition: A substance or group of substances meant to cause the immune system to respond to a tumor or to microorganisms, such as bacteria or viruses. A vaccine can help the body recognize and destroy cancer cells or microorganisms.
                             |