immunogen
A molecule that has the ability to evoke B- and/or T-cell mediated immune reaction.

immunoglobulin
A protein that acts as an antibody.

immunosuppression
The suppression of the normal response of the immune system to an antigen.

immunotherapy
Treatment that uses the body’s natural defenses to fight disease.

inoculation
Taking a vaccine as a precaution against contracting a disease.

interstitial
Between the grains (or cells or other solid objects). Having to do with the small, narrow spaces (called interstices) found in between grains of sand, large cells or atoms or molecules, different tissues in the body, or within soil. The pores between different minerals in a rock, or (in crystallography) the areas in a crystal which are not lattice sites.

irradiation
The use of high-energy radiation from x-rays, neutrons, and other sources to kill cancer cells and shrink tumors.