From site:
Immune Attacks content is geared for senior level high school biology and first year university biology.
To play the game, users control a microscopic robot and navigate through a first-person 3D body, completing a series of stepwise missions to detect a bacterial infection and activate the appropriate defensive immune cells. These stepwise missions follow the actual biological process that occurs during an infection and how immune cells are stimulated to kill the bacteria.
Note: This program is downloadable software for PC that requires a 3D graphics card.