How Innate and Adaptive Immunity Work

The immune system encompasses two parallel and complementing activities, innate and adaptive immunity. When a dangerous event occurs or an agent is sensed as a danger, first innate immunity and later adaptive immunity get activated for defending the organism from damage. This chapter will introduce the reader to the basic concepts of immunity and how immunity acts in defending and maintaining the body's physical and functional integrity. The putative challenge posed by nanoparticles will be examined within this framework. © 2014 Elsevier Inc. All rights reserved.