Immune: A Journey into the Mysterious System That Keeps You Alive

The human immune system is very complex and continues to evolve as the different invaders evolve. This book presents the science behind the immune system in an easy to understand format, mixing scientific terminology with analogies. For example, cancer is similar to rogue developers constructing skyscrapers in Brooklyn, plucking down il-constructed buildings wherever they see fit. At first it might be cute, but pretty soon they dominate and there is no other place for people to live. 

There are many layers in the immune response. The body also has the ability to respond to just about any invader. However, the response is usually not immediate. A "too good" immune system can be just as bad as a "too bad" one. Allergic reactions and anaphylactic shock are usually caused by the immune system working too hard when it does not need to.

Fevers and other "symptoms" of sickness are part of the body's way of fighting the invader. The skin provides a huge barrier that makes it difficult for different pathogens to enter the body. Once something is in, different cells attempt to fight it off, depending on the nature. Viruses use the body's cells to replicate themselves. The body's defences involve matching signatures and also killing off items that are not properly identifying themselves. There are many battles going on everyday as our immune system fights to keep us alive.