The immune system has a series of dual natures, the most important of which is self/non-self recognition. There are two types of immunity—innate (non-specific) and specific (adaptive) immunity. The innate immunity system is what we are born with and it is non-specific (Table 7.1). All types of antigens are attacked pretty much equally present in all normal humans. It is genetically based and we pass it on to our offspring. The human body has various methods of defence which are as ...