Innate immunity

This chapter opens with a discussion on pattern-recognition by the innate immune system. It points out that one of the key roles of the innate immune system is to distinguish between self and non-self, and where possible between self and pathogen. The chapter then argues that the recognition is mediated by the interaction of two sets of complementary molecules: pathogen-associated molecular patterns (PAMPs) and pattern-recognition receptors (PRRs). The chapter also assesses the intracellular responses triggered by pathogen or damage recognition. It also describes and displays some examples of humoral innate immune mechanism and mediators of innate immunity. Finally, the chapter uncovers the three cells of innate immunity: phagocytic cells, dendritic cells, and mast-cells. It then explains the purpose of acute inflammation and the cellular interactions between the adaptive and innate immunity systems.