1 - Perspective on Immunity and Immunology

Abstract

Immunology is the study of the immune system. The immune system is the body's defense system against invasion by non-self entities, including infectious and inert agents, and tumor cells. The normal functioning of the immune system gives rise to immunity. Immunology overlaps more and more with the strictly delineated fields of pathology, biochemistry, and genetics. Immunology is complex and challenging, but it is also essential and fascinating. This chapter describes the involvement of the immune system in defense against pathogens and cancers and highlights its roles in promoting allergy, transplant rejection, and autoimmunity. It also discusses inherited and acquired defects in immunity as well as tumors arising in immune system cells. Thus, the chapter provides an understanding of the cellular and molecular mechanisms underlying immunity, how these mechanisms can go awry to cause disease, and how researchers seek to manipulate these mechanisms with the goal of ensuring good health for all. As the malfunction of the immune system underlies many aspects of human disease, including cancer, autoimmune disorders, allergy, hypersensitivity, transplantation rejection, and immunodeficiency, the immune system is therefore the central player in the maintenance of human health and disease.