ABSTRACT
This chapter is designed to introduce the reader to general concepts and nomenclature as a preparation for the chapters that follow. The chapter starts with a brief digression on the history and evolution of immunology followed by an overview of general concepts about specific and nonspecific defenses, characteristics, and stages of the adaptive immune response and a general discussion of the cells involved in the adaptive immune response. The characteristics of antigens and antibodies are reviewed, with special emphasis on the involvement of different populations of lymphocytes in defense mechanisms of cell-mediated immunity as well as in adverse hypersensitivity reactions. The concepts of self versus non-self discrimination, tolerance, and immunogenicity are briefly presented followed by a general overview of the different stages and elements involved in an adaptive immune response. The chapter ends with a brief discussion of the impact of immunology in clinical medicine.
