kuby immunology
8536d_ch01_001-023 8/1/02 4:25 PM Page 1 mac79 Mac 79:45_BW:Goldsby et al. / Immunology 5e:
Overview of the
Immune System
chapter 1
T
defense system that has evolved to protect animals from invading pathogenic microorganisms and cancer. It is able to generate an enormous variety of cells and molecules capable of specifically recognizing and eliminating an apparently limitless variety of foreign invaders. These cells and molecules act together in a dynamic network whose complexity rivals that of the nervous system.
Functionally, an immune response can be divided into two related activities—recognition and response. Immune recognition is remarkable for its specificity. The immune system is able to recognize subtle chemical differences that distinguish one foreign pathogen from another. Furthermore, the system is able to discriminate between foreign molecules and the body’s own cells and proteins. Once a foreign organism has been recognized, the immune system recruits a variety of cells and molecules to mount an appropriate response, called an effector response, to eliminate or neutralize the organism. In this way the system is able to convert the initial recognition event into a variety of effector responses, each uniquely suited for eliminating a particular type of pathogen. Later exposure to the same foreign organism induces a memory response, characterized by a more rapid and heightened immune reaction that serves to eliminate the pathogen and prevent disease.
This chapter introduces the study of immunology from an historical perspective and presents a broad overview of the cells and molecules that compose the immune system, along with the mechanisms they use to protect the body against foreign invaders. Evidence for the presence of very simple immune systems in certain invertebrate organisms then gives an evolutionary perspective on the mammalian immune system, which is the major
Overview of the
Immune System
chapter 1
T
defense system that has evolved to protect animals from invading pathogenic microorganisms and cancer. It is able to generate an enormous variety of cells and molecules capable of specifically recognizing and eliminating an apparently limitless variety of foreign invaders. These cells and molecules act together in a dynamic network whose complexity rivals that of the nervous system.
Functionally, an immune response can be divided into two related activities—recognition and response. Immune recognition is remarkable for its specificity. The immune system is able to recognize subtle chemical differences that distinguish one foreign pathogen from another. Furthermore, the system is able to discriminate between foreign molecules and the body’s own cells and proteins. Once a foreign organism has been recognized, the immune system recruits a variety of cells and molecules to mount an appropriate response, called an effector response, to eliminate or neutralize the organism. In this way the system is able to convert the initial recognition event into a variety of effector responses, each uniquely suited for eliminating a particular type of pathogen. Later exposure to the same foreign organism induces a memory response, characterized by a more rapid and heightened immune reaction that serves to eliminate the pathogen and prevent disease.
This chapter introduces the study of immunology from an historical perspective and presents a broad overview of the cells and molecules that compose the immune system, along with the mechanisms they use to protect the body against foreign invaders. Evidence for the presence of very simple immune systems in certain invertebrate organisms then gives an evolutionary perspective on the mammalian immune system, which is the major
References: Akira, S., K. Takeda, and T. Kaisho. 2001. Toll-like receptors: Critical proteins linking innate and acquired immunity Burnet, F. M. 1959. The Clonal Selection Theory of Acquired Immunity. Cambridge University Press, Cambridge. Cohen, S. G., and M. Samter. 1992. Excerpts from Classics in Allergy. Symposia Foundation, Carlsbad, California. Desour, L. 1922. Pasteur and His Work (translated by A. F. and B Fritig, B., T. Heitz, and M. Legrand. 1998. Antimicrobial proteins in induced plant defense Kimbrell, D. A., and B. Beutler. 2001. The evolution and genetics of innate immunity Kindt, T. J., and J. D. Capra. 1984. The Antibody Enigma. Landsteiner, K. 1947. The Specificity of Serologic Reactions. Harvard University Press, Cambridge, Massachusetts. Lawson, P. R., and K. B. Reid. 2000. The roles of surfactant proteins A and D in innate immunity Medawar, P. B. 1958. The Immunology of Transplantation. The Harvey Lectures 1956–1957 Medzhitov, R., and C. A. Janeway. 2000. Innate immunity. N. Metchnikoff, E. 1905. Immunity in the Infectious Diseases. Otvos, L. 2000. Antibacterial peptides isolated from insects. J. Paul, W., ed. 1999. Fundamental Immunology, 4th ed. Lippincott-Raven, Philadelphia.