Biology of Disease

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THE IMMUNE SYSTEM

4.1 Introduction

Theimmune system is a set of organs, tissues, cells and molecules that protect
the body from disease caused by microorganisms and multicellular parasites
(Chapter 2).Immunology is the study of the immune system and how it works.
Unraveling of the mechanisms of immune defense and the use of products of
the immune system in investigating and treating disease has revolutionized the
biomedical sciences in a way that is comparable to that of molecular biology
in recent years. This chapter describes the major components of the immune
system and explains how a coordinated immune response is produced against
infectious agents. In addition, the use of immunological techniques in the
biomedical sciences will be outlined.

OBJECTIVES

After studying this chapter you should be able to:

N give an account of the role of the immune system in maintaining health;

N explain the difference between nonspecific and specific immune

defenses;

N describe the cells of the immune system and outline their roles in immune

defense;

N explain the roles of major proteins involved in immune defense;

N describe the major features of inflammation and the acute phase

response;

N describe the major features of humoral and cell-mediated specific

immunity;

N outline the use of antibodies for detecting and quantifying molecules of

biomedical significance.