Both polyclonal and monoclonal antibodies are useful for research and clinical applications. Monoclonal technology, however, makes reproducible, monospecific antibodies available for these procedures. Antigen-antibody reactions all require that antibody bind to antigen. Precipitation and agglutination reactions are examples of antibody binding to soluble or insoluble macromolecular antigens, respectively. Section 20.15 Allergy results when foreign antigens stimulate cellular or humoral immunity, and effector cells react so vigorously that host tissue is damaged by the resulting inflammation.
Autoimmunity results when the immune response reacts or cross-reacts with self antigens.
Superantigens cause massive over stimulation of the immune response and serious inflammatory consequences. Distinguish between hay fever and poison ivy allergies. Section 20.16 Immunity to infectious disease can be passive or active, natural or artificial. Immunization, a form of artificial active immunity, is widely employed to prevent infectious diseases. Most agents used for immunization are either attenuated or inactivated microorganisms or viruses, or inactivated forms of natural microbial products.