++
KEY POINTS
-
Immunity is a series of delicately balanced, complex, multicellular, and physiologic mechanisms that allow an individual to distinguish foreign material from “self” and to neutralize and/or eliminate that foreign matter.
-
Innate immunity, which eliminates most potential pathogens before significant infection occurs, includes physical and biochemical barriers both inside and outside of the body as well as immune cells designed for specific responses.
-
Acquired immunity involves producing a specific immune response to each infectious agent (specificity) and remembering that agent so as to mount a faster response to a future infection by the same agent (memory).
-
Autoimmunity occurs when the reactions of the immune system are directed against the body’s own tissues, resulting in tissue damage and disease.
-
Hypersensitivity reactions require prior exposure leading to sensitization in order to elicit a reaction on subsequent challenge.
-
Immunotoxicology is the study of adverse effects of drugs, environmental chemicals, and, in some instances, biological materials on the immune system resulting from occupational, inadvertent, or therapeutic exposure.
-
Xenobiotics that alter the immune system can upset the balance between immune recognition and destruction of foreign invaders and the proliferation of these microbes and/or cancer cells.
++
Immunotoxicology can be defined as the study of adverse effects on the immune system resulting from occupational, inadvertent, or therapeutic exposure to drugs, environmental chemicals, and, in some instances, biological materials.
++
The immune system is a series of delicately balanced, complex, multicellular, and physiologic mechanisms that allow an individual to distinguish foreign material (i.e., “nonself”) from “self,” and to neutralize, eliminate, and/or coexist with the foreign matter. Examples of self are all the tissues, organs, and cells of the body. Examples of nonself include opportunistic bacteria and viruses, transformed cells or tissues (i.e., tumors), drugs, xenografts, or allergens. Immunotoxicology should be considered as a continuum (Fig. 12–1). Due to the potentially profound effects resulting from disruption of the delicately balanced immune system, there is a need to understand the cellular, biochemical, and molecular mechanisms of xenobiotic-induced immune modulation.
++++
The reader might also find the list of abbreviations in Table 12–1 helpful.
++