Immune system allergic responses

Allergic response The release of antibodies by the immune system in response to foreign molecules in the body. 

The adaptive immune system is responsible for the occurrence of drug allergies after applying certain chemicals for example to the skin. Symptoms of such allergic hypersensitivities are observed only in the elicitation phase and not in the preceding sensitization phase, as only the second exposure to the causative drug results in T cell- or antibody-mediated adverse effects. 

Allergic contact dermatitis Skin condition that occurs in response to exposure to sensitizing material. It is characterized by redness, swelling and cracking and, sometimes more severe reactions involving the entire immune system. 

In addition to its role in preventing scurvy (see Human Biochemistry box Ascorbic Acid and Scurvy and also Chapter 6), ascorbic acid also plays important roles in the brain and nervous system. It also mobilizes iron in the body, prevents anemia, ameliorates allergic responses, and stimulates the immune system. 

As a bacterial protein, streptokinase is viewed by the human immune system as an antigenic substance. In some cases, its administration has elicited allergic responses that have ranged from mild rashes to more serious anaphylactic shock (an extreme and generalized allergic response characterized by swelling, constriction of the bronchioles, circulatory collapse and heart failure). 

The regulation of mast-cell activity by biologically active peptides is an area of research, the rapid growth of which has been sparked in part by this intense interest in the interactions between neural, endocrine and immune systems [4, 26, 41] and in part by the recognition that activation of mast-cell secretion as a purely allergic IgE-dependent event is undoubtedly too restrictive. The involvement of the mast cell in the inflammatory response, for example, has for years been suspected to involve a number of non-immunologic, IgE-inde-pendent factors [24,42], Direct evidence for peptide involvement, however, has... 

The US-EPA OPPTS test guideline on immunotoxicity (OPPTS 870.7800) provides the following definition Immunotoxicity refers to the ability of a test substance to suppress immune responses that could enhance the risk of infectious or neoplastic disease, or to induce inappropriate stimulation of the immune system, thus contributing to allergic or autoimmune disease. ... 

The answer is E. Immune responses involving the soluble antibody or humoral system are initiated first in IgM class. Long-term immunity is mediated by IgG molecules that circulate in the plasma. Acute allergic responses frequently involve increased levels of IgE molecules. 

Allergic reaction—An abnormal response by the body s immune system. 

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