The immune system is one of the most complex systems in the human body, it has the ability to recognize and destroy foreign invaders. It can determine foreign from self and can adapt to virtually destroy any antigen. What happens when the immune system is too efficient for its own good? Allergic immune responses are estimated to effect 20% percent of Americans. The word allergy is defined in the dictionary as a “hypersensitive state.” The hyper-sensitive …showed first 75 words of 3719 total…

…showed last 75 words of 3719 total…by T lymphocytes and macrophages (a type of white blood cell) in the presence of antigens. They cause the T lymphocytes to activate and proliferate. Leukotrienes – Any of a group of hormone derived from arachidonate (arachidonic acid). They are thought to mediate the allergic response that causes lung constriction and muscle contraction in asthma. Urticaria – an allergic reaction in which itchy white lumps surrounded by areas of inflammation appear on the skin; commonly called "hives"