Allergy and Clinical Immunology

Immune System and Allergic Reactions

Immune system involves antibodies, white blood cells, mast cells, proteins and other substances fight against antigens (foreign substances). However, in susceptible people, the immune system can exaggerate when exposed to certain substances like allergens in the environment, foods, or drugs, which are not harmful in most people. The result is an allergic reaction. Allergic reactions are hyperactive responses of the immune system to generally non-toxic substances. When immune cells act against the allergenic protein, IgE antibodies are generated; this is homogenous to the immune system's reaction to foreign pathogens. The IgE antibodies recognize the allergenic proteins as harmful and instigate the allergic reaction. Severe allergic reactions results in following symptoms: