The immune system serves as the body's defense mechanism against the countless different substances present in the air we breathe, the foods we eat, and particles our skin get into contact with. Allergens refers to any substance that can trigger an allergic response. Common allergens in the air include pollen, mold, animal dander, house dust mite, cockroaches, among others.
Antibodies are substances produced by the body for neutralization, engulfment, and destruction of pathogens. People who have allergies have an antibody called Immunoglobulin E, called IgE. This is produced as a result of genetic and environmental interaction. Upon encountering the offending allergen, these antibodies bind those particles viewing them as harmful. They travel to cells called mast cells, which are particularly plentiful in the nose, eyes, lungs and gastrointestinal tract. Here, these antibodies bind and activate mast cells resulting in release of chemical “mediators” such as histamine and other chemicals.
These mediators produce the symptoms of an allergic reaction, such as swelling of tissues, sneezing, wheezing, coughing, urticaria and other reactions.
Each type of IgE is specific for one type of allergen only. That's why some people are only allergic to cat dander (they only have the IgE antibodies specific to cat dander) and others seem to be allergic to other.
This event occur each time the immune system is encountered with the incremented allergen/s.
MECHANISMS OF ALLERGIC DISEASES
