Allergy and Pollen
The understanding of allergy is growing exponentially with the ongoing expansion in our knowledge of the immune system. The immune system is the capacity to distinguish harmful non-self molecules from self-molecules, a characteristic that exists in a deli
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Allergy and Pollen
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What Is Allergy?
The understanding of allergy is growing exponentially with the ongoing expansion in our knowledge of the immune system. The immune system is the capacity to distinguish harmful non-self molecules from self-molecules, a characteristic that exists in a delicate balance between tolerance to self and response or rejection of non-self. This system is focused on host defense and is composed of specific cellular and protein components that develop and function in a highly complex manner, in order to neutralize or destroy dangerous non-self while preserving self. Allergic responses are clear examples of the detrimental side of the immune system, because they represent immunological reactions to innocuous environmental elements, resulting in annoying and sometimes debilitating effects in the affected individuals. The allergic response involves hypersensitivity reactions directed at allergens, in contrast to similar hypersensitivity mechanisms that provide host protection to parasitic infections. Autoimmunity defines a state in which tolerance to self is lost and the immune response is activated against host tissues. Otherwise, allergic and hypersensitivity reactions are the result of immune responses to innocuous non-self molecules. Allergy is a kind of disorders in which this balance is disrupted, which is an abnormal reaction to a very small amount of a specific substance, called an allergen which is usually proteins or
glycoproteins of a molecular weight of 10,000– 60,000 Da. This substance is harmless to general people who do not have this particular allergy. Allergens stimulate the production of allergic antibodies or of sensitized cells. This response is mediated by immunoglobulin (Ig) E antibody specific to the allergen. Mast cells and basophils are activated after IgE binding, starting a series of cellular and molecular events that results in the clinical manifestations of allergic disease. Allergens usually contained in pollens, molds, animal skin cells, danders, or hairs, house dust, insects, medication, or even foods such as milk, eggs, soy, wheat or nuts, fish, shellfish. These allergens cause trouble when they are inhaled, or swallowed, or injected into the body [1]. Allergic sensitization can be arisen de novo at any stage of life. However it is much more common for these diseases to appear initially in a mild form during childhood. Indeed, particularly in the case of allergy, the transient appearance of IgE against ubiquitous environmental allergens in early childhood is so frequent within the overall population that it can be classed as normal and it is only in a small subset of children that these responses fail to resolve spontaneously and instead persist and consolidate, leading to clinically significant allergic symptoms. It is also becoming increasingly evident that this period in early life represents a crucial window period of opportunity for modulation of these responses before they become persistent. There is accordingly interest
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