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Allergen AI simulator
(@Allergen_simulator)
Hub AI
Allergen AI simulator
(@Allergen_simulator)
Allergen
An allergen is an otherwise harmless substance that triggers an allergic reaction in sensitive individuals by stimulating an immune response.
In technical terms, an allergen is an antigen that is capable of stimulating a type-I hypersensitivity reaction in atopic individuals through immunoglobulin E (IgE) responses. Most humans mount significant immunoglobulin E responses only as a defense against parasitic infections. However, some individuals may respond to many common environmental antigens. In atopic individuals, non-parasitic antigens stimulate inappropriate IgE production, leading to type I hypersensitivity.[citation needed]
Sensitivities vary widely from one person (or from one animal) to another. A very broad range of substances can be allergens to sensitive individuals.
Allergens can be found in a variety of sources, such as dust mite excretion, pollen, pet dander, or even royal jelly. Food allergies are not as common as food sensitivity, but some foods such as peanuts (a legume), nuts, seafood and shellfish are the cause of serious allergies in many people.
The United States Food and Drug Administration recognizes nine foods as major food allergens: peanuts, tree nuts, eggs, milk, shellfish, fish, wheat, soy, and most recently sesame, as well as sulfites (chemical-based, often found in flavors and colors in foods) at 10ppm and over.[citation needed] In other countries, due to differences in the genetic profiles of their citizens and different levels of exposure to specific foods, the official allergen lists will vary. Canada recognizes all nine of the allergens recognized by the US as well as mustard. The European Union additionally recognizes other gluten-containing cereals as well as celery and lupin.
Another allergen is urushiol, a resin produced by poison ivy and poison oak, which causes the skin rash condition known as urushiol-induced contact dermatitis by changing a skin cell's configuration so that it is no longer recognized by the immune system as part of the body. Various trees and wood products such as paper, cardboard, MDF etc. can also cause mild to severe allergy symptoms through touch or inhalation of sawdust such as asthma and skin rash.
An allergic reaction can be caused by any form of direct contact with the allergen—consuming food or drink one is sensitive to (ingestion), breathing in pollen, perfume or pet dander (inhalation), or brushing a body part against an allergy-causing plant (direct contact). Other common causes of serious allergy are wasp, fire ant and bee stings, penicillin, and latex. An extremely serious form of an allergic reaction is called anaphylaxis. One form of treatment is the administration of sterile epinephrine to the person experiencing anaphylaxis, which suppresses the body's overreaction to the allergen, and allows for the patient to be transported to a medical facility.
Although allergic reactions typically require prior sensitization to a specific allergen, clinical symptoms can sometimes occur upon first exposure to a food or substance; this is explained by IgE cross-reactivity, where prior sensitization to structurally homologous proteins from other sources leads the immune system to recognize similar proteins in the new allergen as triggers, even though the affected individual has never previously consumed or contacted it.
Allergen
An allergen is an otherwise harmless substance that triggers an allergic reaction in sensitive individuals by stimulating an immune response.
In technical terms, an allergen is an antigen that is capable of stimulating a type-I hypersensitivity reaction in atopic individuals through immunoglobulin E (IgE) responses. Most humans mount significant immunoglobulin E responses only as a defense against parasitic infections. However, some individuals may respond to many common environmental antigens. In atopic individuals, non-parasitic antigens stimulate inappropriate IgE production, leading to type I hypersensitivity.[citation needed]
Sensitivities vary widely from one person (or from one animal) to another. A very broad range of substances can be allergens to sensitive individuals.
Allergens can be found in a variety of sources, such as dust mite excretion, pollen, pet dander, or even royal jelly. Food allergies are not as common as food sensitivity, but some foods such as peanuts (a legume), nuts, seafood and shellfish are the cause of serious allergies in many people.
The United States Food and Drug Administration recognizes nine foods as major food allergens: peanuts, tree nuts, eggs, milk, shellfish, fish, wheat, soy, and most recently sesame, as well as sulfites (chemical-based, often found in flavors and colors in foods) at 10ppm and over.[citation needed] In other countries, due to differences in the genetic profiles of their citizens and different levels of exposure to specific foods, the official allergen lists will vary. Canada recognizes all nine of the allergens recognized by the US as well as mustard. The European Union additionally recognizes other gluten-containing cereals as well as celery and lupin.
Another allergen is urushiol, a resin produced by poison ivy and poison oak, which causes the skin rash condition known as urushiol-induced contact dermatitis by changing a skin cell's configuration so that it is no longer recognized by the immune system as part of the body. Various trees and wood products such as paper, cardboard, MDF etc. can also cause mild to severe allergy symptoms through touch or inhalation of sawdust such as asthma and skin rash.
An allergic reaction can be caused by any form of direct contact with the allergen—consuming food or drink one is sensitive to (ingestion), breathing in pollen, perfume or pet dander (inhalation), or brushing a body part against an allergy-causing plant (direct contact). Other common causes of serious allergy are wasp, fire ant and bee stings, penicillin, and latex. An extremely serious form of an allergic reaction is called anaphylaxis. One form of treatment is the administration of sterile epinephrine to the person experiencing anaphylaxis, which suppresses the body's overreaction to the allergen, and allows for the patient to be transported to a medical facility.
Although allergic reactions typically require prior sensitization to a specific allergen, clinical symptoms can sometimes occur upon first exposure to a food or substance; this is explained by IgE cross-reactivity, where prior sensitization to structurally homologous proteins from other sources leads the immune system to recognize similar proteins in the new allergen as triggers, even though the affected individual has never previously consumed or contacted it.