Chemical Immunology and Allergy

Molecular allergology is a breakthrough science that enables the quantification of IgE antibodies against individual allergen protein components at the molecular level. The diagnosis of IgE-mediated allergic disorders is based on the clinical history and on sensitization demonstrated through an allergy test. Identifying whether the sensitization is primary (species specific) or due to cross-reactivity with proteins with similar protein structures helps the clinician to judge the risk of allergic reaction. This is possible today because allergen component tests for food allergy are now available for clinicians to use in everyday practice...

The diagnosis of food allergy requires responses to two important questions: Does the patient have a food allergy? If so, which foods will elicit allergic symptoms? The first question will most often have to be answered following a physical examination and an interview with the patient and/or caretakers. Based on this, a provisional decision to pursue a food allergy diagnosis may be made after carefully considering other possible reasons for an adverse reaction to a food: aversion, infection, intoxication, or an underlying metabolic disease...

In young children, food allergy is usually acquired via the gastrointestinal tract and directed toward egg and milk. Adolescent and adult patients, however, mainly acquire food allergy via primary sensitization to inhalant allergens on the basis of cross-reactivity between proteins in inhalant sources and in food. This type of food allergy is frequently mediated by sensitization to broadly represented allergens, or so-called panallergens. Food allergic reactions in adult patients - similar to those in children - range in severity from very mild and local symptoms, as in contact urticaria of the oral mucosa, to systemic symptoms involving distal organs, to a fatal outcome...

Food allergy is a potentially life-threatening condition affecting almost 10% of children, with an increasing incidence in the last few decades. It is defined as an immune reaction to food, and its pathogenesis may be IgE mediated, mixed IgE and non-IgE mediated, or non-IgE mediated. Potentially all foods can cause food allergy, but a minority of foods are responsible for the vast majority of reactions reported. A good clinical history is crucial for an accurate diagnosis. Allergy tests, including the skin prick test and measurement of specific IgE antibodies, are useful tools in the case of IgE-mediated or mixed allergy but have not been shown to be of any help in delayed allergic reactions to foods...

Recent studies have suggested that the prevalence of food allergy is increasing in many parts of the world. However, many epidemiology studies have been based only on questionnaires without objective testing. The data from these studies do show that the pattern of food allergies is different across the world. In general, studies using objective testing reported a lower prevalence than those without objective testing. The most common food allergens are cow's milk, hen's egg, wheat, fish, shellfish, peanuts, and tree nuts...

The currently known food allergens are assigned to a relatively small number of protein families. Food allergens grouped into protein families share common functional and structural features that can be attributed to the allergenic potency and potential cross-reactivity of certain proteins. Molecular data, in terms of structural information, biochemical characteristics and clinical relevance for each known allergen, including isoforms and variants, are mainly compiled into four open-access databases. Allergens are designated according to defined criteria by the World Health Organization and the International Union of Immunological Societies Allergen Nomenclature Sub-committee...

Food allergy includes a number of diseases that present with adverse immunological reactions to foods and can be IgE-mediated, non-IgE-mediated, or a combination of both mechanisms. IgE-mediated food allergy involves immediate hypersensitivity through the action of mast cells, whereas non-IgE-mediated food allergy is most commonly cell-mediated. These food allergies are thought to occur as a result of a breakdown in oral tolerance and, more specifically, from an aberrant regulatory T-cell response. Ongoing studies of experimental treatments for food allergy strive to induce oral tolerance and to teach us more about the pathogenesis of food allergy...

Although awareness that food can cause adverse symptoms and even death in some individuals has been present since the times of Hippocrates, it was not until the seminal experiment of Prausnitz that the investigation of food allergy had a more scientific basis. In the first half of the 20th century, there were periodic reports in the medical literature describing various food allergic reactions. Until the studies of Charles May and colleagues in the mid- to late '70s, there was a great deal of skepticism in the medical world about the relevance of food allergy and how to diagnose it, since standard skin testing was known to correlate poorly with clinical symptoms...

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.