Immunoglobulin E (IgE) Regulation and Biology

immunoglobulin e
Normally present at very low levels in plasma, antibodies of the immunoglobulin E (IgE) isotype were first discovered in 1967, decades after the description of IgA, IgG, and IM. IgE antibodies are produced primarily by plasma cells in mucosal-associated lymphoid tissue and their levels are uniformly elevated in patients suffering from atopic conditions like allergic rhinitis, asthma and atopic dermatitis. Production of allergen-specific IgE in atopic individuals is driven both by a genetic predisposition to the synthesis of this isotype as well as by environmental factors, including chronic allergen exposure. (more…)

Oral Food Challenges & Relationship to Allergen-Specific IgE Levels

Diagnosis of food hypersensitivity is a clinical challenge and the only current definitive test is the Double Blind Placebo-Controlled Food Challenges. Although the Double Blind Placebo-Controlled Food Challenges is the current gold standard, it is difficult to perform and is very time-consuming. Hence, researchers are continually evaluating new tests and assessing the value of the available serum tests. (more…)

SAP Gene Defects In Male Patients Diagnosed With Common Variable Immunodeficiency

The molecular basis of Common Variable Immunodeficiency (CVID) is unknown and the diagnosis requires the exclusion of other diseases known to cause primary antibody deficiency syndromes, such as X-linked lymphoproliferative disease (XLP). XLP is a rare primary immunodeficiency disease in which severe immune dysregulatory phenomena occur, typically after exposure to Epstein–Barr virus (EBV). The defective gene in XLP is SAP (SLAM associated protein, where SLAM is signalling lymphocyte activation molecule), a small SH2 domain containing protein involved in signal transduction events downstream of the SLAM family of receptors. (more…)

Antigen-Specific Cd4 T Cells Drive Airways Smooth Muscle Remodeling In Experimental Asthma

Cd4 T Cells
Airway hyper-responsiveness in asthma may involve smooth muscle growth, a manifestation of airway remodelling. The involvement of inflammatory cells in the induction of airway smooth muscle growth was studied in vivo and ex vivo in a brown Norway rat model of asthma. Transfer of CD4 + T lymphocytes from ovalbuminsensitized animals induced an increase in airway smooth muscle mass in naive animals upon repeated ovalbumin challenge. Ex vivo, coculture of antigen-stimulated CD4 + T cells and airway smooth muscle cells led to myocyte proliferation and prolonged T-cell survival. (more…)

Cow’s Milk Allergy: Immune Response to Protein in Milk

milk allergy

Cow’s milk is the most frequently encountered food allergen in infancy, and milk allergy is often the earliest indicator that a baby is atopic. Precise figures of the incidence of cow’s milk allergy are hard to find because of the difficulties in obtaining an accurate diagnosis, differences in the populations used for research studies, and disagreement about allergy symptoms (clinical criteria) for the condition. All studies agree, however, that cow’s milk allergy is most prevalent in early childhood with an incidence of 2 to 7.5 percent being reported. (more…)

Cow’s Milk Allergy: IgE-Mediated Allergy or Lactose Intolerance?

cow milk allergy

Cow’s milk allergy results when antibodies against milk allergens are produced by the immune system.

Milk allergens are proteins; more than 25 distinct milk proteins have been identified in the various fractions of milk. The fractions include casein, whey, serum, and certain additional ingredients. (more…)

Multiple Antibiotic Allergy Syndrome| Penicilin Allergies

Patients (and many doctors) frequently use the term ‘allergy’ when referring to any adverse drug reaction, even one that has no features of an IgE-mediated allergy response. However, IgE-mediated allergy explains only about 10% of all adverse reactions to antigen antibody reactions from antibiotics. Patients who have experienced unexplained symptoms during treatment with two or more antibiotics are often said to have ‘multiple antibiotic allergy’; using this definition, the description can be applied to one patient in every 22. (more…)

What is Extrinsic Allergic Alveolitis (Hypersensitivity Pneumonitis) ?

Hypersensitivity Pneumonitis
Extrinsic allergic alveolitis (synonym: hypersensitivity pneumonitis) describes an interstitial and bronchioloalveolar disease of the lungs caused by an immune mediated hypersensitivity response. It is associated with repeated exposure to a variety of inhaled organic dusts and reactive chemicals (allergy chemical), but only a proportion of exposed subjects become affected. Notable examples are farmers’ lung (due to actinomycetes contaminating farm produce) and bird fanciers’ lung (due to secreted avian antigens). The disease has considerable potential as a model of allergic lung disease, since the populations at risk can often be identified precisely, the relevant antigens can be purified, and the clinical and immunologic consequences of antigen exposure can be examined. (more…)

Gastrointestinal Allergy Symptoms and Food Intolerance

gastrointestinal allergy symptoms
Gastrointestinal allergy can be classified according to the triggering antigen, the mechanism of immune reaction, or the anatomic site of reaction.

Gastrointestinal allergy may be triggered by food components (e.g. food proteins or glycoproteins), and by other antigen antibody reaction to (e.g. bacterial disease, viral, fungal, and worm antigen), drugs and chemicals, (more…)

Drug Allergy Reaction Classification – Immune Reactions

drug allergy reaction
Drug allergy reactions may be classified, at least theoretically, according to one of four implicated immunologic mechanisms, according to the scheme of Gell and Coombs:

Type I Drug Allergy Reactions

Type I reactions are the result of an IgE antibody reaction, which induces immediate-type hypersensitivity reactions. (more…)

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