Biological Standardization of Allergen Extracts of Pollens of Betula Pendula, Phleum Pratense and Mite Extract of Dermatophagoides Pteronyssinus

2014-08-27 03:12:48 | BioPortfolio


Allergen extracts are complex mixtures of proteins and contain varying amounts of allergenic and non-allergenic components. Many factors such as the biovariability, differences in extraction process and subsequent handling of allergens can affect the final composition, potency, and stability of allergen preparations. Genetic diversity of affected people adds another level of complexity. In order to control variability and to achieve consistency and reproducibility for optimal safety and sensitivity/specificity, it is essential to standardize the amount of allergen used in prick tests. Therefore, the system for biological standardization mainly used in Europe still is the biological calibration of in-House Reference Preparations (IHRP). The method has been adopted by the Nordic Council on Medicines as the Nordic Biological Unit, Histamine Equivalent Potency (HEP) or Skin Prick Test (SPT) value. The aim of this procedure is to estimate the biological activity of allergen extracts. The activity of an allergen extract is defined as 10,000 Diagnostic Biological Units (DBU) per ml (1 SPT per ml), when the extract provokes a specific skin reaction with a wheal of the same size as a wheal provoked by reference histamine at a concentration of 10 mg/ml, when both solutions are administrated using the same technique (prick testing) on at least 20 individuals who are clinically allergic and cutaneously reactive to the allergen concerned.

The present study aims to standardize the allergen extracts of Betula pendula, Phleum pratense and Dermatophagoides pteronyssinus by using this method.

- Trial with medicinal product

Study Design

Allocation: Non-Randomized, Control: Active Control, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic




Extracts of allergens




Not yet recruiting


University of Zurich

Results (where available)

View Results


Published on BioPortfolio: 2014-08-27T03:12:48-0400

Clinical Trials [341 Associated Clinical Trials listed on BioPortfolio]

Comparing Allergenic Effects of 3 German Cockroach Extracts in Adults

The purpose of this study is to test and compare the allergenic effects of three commercially available German cockroach allergen extracts in adults. Study hypothesis: The biological pote...

Allergy Immunotherapy for the Reduction of Asthma

In this clinical study we aim to determine the effect of allergy immunotherapy in decreasing asthma and allergy related disease in children who had multiple episodes of wheezing and who ar...

Potential Allergens in Wine: Double-Blind Placebo-Controlled Trial

This study is designed to identify whether wines which are produced using the common potential food allergens such as proteins derived from fish, milk or egg are likely to contain sufficie...

The Effect of Autologous Autovaccine in Patients With Allergy on House-Dust-Mite

House dust mite allergy is a common problem, resulting in asthma, chronic swelling of the eyes, and running nose. We test a possibility to immunize subjects sensitized against house dust m...

The Diagnosis of Oral Allergy Syndrome Through the Use of a Structured Questionnaire

Oral allergy syndrome is a type of food allergy which mainly affects people with springtime hay fever. It is caused by a cross-reaction, between antibodies to pollens, usually birch tree p...

PubMed Articles [2019 Associated PubMed Articles listed on BioPortfolio]

Allergen content in German cockroach extracts and sensitization profiles to a new expanded set of cockroach allergens determine in vitro extract potency for IgE reactivity.

Cockroach allergens are an important cause of IgE-mediated sensitization in inner-city asthmatics. However, cockroach extracts used for diagnosis and immunotherapy are not standardized.

Detection of genuine grass pollen sensitization in children by skin testing with a recombinant grass pollen hybrid.

Skin testing represents a commonly used first diagnostic method in clinical practice but allergen extracts may vary in composition and often contain cross-reactive allergens and therefore do not alway...

Peanut allergy - individual molecules as a key to precision medicine.

Peanut allergy is one of the most severe food allergies affecting millions of individuals worldwide. In German-speaking countries, peanut allergy is the most important cause of anaphylaxis in children...

Bedroom Exposure to Airborne Allergens in the Chicago Area Using a Patient-Operated Sampling Device.

In current practice, allergens in vacuum collected dust are used as surrogates for inhalable allergens. We developed an airsampling device that can be used by patients themselves for direct measuremen...

Mapping of conformational IgE epitopes of food allergens.

Food allergies reduce the quality of life of affected individuals and may result in anaphylaxis or even death. Allergen-specific immunotherapy (AIT) is based on vaccination with the disease-causing al...

Medical and Biotech [MESH] Definitions

A method of treating an ALLERGY by administering ALLERGENS, in liquid formulation or tablets, to the ORAL MUCOSA under the tongue.

Antigens from the house dust mites (DERMATOPHAGOIDES), mainly D. farinae and D. pteronyssinus. They are proteins, found in mite feces or mite extracts, that can cause ASTHMA and other allergic diseases such as perennial rhinitis (RHINITIS, ALLERGIC, PERENNIAL) and atopic dermatitis (DERMATITIS, ATOPIC). More than 11 groups of Dermatophagoides ALLERGENS have been defined. Group I allergens, such as Der f I and Der p I from the above two species, are among the strongest mite immunogens in humans.

An in vitro allergen radioimmunoassay in which allergens are coupled to an immunosorbent. The coupled allergens bind the IgE in the sera of patients which in turn binds radioisotope-labeled anti-IMMUNOGLOBULIN E antibodies.

Plant extracts from several species, including genera STRYCHNOS and Chondodendron, which contain TETRAHYDROISOQUINOLINES that produce PARALYSIS of skeletal muscle. These extracts are toxic and must be used with the administration of artificial respiration.

Historically, the treatment of disease by the administration of animal organs or their extracts (after Brown-Sequard). At present synthetic preparations substitute for the extracts of a gland. (From Stedman, 26th ed)

More From BioPortfolio on "Biological Standardization of Allergen Extracts of Pollens of Betula Pendula, Phleum Pratense and Mite Extract of Dermatophagoides Pteronyssinus"

Quick Search


Relevant Topics

Biological Therapy
Biological therapy involves the use of living organisms, substances derived from living organisms, or laboratory-produced versions of such substances to treat disease. Some biological therapies for cancer use vaccines or bacteria to stimulate the body&rs...

Wound management
Anything that breaks the skin is a wound because when the skin is broken, there's a risk of germs getting into the body and causing an infection. Follow and track Wound Care News on BioPortfolio: Wound Car...

Acne Dermatology Eczema Psoriasis Wound Care Dermatology is the medical specialty concerned with the diagnosis and treatment of skin disorders (Oxford Medical Dictionary). As well as studying how the skin works, dermatology covers...

Searches Linking to this Trial