Arbeiten aus dem Paul-Ehrlich-Institut (Bundesinstitut fur Impfstoffe und biomedizinische Arzneimittel) Langen/Hessen最新文献

In Japan, standardization of allergens for therapeutics and diagnosis is very limited. Only one allergen (Cryptomeria japonica) extract was standardized. The standardization of two kinds of allergens for therapeutics (Cedar pollen and Dermatophagoides allergens) is now progressing. As for food allergens, the Japanese Ministry of Health Labour and Welfare (MHLW) made a decision for mandatory labeling of foods containing allergenic ingredients in 2001. Egg, milk, wheat, buckwheat and peanut, and most recently shrimp and crab require mandatory labeling. Standardization of food allergens for allergenic ingredient measurement has been advanced.

A variety of positive outcomes can be realized from validation and risk management activities (see Table 4). They are dependent on the participation of multiple functional groups including the quality unit, regulatory and legal affairs, engineering and production operations, research and development, and sales and marketing. Quality risk management is receiving increased attention in the area of public health, pharmacovigilance, and pharmaceutical manufacturing. Recent examples of its regulatory use in our industry include the assessment of the potential risks of transmissible spongiform encephalopathies (TSE) agents through contaminated products], the risks of precipitates in allergenic extracts, and the revision of the potency limits for standardized dust mite and grass allergen vaccines. Its application to allergen source material process validation activities allowed for a practical strategy, especially in a complex manufacturing environment involving hundreds of products with multiple intended uses. In addition, the use of tools such as FMEA was useful in evaluating proposed changes made to manufacturing procedures and product specifications, new regulatory actions, and customer feedback or complaints. The success of such a quality assurance programs will ultimately be reflected in the elimination or reduction of product failures, improvement in the detection and prediction of potential product failures, and increased confidence in product quality.

The new concept of immunotherapy with IVN201 against cat dander allergy combines two proprietary technology platforms: Intralymphatic immunotherapy (ILIT) with Modular-Antigen-Transportation (MAT) proteins. Intralymphatic immunotherapy (ILIT) is the injection of immunotherapeutics directly into the lymph node. Lymph nodes contain a high density of antigen presenting cells together with interacting T cells, which are necessary for allergen tolerance development. Therefore, this site-directed route of administration requires fewer injections of much smaller doses of the allergen than conventional administration routes to induce a highly effective, disease modifying immune response. ILIT was recently demonstrated in a clinical study to enhance safety and efficacy of immunotherapy and to reduce treatment time from 3 years to 8 weeks with only three injections, thereby significantly improving patient compliance. Patients subjectively perceived the intralymphatic injections less painful than a venous puncture. IVN201 is a functional fusion peptide which is a tailor-made recombinant allergen for ILIT with Fel d 1 as allergen module. It is designed to be rapidly taken up by antigen presenting cells in the lymph nodes and to improve the presentation of the allergen to the immune system. IVN201 was shown to induce allergen tolerance in a murine anaphylaxis model. Stimulation assays with basophil leukocytes isolated from allergic patients suggest an increased safety profile when compared to cat extract or recombinant Fel d 1. Therefore, MAT molecules are expected to be safer and more efficacious in inducing the desired immune response than recombinant allergens or allergen extracts in allergen immunotherapy when administered via the intralymphatic route.

Allergens are embedded into the protein universe as members of large families and superfamilies of related proteins which is a direct consequence of their shared evolution. The classification of allergens by protein families offers a valuable frame of reference that allows the design of experiments to study cross-reactivity and allergenic potency of proteins. Information on protein family membership also complements the current official IUIS allergen nomenclature. All presently known allergens belong to one of 140 (1.4%) of the 10,340 protein families currently described by version 23.0 of the Pfam database. This is indicative of a strong bias among allergens towards certain protein architectures that are able to induce an IgE response in an atopic immune system. However, even small variations in the structure of a protein alter its immunological characteristics. Various isoforms of the major birch pollen allergen Bet v 1 were shown to possess highly variant immunogenic and allergenic properties. Ber e 1 and SFA8, two 2S albumins, were revealed to display differential capacities to polarise an immune response. Such data will be exploited in the future for the design of allergy vaccines.

Allergen specific immunotherapy has traditionally been viewed as a treatment for established atopic disease. The disease target of choice has principally been allergic rhinitis, and in contrast there has been widespread reluctance in sectors of the clinical community to extend this approach to treatment of atopic asthma. However as understanding of the underlying pathogenic mechanisms which drive asthma aetiology and pathogenesis increases, the rationales for considering immunotherapy in this treatment context are expanding, particularly in relation to primary and secondary prevention of asthma in childhood. This brief review highlights recent development relating to this issue.