Editorial [Hot Topic: New Targets for Prevention and Treatment of Allergies (Guest Editor: Udo Herz)]

The incidence and prevalence of allergic diseases such as asthma, has increased dramatically over the last decades with major socioeconomic consequences. Although enormous efforts have been undertaken to understand the underlying pathomechanism in more detail, asthma is still one of the diseases for which only limited curative therapies are available. As a consequence, identification of appropriate recommendations for prophylaxis and risk management is important. This issue aims to provide an overview on the current state of therapy of asthma and new developments for the prevention of this disease. The first article provides a conceptional point of view on how allergen exposure during early childhood including the prenatal period might trigger the onset of allergy and asthma later in life (Herz et al.). The paper of Strid and Strobel deals with processes of primary sensitization to allergens and provides recent information supporting that epidermal allergen exposure may contribute to systemic allergic sensitization. An overview on the pharmaceutical treatment of asthma in children is given in the article by Carlsen, addressing non-pharmacological and pharmacological aspects of treating allergic airways. Over the last years, a new promising therapeutic agent to treat asthma has been developed. It is well established that there is a close association between IgE antibodies and asthma symptoms. IgE exert their pro-inflammatory effects by binding to receptors expressed on a variety of cell types including mast cells, basophils and antigen presenting cells. Removing IgE from the continuing cycle of allergic inflammation can be considered as an unique anti-inflammatory mode of action of humanized anti-IgE antibodies. Hamelmann et al. summarize the current facts about action, safety and efficacy of anti-IgE therapy. The second part of the issue is targeted on discussions of new developments for therapy and prevention of asthma, starting with two articles providing further insights into antigen processing, presentation and T-cell tolerance induction in the intestinal mucosa. Any antigen/allergen gets in contact with the body defense system through the mucosal immune system present along the respiratory, gastrointestinal and genitourinary tract. Recent data indicate that these first steps are determinative of the later onset of diseases or the development of tolerance. Doganci et al. describe the processes of mucosal immune regulation and the role of transcription factors as possible new therapeutic targets. The article by Wiedermann assesses the potential benefit of recombinant allergens or allergen constructs in combination with mucosal antigen delivery systems, such as lactic acid bacteria in the prophylaxis and therapy of allergy. Another promising approach to induce an anti-allergic immune response in the body is the use of bacterial DNA. The DNA vaccine technique has opened a vast scope of novel approaches for protective and therapeutic treatments of allergies. The article by Weiss et al. presents an overview on the current status of allergy DNA vaccines and present advances in the design of vaccine constructs. The issue is closed by an overview from Björksten on the evidence of probiotics in prevention of allergy and asthma. The intestinal flora is likely to be particularly important in orchestrating host immune responses and thereby affecting the risks of allergy. This has led to several studies of probiotics as therapeutic modulators of inflammatory responses.