Immunoglobulin E vaccine(Pfizer)

The challenge to develop new therapeutic strategies to treat asthma is difficult, since drugs such as inhaled steroids and long-acting β2-agonists are very successful and advocated by most national and international guidelines to be the long-term therapies of choice in most of the chronic situations 1. The better understanding of the mechanisms of asthma as an inflammatory disease has led to the development of several new immunological approaches, which have been mostly disappointing after introduction in the clinic. The major reasons for this are linked to the complexity and the redundancy of the inflammatory processes in asthma, which are able to counterpoise the inhibition of a single cellular or molecular pathway 2. Therefore, the global situation for asthma should be increasingly satisfactory based on the currently available treatments, but there are several remaining problems. First, the prevalence and the costs of the disease are still increasing. Secondly, most of the patients deny their asthma symptoms and severity and are mostly under-treated and uncontrolled 3. If mild and moderate asthma can be controlled by the current strategies, poor compliance of the patients still contributes to the excess morbidity and costs. And finally, there is a group of …

An essential requirement for oral vaccines is the ability to survive the harsh environment of the stomach in an antigenically intact form. As bacteriophages are adapted to this environment we used epitope-displaying M13 bacteriophages as carriers for an experimental oral anti-IgE vaccine. The feasibility of this approach was tested in a simulated gastric fluid using two different mimotopes as well as an anti-idiotypic Fab of the non-anaphylactogenic monoclonal anti-IgE antibody BSW17. All phage clones remained infective after this treatment. However, only epitopes displayed on the pVIII protein were still recognized by BSW17 whereas pIII-expressed epitopes were rapidly inactivated. Surprisingly, when used for oral immunization of mice all phage clones induced anti-IgE antibodies. In contrast, oral immunization with the purified, pVIII protein displaying the mimotope induced anti-phage but no anti-IgE antibodies. After feeding a single dose of mimotope-displaying bacteriophage, phage DNA could be detected in mouse feces for 10 days. Our results show that epitope-displaying bacteriophages can be used to induce an epitope-specific antibody response via the oral route.