Allergen VLPs

Abstract

The use of antigenic VLPs has recently impacted the vaccine industry by allowing the development of efficacious, safe and low cost recombinant vaccines. We are currently investigating the potency of allergens presented in the form of recombinant VLPs for immunotherapy. Transient expression of a fusion protein made of a natural non-immunogenic carrier peptide fused to an allergen component was used to produce VLP particles harboring spikes of either homotrimers or homotetramers of a major dust mite allergen. These VLPs were purified and characterized in preparation for a head-to-head mouse efficacy study in comparison with the same allergen in a soluble form and whole dust mite commercial extracts. VLPs were readily formed with both trimeric and tetrameric forms of the the antigen. Their purification was performed with a succession of simple filtration and ion-exchange chromatography steps. The particles were between 130 and 180 nm in diameter, harboring an average of 900 spikes of the homopolymers on their surface. Their membrane was made of lipids typical of membrane rafts. Their production showed high reproducibility both in yield and quality. They are currently under efficacy trial in mice. This combination of a new manufacturing technology and a new 3D antigen display technology is GMP compliant, low cost and has unlimited capacity. Its functionality has now been tested with some of the major allergens. This new technology has the power to bridge the gap between the rapidly increasing knowledge of the immunological basis of allergy and the manufacturing of therapeutic allergens.