Production of multilamellar, small unilamellar and reverse-phase liposomes containing house dust mite allergens. Potential adjuvants in the immunotherapy of allergic disease.
The capacity of multilamellar (MLV), small unilamellar (SUV) and reverse-phase vesicle (REV) liposomes to incorporate house dust mite allergens has been studied. All three liposome preparations entrapped mite proteins with efficiencies of 36% (SUV), 29% (MLV) and 14% (REV). MLV incorporated the complete range of proteins contained in mite extracts with apparent molecular weights ranging from 14,000 to greater than 67,000 as judged by sodium dodecyl sulphate polyacrylamide gel electrophoresis. However, several proteins with apparent molecular weights (MW) of 16,000, 36,000 and 43,000 were excluded from the REV and SUV. Immunoblotting analysis using a serum pool prepared from mite allergic individuals showed that whereas the whole spectrum of allergens was incorporated into the MLV, a MW 43,000 allergen was excluded from the REV and SUV. The exclusion of these mite components is probably a function of the relatively prolonged exposure of the original extract to organic solvent in the preparation of the REV and SUV liposomes.