The use of poly(D,L-lactic-co-glycolic) acid microspheres in the treatment of allergic disease

Abstract

This article reviews literature on the use of poly(D,L-lactic-co-glycolic) acid (PLGA) microspheres for the treatment of IgE-mediated hypersensitivity. The discussion will focus on the encapsulation and release of proteins from microspheres, the interaction of microspheres with the immune system through different routes of delivery, and the therapeutic changes that are noted following this form of allergy immunotherapy. Allergenic proteins which are encapsulated into PLGA microspheres are able to be recognized by the immune system. When placed into the body via injection or ingestion, the proteins are slowly released from the microspheres over an extended period of time, producing a shift in the immune system away from an allergy-dominant pattern. This has been shown to cause an improvement in symptoms, a decrease in medication use and protection against developing severe allergic reactions. Because of the slow release of protein from the microspheres over time, less frequent treatments are necessary compared with conventional immunotherapy, resulting in a more convenient treatment. Because regular bolus injections are avoided, a steadier level of protein is delivered to the body, and this may result in a safer, as well as more effective, form of immunotherapy.