Biodegradable Bioadherent Microcapsules for Orally Administered Sustained Release Vaccines

Abstract : This research focuses on the development of an orally administered microencapsulated vaccine against botulinum neurotoxin type A using the non-toxic C-fragment of the neurotoxin (Bot-Ac). The research focuses on the production through recombinant techniques and the incorporation of a known bioadhesive, vitelline protein B (vpb), into the microsphere preparations to enhance uptake of the microspheres by the M cells located in the Peyer's patches. The results demonstrate that vpB can be produced at 170-350 mg/L in a Pichia pastoris expression system. iso, microspheres that contain 10% vpB generate a higher serum IgG level than microspheres that do not contain - B when administered either orally or subcutaneously. Whether vpB is acting as a true bioadhesive is still under study through the use of Peyer's patch uptake experiments. For comparison it was also determined that when 2.0 g of 10 mm microspheres containing 89.9% BSA /10.0% vpB /0.1% Bot-Ac were administered subcutaneously, detectable serum IgG level was generated at 17 weeks post-immunization.