title: A lipid based multi-compartmental system: Liposomes-in-double emulsion for oral vaccine delivery.
abstract: The gastric mucosa provides the entry point for the majority of pathogens, as well as being the induction site for protective immunity; however, there remain few examples of oral vaccines due to the challenges presented by the gastrointestinal route. In this study, we develop a lipid-based multi-compartmental system for oral vaccine delivery. Specifically, we have optimised the formulation of a water-in-oil-in-water double emulsion prepared from a triglyceride - soya bean oil, using surfactants Span 80/Tween 80 and Pluronic F127 to stabilise the internal and external water phases, respectively. Into the internal water phase, we also incorporated a PEGylated liposome, prepared using hydrogenated phosphatidyl choline as a carrier for our model protein, FITC-labelled ovalbumin. We demonstrated the successful incorporation of intact liposomes into the internal water phase of the double emulsion using imaging techniques including cryo-SEM and confocal microscopy. Finally, we use in vitro release studies of FITC-ovalbumin, to provide further confirmation of the multi-compartmental structure of the double emulsion system and demonstrate significant extended release of the entrapped model antigen compared with PEG-liposomes; these characteristics are attractive for oral vaccine delivery.
authors.affiliation: School of Pharmacy and Medical Sciences, Sansom Institute, University of South Australia, Adelaide, SA 5000, Australia. Electronic address: jin.liau@mymail.unisa.edu.au.
authors.forename: Jin Jau
authors.initials: JJ
authors.lastname: Liau
authors.affiliation: School of Pharmacy, University of Otago, Dunedin, New Zealand. Electronic address: sarah.hook@otago.ac.nz.
authors.forename: Sarah
authors.initials: S
authors.lastname: Hook
authors.affiliation: School of Pharmacy and Medical Sciences, Sansom Institute, University of South Australia, Adelaide, SA 5000, Australia. Electronic address: clive.prestidge@unisa.edu.au.
authors.forename: Clive A
authors.initials: CA
authors.lastname: Prestidge
authors.affiliation: School of Pharmacy and Medical Sciences, Sansom Institute, University of South Australia, Adelaide, SA 5000, Australia. Electronic address: tim.barnes@unisa.edu.au.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Barnes
mesh_terms: D000284:Administration, Oral; D000941:Antigens / Q000008:administration & dosage*; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems; D004655:Emulsions; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D005753:Gastric Mucosa / Q000276:immunology / Q000378:metabolism; D008081:Liposomes; D018613:Microscopy, Confocal / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D010047:Ovalbumin / Q000008:administration & dosage*; D010713:Phosphatidylcholines / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D013024:Soybean Oil / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry; D014612:Vaccines / Q000008:administration & dosage*
chemical_list: D000941:Antigens; D003692:Delayed-Action Preparations; D004655:Emulsions; D008081:Liposomes; D010713:Phosphatidylcholines; D013501:Surface-Active Agents; D014612:Vaccines; D011092:Polyethylene Glycols; D013024:Soybean Oil; D010047:Ovalbumin; D016650:Fluorescein-5-isothiocyanate
keywords: Emulsion; In vitro; Liposome; Multi-compartment; Oral; Vaccine