title: Cellulose acetate phthalate microparticles containing Vibrio cholerae: steps toward an oral cholera vaccine.
abstract: Oral cholera vaccine (OCV) has been recommended in some endemic areas and epidemic situations since 1999. Although safe and effective vaccines are currently on the market, the burden of transport and storage remains an issue. Herein, we report an approach to develop an alternative OCV in the form of a gastro-resistant powder. Heat-killed Vibrio cholerae (VC) was encapsulated with a spray-drying technique at different temperatures. Cellulose acetate phthalate (Aquacoat® CPD) was chosen as the core polymer and the addition of alginate was studied. The microparticles (MPs) produced were characterized by surface morphology, particle size, drug loading, antigenicity and gastro resistance. The MPs obtained were 6 µm in size and had appropriate drug content, ranging from 8.16 to 8.64%. Furthermore, antigenicity was maintained, never dropping below 85%, and enteric properties were achieved for all the formulations. Next, an in vivo study was carried out with Aquacoat® CPD MP prepared at 80 °C with and without alginate. Two different doses were assayed, 30 and 60 mg, and compared to the VC suspension. The evoked immune responses showed that alginate containing MPs, especially at the 30 mg dose, displayed values that were very similar to those of VC. In conclusion, spray-dried alginate VC MPs seem to be a promising step toward a powder-form cholera vaccination.
authors.affiliation: NanoBioCel Group, Laboratory of Pharmaceutics, University of the Basque Country, School of Pharmacy , Vitoria-Gasteiz , Spain .
authors.forename: Marta
authors.initials: M
authors.lastname: Pastor
authors.forename: Amaia
authors.initials: A
authors.lastname: Esquisabel
authors.forename: Iratxe
authors.initials: I
authors.lastname: Marquínez
authors.forename: Arturo
authors.initials: A
authors.lastname: Talavera
authors.forename: José Luis
authors.initials: JL
authors.lastname: Pedraz
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002482:Cellulose / Q000031:analogs & derivatives* / Q000737:chemistry; D022121:Cholera Vaccines / Q000008:administration & dosage*; D005260:Female; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D051381:Rats; D017207:Rats, Sprague-Dawley; D013499:Surface Properties; D014734:Vibrio cholerae
chemical_list: D022121:Cholera Vaccines; D002482:Cellulose; C011708:cellulose acetate phthalate
keywords: Cellulose acetate phthalate; cholera vaccines; enteric microparticles; spray drying