title: Biodegradable PLGA microspheres as a delivery system for malaria synthetic peptide SPf66.
abstract: SPf66 is the first chemically synthesised vaccine to elicit a partial protective immune response against malaria. The aluminium hydroxide (alum)-adsorbed SPf66 vaccine is weakly immunogenic and of poor to moderate efficacy in humans. To investigate the possibility of improving SPf66 vaccine immunogenicity, a delivery system based on poly-D,L-lactide-co-glycolide (PLGA) microspheres was developed and the immune response induced after its subcutaneous administration into mice was evaluated. Microspheres were prepared by a solvent extraction/double emulsion (w/o/w) method and characterised for morphology, size, peptide loading, release profile and peptide integrity. The in vitro and in vivo results obtained showed that there was no apparent effect of the encapsulation procedure on SPf66 integrity and immunogenicity. The subcutaneous administration of microspheres showed a significantly higher immune response (serum IgG levels) than that obtained with alum adsorbed SPf66 and it was comparable to that of SPf66 emulsified with Freund's adjuvant (FA). These observations illustrate the potential of PLGA microspheres as a delivery system for chemically synthesised antigens.
authors.affiliation: Pharmacy and Pharmaceutical Technology Laboratory, Pharmacy Faculty, University of the Basque Country (UPV-EHU), Paseo de la Universidad no.7, 01006, Vitoria-Gasteiz, Spain.
authors.forename: J E
authors.initials: JE
authors.lastname: Rosas
authors.forename: R M
authors.initials: RM
authors.lastname: Hernández
authors.forename: A R
authors.initials: AR
authors.lastname: Gascón
authors.forename: M
authors.initials: M
authors.lastname: Igartua
authors.forename: F
authors.initials: F
authors.lastname: Guzman
authors.forename: M E
authors.initials: ME
authors.lastname: Patarroyo
authors.forename: J L
authors.initials: JL
authors.lastname: Pedraz
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004337:Drug Carriers; D016503:Drug Delivery Systems / Q000379:methods*; D005260:Female; D019344:Lactic Acid / Q000276:immunology* / Q000493:pharmacokinetics* / Q000627:therapeutic use; D017780:Malaria Vaccines / Q000008:administration & dosage*; D051379:Mice; D008807:Mice, Inbred BALB C; D008863:Microspheres; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000276:immunology*; D011100:Polyglycolic Acid / Q000493:pharmacokinetics* / Q000627:therapeutic use; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000493:pharmacokinetics* / Q000627:therapeutic use; D015800:Protozoan Proteins / Q000008:administration & dosage* / Q000276:immunology; D011994:Recombinant Proteins; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology / Q000627:therapeutic use
chemical_list: D004337:Drug Carriers; D017780:Malaria Vaccines; D011108:Polymers; D015800:Protozoan Proteins; D011994:Recombinant Proteins; C066269:SPf66 protein, Plasmodium; D014614:Vaccines, Synthetic; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid