title: Release kinetics and immunogenicity of parvovirus microencapsulated in PLA/PLGA microspheres.
abstract: The aim of this work was to examine the immunogenicity of microencapsulated inactivated duck parvovirus in Muscovy duck (Cairina moschata) and goose. Inactivated duck parvovirus suspension was microencapsulated into 14-17 kDa poly(lactide) (PLA) and poly(lactide-co-glycolide) (PLGA50:50H) by coacervation. The in vitro antigen release from individual and mixed PLA and PLGA50:50H microspheres (MS) was biphasic with an initial lag-phase of approx. 10 days followed by a relatively constant release over additional 12 days. By varying the composition of PLA+PLGA50:50H MS mixtures from 3+1 to 1+3, the release kinetics could be altered and controlled efficiently. The antigen-loaded MS were injected subcutaneously into ducks. The immune response, expressed as virus neutralisation (VN) titres, after single administration of MS was modest, i.e. below 200 over the 6 weeks tested, unless the animals were pre-immunised 3 weeks before injecting the MS. The weak immune response was attributed to the low dose injected and inappropriate antigen release kinetics. With pre-immunised animals, however, the results were encouraging and showed that the encapsulated parvovirus was immunogenic.
authors.affiliation: Ceva-Phylaxia Veterinary Biologicals Company, Szállás utca 5, Budapest, 1107, Hungary.
authors.forename: E
authors.initials: E
authors.lastname: Pálinkó-Biró
authors.forename: G
authors.initials: G
authors.lastname: Rónaszèki
authors.forename: H P
authors.initials: HP
authors.lastname: Merkle
authors.forename: B
authors.initials: B
authors.lastname: Gander
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000008:administration & dosage*; D001672:Biocompatible Materials; D004339:Drug Compounding / Q000379:methods*; D004372:Ducks; D004797:Enzyme-Linked Immunosorbent Assay; D007700:Kinetics; D019344:Lactic Acid; D008863:Microspheres; D009500:Neutralization Tests; D017992:Parvovirus / Q000276:immunology*; D011091:Polyesters; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers
chemical_list: D000956:Antigens, Viral; D001672:Biocompatible Materials; D011091:Polyesters; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; C033616:poly(lactide)