title: Evaluation of Eudragit-coated chitosan microparticles as an oral immune delivery system.
abstract: Chitosan microparticles containing ovalbumin (OVA), OVA-containing chitosan microparticles (Chi-OVA), were prepared, coated with Eudragit L100 (ER), and evaluated as oral vaccine. Chi-OVA with an OVA content of 34.4% (w/w) and a mean particle size of 2.3 microm were used for experiments in vitro and in vivo. ER-coated Chi-OVA (ER-Chi-OVA) contained 3.6-20.5% (w/w) OVA and had a particle size of 47.9-161.1 microm. Chi-OVA dissolved readily in JP 14 first fluid, but not in JP 14 second fluid. The release of OVA from Chi-OVA was suppressed extensively in JP 14 second fluid. ER-Chi-OVA did not dissolve in JP 14 first fluid, and the release of OVA was suppressed greatly in JP 14 first and second fluids. OVA solution, Chi-OVA and ER-Chi-OVA (200 and 800 microg OVA/mouse) were administered to Balb/C mice twice at a 1-week interval. At 7 d after the second administration, plasma OVA-specific IgG and fecal OVA-specific IgA levels were measured. OVA-specific IgG tended to be enhanced in Chi-OVA and ER-Chi-OVA, but was the highest in OVA solution. OVA-specific IgA was induced significantly more efficiently by ER-Chi-OVA than the others. These suggested that ER-Chi-OVA should be possibly useful to induce an intestinal mucosal immune response.
authors.affiliation: Department of Drug Delivery Research, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan.
authors.forename: Mika
authors.initials: M
authors.lastname: Hori
authors.forename: Hiraku
authors.initials: H
authors.lastname: Onishi
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Machida
mesh_terms: D000284:Administration, Oral; D000818:Animals; D048271:Chitosan / Q000737:chemistry*; D004355:Drug Stability; D004797:Enzyme-Linked Immunosorbent Assay; D005079:Excipients / Q000737:chemistry*; D005243:Feces / Q000737:chemistry; D005260:Female; D007114:Immunization; D007074:Immunoglobulin G / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010047:Ovalbumin / Q000276:immunology; D011109:Polymethacrylic Acids / Q000737:chemistry*; D012995:Solubility; D014612:Vaccines / Q000008:administration & dosage*
chemical_list: D005079:Excipients; D007074:Immunoglobulin G; D011109:Polymethacrylic Acids; D014612:Vaccines; C038300:methylmethacrylate-methacrylic acid copolymer; D010047:Ovalbumin; D048271:Chitosan