title: Novel chitosan particles and chitosan-coated emulsions inducing immune response via intranasal vaccine delivery.
abstract: OBJECTIVE
  The aim of this study was to prepare a novel vaccine carrier particulate system (nanoparticles and emulsions) with chitosan and to evaluate the effect of this system on the immune response for intranasal delivery.
  
  
  METHODS
  Chitosan nanoparticles (NP) and chitosan-coated emulsions (CC-Emul) were prepared by improvement of the method previously reported and by modified ethanol injection methods, respectively. The rats were immunized with the particles adsorbed with ovalbumin (OVA) and cholera toxin (CT) by intranasal (i.n.) and intraperitoneal (i.p.) administration.
  
  
  RESULTS
  NP and CC-Emul could be prepared with particle diameter from about 0.4 microm to 3 microm. IgG induced by i.n. of NP was comparable with that by i.p., and IgA induced by i.n. of 0.4-microm- and 1-microm-size NP was significantly higher than control (OVA and CT). IgG and IgA induced by i.n. of 2-microm-size CC-Emul were significantly higher than those with control.
  
  
  CONCLUSIONS
  The novel chitosan particles used simple preparation methods showed high OVA adsorption. When administered intranasally, NP and CC-Emul induced systemic immune response in rats. These findings suggested that CC-Emul and the smaller-size (0.4 microm) NP are effective for targeting to nasal-associated lymphoid tissues (NALTs) in nasal vaccine delivery.
authors.affiliation: Institute of Medicinal Chemistry, Hoshi University, Ebara 2-4-41, Shinagawa, Tokyo 142-8501, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nagamoto
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Hattori
authors.forename: Kozo
authors.initials: K
authors.lastname: Takayama
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Maitani
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D048271:Chitosan / Q000008:administration & dosage*; D016503:Drug Delivery Systems / Q000379:methods*; D004655:Emulsions; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D036103:Nanotechnology / Q000379:methods*; D051381:Rats; D011921:Rats, Inbred WKY; D014612:Vaccines / Q000008:administration & dosage* / Q000276:immunology*
chemical_list: D004655:Emulsions; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D014612:Vaccines; D048271:Chitosan