title: BCG-loaded chitosan microparticles: interaction with macrophages and preliminary in vivo studies.
abstract: The aim of this study was to develop a novel BCG-loaded chitosan vaccine with high association efficiency which can afford efficient interaction with APC and elicit local and Th1-type-specific immune response after intranasal administration. Chitosan-suspended BCG and BCG-loaded chitosan-alginate microparticles were prepared by ionotropic gelation. Interaction with APC was evaluated by fluorescence microscopy using rBCG-GFP. Specific immune responses were evaluated following intranasal immunisation of mice. Cellular uptake was approximately two-fold higher for chitosan-suspended BCG. A single dose of BCG-loaded microparticles or chitosan-suspended BCG by intranasal route improved Th1-type response compared with subcutaneous BCG. Chitosan-suspended BCG originated the highest mucosal response in the lungs by intranasal route. These positive results indicate that the proposed approach of whole live BCG microencapsulation in chitosan-alginate for intranasal immunisation was successful in allowing efficient interaction with APC, while improving the cellular immune response, which is of interest for local immunisation against tuberculosis.
authors.affiliation: a Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy , University of Lisbon , Lisbon , Portugal.|b Department of Ciências e Tecnologias Laboratoriais e Saúde Comunitária, ESTeSL - Escola Superior de Tecnologia da Saúde de Lisboa , Instituto Politécnico de Lisboa , Lisbon , Portugal.
authors.forename: Liliana Aranha
authors.identifier: http://orcid.org/0000-0003-1496-2609
authors.initials: LA
authors.lastname: Caetano
authors.affiliation: a Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy , University of Lisbon , Lisbon , Portugal.
authors.forename: Lara
authors.initials: L
authors.lastname: Figueiredo
authors.affiliation: a Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy , University of Lisbon , Lisbon , Portugal.
authors.forename: António J
authors.initials: AJ
authors.lastname: Almeida
authors.affiliation: a Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy , University of Lisbon , Lisbon , Portugal.
authors.forename: L M D
authors.initials: LMD
authors.lastname: Gonçalves
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001500:BCG Vaccine / Q000008:administration & dosage / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000097:blood; D008264:Macrophages / Q000187:drug effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D009163:Mycobacterium bovis; D000074084:THP-1 Cells
chemical_list: D000907:Antibodies, Bacterial; D001500:BCG Vaccine; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D048271:Chitosan
keywords: BCG vaccine; chitosan; microencapsulation; mucosal vaccination