Caetano, Liliana AranhaFigueiredo, LaraAlmeida, António J.Gonçalves, L. M.2018-01-172018-01-172017-04Caetano LA, Figueiredo L, Almeida AJ, Gonçalves LM. BCG-loaded chitosan microparticles: interaction with macrophages and preliminary in vivo studies. J Microencapsul. 2017;24(2):203-17.http://hdl.handle.net/10400.21/7928The 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 immunization 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 the intranasal route. These positive results indicate that the proposed approach of whole live BCG microencapsulation in chitosan-alginate for intranasal immunization was successful in allowing efficient interaction with APC while improving the cellular immune response, which is of interest for local immunization against tuberculosis.engAdministration, IntranasalAnimalsAntibodies, BacterialBCG VaccineChitosanFemaleHumansImmunoglobulin AImmunoglobulin GMacrophagesMiceMice, Inbred BALB CMycobacterium bovisTHP-1 Cellsjournal article10.1080/02652048.2017.1316325