Protein and DNA nanoparticulate multiantigenic vaccines against H. pylori: in vivo evaluation  Lara Figueiredo 1,2 , Cecília C.R. Calado 2 , António J. Almeida 1 , Lídia M.D. Gonçalves 1 1 Faculdade de Farmácia, Universidade de Lisboa iMed.UL Lisboa, Portugal; (lgoncalves@ff.ul.pt / aalmeida@ff.ul.pt) 2 Faculdade de Engenharia da Universidade Católica Portuguesa, Rio de Mouro, Portugal (c.calado@fe.lisboa.ucp.pt)   Abstract—Immunisation against H. pylori is an attractive option for antibiotic resistance and reinfection situations. Strain genetic heterogeneity, and low immunogenicity of protein antigens and DNA alone are nonetheless obstacles to this approach. We developed multigenic H. pylori DNA-nanoparticle and protein- nanoparticle vaccines based on pathogenic relevance. Six antigens were chosen for the vaccine construction: CagA, VacA, HpaA, UreB, HomB and GroEL. Different combinations of CS/DS and CS/Alg /TPP nanoparticles with DNA and chimeric proteins were produced as vaccine systems. Immune responses were evaluated after i.m. and oral immunisation of BALB/c mice. Oral vaccination successfully stimulated mucosal immunity while i.m. immunisation efficiently elicited a more equilibrated cellular/humoral immune response. Index Terms—nanoparticles; chitosan; vaccine; Helicobacter pylori.   Helicobacter pylori                                      et al         ,           et al    H. pylori                                                                       et al.                            et al                                                                                            A. Protein and DNA chitosan nanoparticle characterization        B. In vivo sudies                                 A. Materials                       B. Animals  in vivo            Authorized licensed use limited to: b-on: Instituto Politecnico de Lisboa. Downloaded on July 30,2020 at 14:59:03 UTC from IEEE Xplore. Restrictions apply.