Mannosylated chitosan nanoparticles loaded with FliC antigen as a novel vaccine candidate against Brucella melitensis and Brucella abortus infection.

•We developed subunit vaccine base on FliC antigen for Brucella melitensis and Brucella abortus.•Mannosylated chitosan nanoparticle as an adjuvant significantly induced humoral and cellular immune responses.•Mannosylated chitosan nanoparticle loaded with FliC induced Th1 immunity and conferred protection against Brucellosis.