PLGA Nano-particles Containing Brucella abortus Omp19 Induced Potent Protective Immunity in Mouse Model

Prevention of the globally spread zoonotic infection, brucellosis which affects an extensive range of hosts including humans and animals is still challenging researchers. There are no approved vaccines for prevention of human disease and those used for animal brucellosis have adverse properties which limit their application. Here we investigated the immunological and protective effects of PLGA nano-particles containing recombinant 19kDa outer membrane protein of Brucella abortus (Omp19) which introduced a new candidate for brucellosis subunit vaccine. Brucella Omp19 was expressed and produced in PET-PAa(+) and in E coli BLT1(DEM) system. Recombinant Omp/9 (rOmp19) was purified using nickel resin. Female BALB/c mice were immunized with rOmp19 and Nano-rOmp 19; afterwards specific serum antibodies were evaluated. Production of IL-IT, IL-and IFN-y from mice spelenic lymphocytes were also measured in cell culture. Protection of immunized mice against pathogenic B. abortus aff was also evaluated by intraperitoneal bacterial challenge. Recombinant Omp19 was successfully produced with a significant purity. Significant total serum IgG along with remarkable IgG) and IgGľa response to rOmp19 was recorded. High levels of significant IL-1 and IFN-y was induced in mice which were immunized with Nano-rOmp 19. Intraperitoneal challenge with B. abortus aff confirmed that Nano-rOmp19 is able to elicit efficient protective immune responses in animal host. According to significant cell-mediated immune responses elicited by the PLGA nano-particles which were loaded with rOmp 19, this antigen and delivery system can be used as an efficient vaccine candidate in further Brucella vaccine investigations.

Keywords:

Brucella , vaccine , PLGA , Omp19 , brucellosis