Protective efficacy of aTyphimurium ghost vaccine candidate constructed with a recombinant lysozyme-PMAP36 fusion protein in a murine model.

Abstract

ATyphimurium ghost vaccine was constructed with the use of a recombinant fusion protein consisting of lysozyme and porcine myeloid antimicrobial peptide 36 expressed by theoverexpression system. After confirmation of its effectiveness by transmission electron microscopy the vaccine was evaluated in a murine model. Of the 60 BALB/c mice equally divided into 4 groups, group A mice were intramuscularly inoculated with 100 μL of sterile phosphate-buffered saline, and the mice in groups B, C, and D were intramuscularly inoculated with approximately 1.0 × 10, 1.0 × 10, or 1.0 × 10cells of theTyphimurium ghost vaccine, respectively, in 100-μL amounts. The serum IgG titers againstTyphimurium outer membrane proteins were significantly higher in groups B to D than in group A, as were the concentrations of interleukin-10 and interferon gamma in supernatants of harvested splenocytes. After challenge with wild-typeTyphimurium, all the vaccinated groups showed significant protection compared with group A, notably perfect protection in groups C and D. Overall, these results show that intramuscular vaccination with 1.0 × 10cells of this ghost vaccine candidate provided efficient protection against systemic infection with virulentTyphimurium.