Over-Expression and Immunogenicity of Outer Membrane Protein L (OprL) of Pseudomonas aeruginosa

Pseudomonas aeruginosa is a notorious pathogen that causes opportunistic infections in humans and animals. Despite high number of patients who may develop P. aeruginosa infections and the threat of antibiotic treatment failure due to fast development of antimicrobial resistance, surprisingly no vaccine is currently available in the market against the bacterium. The present study is aimed to produce recombinant outer membrane protein L (rOprL) of P. aeruginosa using suitable prokaryotic expression system and to evaluate its immunogenicity in experimental animals so that it can be considered as a vaccine candidate in future. OprL was successfully expressed and purified as ~19 kDa protein. Immunization of mice with rOprL resulted in increased antigen specific serum antibody titer and protected the mice against P. aeruginosa challenge. This preliminary study suggests that OprL may prove to be a potential subunit vaccine candidate against P. aeruginosa infections.