Author/Authors :
Najafzadeh، Faezeh نويسنده Young Researchers Club, Bonab Branch, Islamic Azad University, Bonab, IR Iran , , Shapouri، Reza نويسنده Department of Microbiology, Zanjan Branch, Islamic Azad University, Zanjan, IR Iran , , Rahnema، Mehdi نويسنده , , Rokhsartalab Azar، Shadi نويسنده Young Researchers and Elite Club, Urmia Branch, Islamic Azad University, Urmia, IR Iran , , Kianmehr، Anvarsadat نويسنده Department of Medical Biotechnology, School of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, IR Iran ,
Abstract :
Background: Treatment of Pseudomonas aeruginosa PAO-1 infections through immunological means has been proved to be efficient and protective.
Objectives: The purpose of this study was to produce a conjugate vaccine composed of detoxified lipopolysaccharide (D-LPS) P. aeruginosa and diphtheria toxoid (DT).
Materials and Methods: Firstly, LPS was purified and characterized from P. aeruginosa PAO1 and then detoxified. D-LPS was covalently coupled to DT as a carrier protein via amidation method with adipic acid dihydrazide (ADH) as a spacer molecule and 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide (EDAC) as a linker. The molar ratio of LPS to DT in the prepared conjugate was 3:1. The immunogenicity of D-LPS-DT conjugate vaccine in mice model was evaluated as well.
Results: The conjugate was devoid of endotoxin activity and 0.125 U/mL of D-LPS was acceptable for immunization. D-LPS-DT conjugate was nonpyrogenic for rabbits and nontoxic for mice. Mice immunization with D-LPS-DT conjugate vaccine elicited the fourfold higher IgG antibody compared to D-LPS. Anti-LPS IgG antibody was predominantly IgG1 subclass and then IgG3, IgG2a and IgG2b, respectively.
Conclusions: Vaccine based on the conjugation of P. aeruginosa PAO-1 LPS with DT increased anti-LPS antibodies and had a significant potential to protect against Pseudomonas infections.
