Investigation of the Outer Membrane Vesicles of Bordetella pertussis

Introduction and Objective: Bordetella pertussis is the causative agent of whooping cough, a highly contagious respiratory disease most severe in infants and young children. Notably, the resurgence of pertussis has been mostly attributed to waning vaccine-induced immunity, the switch from whole cell vaccines to acellular vaccines (aP) and pathogen adaptation in theface of the selection pressure induced by the vaccine that results in changes in the B. pertussis bacterial population strains that do not have a perfect match with the vaccine.The epidemiological situation of pertussis points out the need to develop new generation of vaccines that capable of conferring both long-lasting immunity and protection against different strain genotype in this regard we characterize the properties of OMVs obtained from Bordetella pertussisas a good vaccine candidate. Material and Methods:The isolate of B. pertussiswas grown at 36 ◦C for 72 h on Bordet Gengou agar (BGA) supplemented with 10% defibrinated sheep blood, and subcultured 24 h in the same medium before use.The OMVs obtained fromBordetella pertussis strain were negatively stained and examined with an electron microscope.SDS-PAGE, immunoblot techniques were used to describe OMVs properties. Results:The size range of OMV was consistent from batch to batch and similar to previously described OMV preparations.To further characterize the OMVs,immunoblottings were performed using specific antibodies against Ptx and Prn and Fha.OMVs studiesexpressed all three main protective immunogen. Conclusion:According to the results,OMVs derived from B. pertussis express 3 virulence factors, it is tempting to speculate that protective efficacy observed with all OMVs may be attributed to common factors that are expressed in all bacterial strains used. sinceOMVs reported here contain main immunogens used in currently acellular vaccines but expressed in the context of the pertussis membrane, allowing the immune response to preferentially target surface-exposed epitopes in their native conformation, it might be considered asa possible basic material for the development of acellular pertussis vaccines.