Protective effects of in vivo ‐expressed autotransporters against Bordetella pertussis infection

ABSTRACT Bordetella pertussis causes whooping cough, a severe and prolonged respiratory disease that results in high morbidity and mortality rates, particularly in developing countries. The number of whooping cough cases is increasing in many countries despite high vaccine coverage. Causes for the re‐emergence of the disease include the limited duration of protection conferred by the acellular pertussis vaccines (aP) and pathogenic adaptations that involve antigenic divergence from vaccine strains. Therefore, current vaccines need to be improved. In the present study, we focused on five autotransporters: SphB1, BatB, SphB2, Phg, and Vag8, which were previously found to be expressed by B. bronchiseptica during the course of infection in rats, and examined their protective efficiencies as vaccine antigens. The passenger domains of these proteins were produced in recombinant forms and used as antigens. An intranasal murine challenge assay showed that immunization with a mixture of SphB1 and Vag8 (SV) significantly reduced bacterial load in the lower respiratory tract and combination of aP and SV yield synergistic effects of protection against B. pertussis infection, implying that these antigens have potential as components to improve the currently available acellular pertussis vaccine.
Source: Microbiology and Immunology - Category: Microbiology Authors: Tags: Original Article Source Type: research