Immunity to the respiratory pathogen Bordetella pertussis

Area of Science:

• Immunology
• Vaccinology
• Microbiology

Background:

• Bordetella pertussis causes whooping cough, a significant respiratory infection in all age groups.
• Innate immunity controls early infection, but T-helper type 1 (Th1) and Th17 cells are crucial for bacterial clearance.
• Current acellular pertussis vaccines (aP) show limitations in long-term protection, leading to persistent high incidence.

Purpose of the Study:

• To evaluate the immune responses induced by different pertussis vaccines.
• To identify the immunological correlates of protection against Bordetella pertussis.
• To guide the development of next-generation pertussis vaccines with improved efficacy.

Main Methods:

• Murine models of Bordetella pertussis infection.
• Analysis of innate and adaptive immune cell populations (dendritic cells, macrophages, neutrophils, NK cells, T-helper cells).
• Assessment of immune responses (Th1, Th2, Th17) following vaccination with whole cell pertussis (wP) and acellular pertussis (aP) vaccines.

Main Results:

• Whole cell pertussis vaccines (wP) induce protective immunity largely mediated by Th1 cells.
• Current acellular pertussis vaccines (aP), often alum-adjuvanted, elicit strong antibody, Th2, and Th17 responses but may be less effective.
• Suboptimal, waning, or immune escape phenomena may contribute to the high incidence of pertussis in vaccinated populations.

Conclusions:

• Next-generation acellular pertussis vaccines (aP) should be designed to induce robust Th1 responses for enhanced protection.
• Developing vaccines that promote Th1 immunity is critical to overcome the limitations of current aP and curb the spread of Bordetella pertussis.
• Improved vaccine strategies are necessary to achieve sustained control of whooping cough.