Single cell transcriptomics correlate avian coronavirus prime vaccination efficacy with antigen-presenting cell...

Area of Science:

• Veterinary Immunology
• Coronaviruses
• Vaccine Development

Background:

• Avian infectious bronchitis virus (IBV) poses a significant threat to poultry health, necessitating improved vaccine strategies.
• Decades of vaccination have not fully controlled IBV, highlighting gaps in understanding prime vaccination responses.
• Rational vaccine design requires a deeper insight into the initial immune interactions following immunization.

Purpose of the Study:

• To elucidate the in vivo immune dynamics following prime vaccination with live-attenuated and inactivated IBV vaccines in chickens.
• To compare the mechanisms by which different vaccine types shape adaptive immune cell populations and responses.
• To identify key factors, such as antigen-presenting cell (APC) preference, that correlate with vaccine effectiveness.

Main Methods:

• Construction of dynamic, single-cell resolution blood immune landscapes in chickens post-vaccination.
• Bioinformatic analysis of immune cell populations and T-cell receptor (TCR) repertoires.
• In vivo assessment of lymphocyte activation, APC utilization, and antibody production.

Main Results:

• Both live-attenuated and inactivated IBV vaccines induced distinct immune cell compositions through different mechanisms.
• Inactivated vaccines relied on dendritic cells, while live-attenuated vaccines initially preferred monocytes/macrophages as APCs.
• APC preference, rather than vaccine type, correlated with vaccine effectiveness, as seen in avian influenza vaccination.

Conclusions:

• Prime vaccination strategies significantly influence the subsequent adaptive immune response.
• Antigen-presenting cell preference is a critical determinant of vaccine efficacy for avian coronaviruses.
• This research provides a comprehensive characterization of avian coronavirus prime vaccination, guiding future vaccine design.