Primate Monocytes - CD14, CD16 - Ziegler-Heitbrock

Distinct early cellular kinetics in participants protected from colonization upon Bordetella pertussis challenge.

Abstract

BACKGROUND: To date, only limited data is available on the mechanisms of protection against colonization with Bordetella pertussis in humans. METHODS: In this study, the cellular responses to Bordetella pertussis challenge were monitored longitudinally using high-dimensional EuroFlow-based flow cytometry, allowing quantitative detection of >250 different immune cell subsets in the blood of 15 healthy donors. RESULTS: Participants who were protected against colonization showed different early cellular responses compared to colonized participants. Especially prominent for colonization-protected participants were the early expansion of (CD36-) non classical monocytes at day 1 (d1), Natural Killer cells (d3), follicular T helper cells (d1-d3) and plasma cells (d3). Plasma cell expansion at d3 correlated negatively with the CFU load at d7 and d9 post-challenge. Increased plasma cell maturation at d11-14 was found in participants with seroconversion. CONCLUSION: These early cellular immune responses following experimental infection can now be further characterized and potentially linked to an efficient mucosal immune response, preventing colonization. Ultimately, their presence may be used to evaluate whether new Bordetella pertussis vaccine candidates are protective against Bordetella pertussis colonization, e.g., by bacterial challenge post-vaccination. TRIAL REGISTRATION: NCT03751514. FUNDING: This study is part of the PERISCOPE Project, which has received funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No 115910. The flow cytometric studies were supported by the EuroFlow Consortium.