Circadian Signaling Affects T Cell Responses to Vaccination

Vaccination is one of the most effective tools avail­able against infectious dis­ease. Nonetheless, opti­mizing vaccine efficacy remains a top priority for scientists, especially to better protect high-risk populations. The time of day at which a vaccine is delivered affects response robustness, but how this occurs from a cellular and molecular level is not well understood.^1-3 A recent publication in Nature Communications from Annie Curtis’s research group at the Royal Col­lege of Surgeons in Ireland linked circa­dian shifts in dendritic cell (DC) func­tion with oscillations in mitochondrial morphology and metabolism.⁴ Moreover, Curtis’s team showed that these mecha­nisms can be directly modulated using small molecule agents—a potentially useful future approach for enhancing vaccine responses.

Most, if not all, biological functions in humans are affected by the circadian clock—stable oscillations in gene expres­sion across a 24-hour cycle regulated by a set of conserved, self-sustaining tran­scriptional-translational feedback loops.1 Scientists have found that circadian rhythms ...