Figure 7.

Sphingosine 1-phosphate receptor (S1PR) agonism reduces the mortality rate in a lethal model of neonatal pertussis infection. Seven-day-old mice were challenged via aerosol with a lethal dose of Bordetella pertussis before receiving either S1PR agonist AAL-R or vehicle intranasally 1 or 72 hours after inoculation. A, Animals receiving vehicle (black line), AAL-R at 1 hour (solid gray line) or 72 hours (dashed gray line) after inoculation were monitored daily for survival. B, On day 6 after inoculation, bacterial burden was assessed from liver and spleen to measure disseminated infection. C, To determine whether AAL-R affected leukocytosis, whole blood was collected on day 6 after inoculation before white blood cell (WBC) counts. Abbreviation: CFUs, colony-forming units.