We collected supernatants of mPEOs at 0, 2, 4, 8, and 24 h after USA300 infection and measured IL-1β expression levels of 0 ± 0, 982.00 ± 108.55, 2562.62 ± 172.03, 2621.46 ± 137.35 and 1315.83 ± 86.14 pg/mL respectively by ELISA (Fig. 5E). Here, IL1B is linked to infection.