IL6 and infection: Indeed, quantification of cytokine production by ELISA revealed a spike in secretion 6 hours post- infection with a doubling in TNF alpha levels and a fivefold increase in IL-6 levels (IL-6 average 90 pg/mL, TNFα 40 pg/mL) that were already back to baseline levels 1 day after infection (Fig. 5A).