Mouse Infection Assay with PTX3

Mouse infection assays were performed as previously reported [29 (link)]. Mice were intraperitoneally injected with HA9801 3 × 10⁸ CFU/mouse with or without PTX3 (5 μg, 10 μg and 20 μg, respectively). Every 2 h, three infected mice were sacrificed by cervical dislocation and their blood, lungs and livers were harvested, weighed and homogenized in PBS. Subsequently, the homogenates and bloods were serially 10-fold diluted and plated on THA medium to enumerate CFU. At the same time, the cytokine IL-6 in the blood of infected mice was detected by specific ELISAs (BD Pharmingen and R&D Systems).