PTX3 and infection: As shown in Figs 1C and S1A, PTX3 opsonization with only the concentration of 50 μg/mL significantly decreased the number of intracellular bacteria at 1 h and 2 h post-infection (p.i.)(p< 0.001: PTX3-opsonized M90T vs. M90T plus BSA at 2h) to levels like those induced by the anti-IpaD antibody.