Overall there was a clear hierarchical trend of WT > ΔcspAD (CspB) > ΔcspAB (CspD) > ΔcspBD (CspA) > ΔcspABD (Figure 1A; P < 0.05) observed with respect to the intracellular bacteria CFU levels reached inside the THP-1 macrophages at 6 and 24 h post infection (Figure 1A). Here, GZMB is linked to infection.