However, consistent with the observation that the mature CCV does not co-localize with endocytic tracers, the lysosomal marker cathepsin B was seen in only a very small proportion of the CCVs, even at 2 h after infection (Figure 5H and Figure S4), although it was present in 95% of vacuoles containing S. tyhimurium invA (invasin) (Figure 5G and Figure S4). Here, CTSB is linked to infection.