TFF2 and infection: Through disrupted barrier, apically located Sp can translocate to reach the blood vessel (Beisswenger et al., 2007) (Figures 1Ac,Bc), where they are either killed by resident immune cells that circulate in the blood (Li et al., 2002; Li, 2004), or grow uncontrollably and result in invasive infection if the immune cells cannot contain the translocated Sp (Silverstein and Rabadan, 2012).