TLR8 and infection: Our data suggest that TLR8 detects RNA-containing Mtb MVs released in response to iron starvation experienced within phagosomes,44 a mechanism that may explain the observed impact of TLR8 on macrophage responses to other bacteria.54–56 It is reasonable to imagine that TLR8 activation may sense viable bacteria (as previously suggested57) that are actively producing RNA-containing MVs since these are likely to be continuously and rapidly cleared or destroyed during in vivo infection.