Listeria monocytogenes induces the expression of retinoic acid-inducible gene-I.

Retinoic acid-inducible gene-I (RIG-I) is considered to play a role in innate immunity against virus infections. We showed by immunohistochemical study that RIG-I expression is upregulated in vivo in hepatic Kupffer cells and in splenic reticular cells of mice infected with Listeria monocytogenes. Both heat-killed L. monocytogenes and live L. monocytogenes induced the expression of RIG-I in cultured RAW264.7 murine macrophage-like cells in vitro. RIG-I may also be involved in innate immunity against Listeria infection.