In our experiments, pre-treatment of PEM with either cytochalasin D, an inhibitor of actin polymerization and thus internalization, dynasore, an inhibitor of the endocytic effector dynamin, or chloroquine, which inhibits endosome acidification [30], [31], significantly impaired the induction of IFN-β following Listeria infection, strongly suggesting that phagocytosis of L. monocytogenes and intracellular location of TLR2 trigger this response. This evidence concerns the gene IFNB1 and listeriosis.