TLR4 and infection: To identify the sequential order of the pathways involved in the TLR4-dependent pathway, we explored the transcriptional patterns of genes related to TLR signaling in WT and Tlr4-/- BMDCs infected with L. infantum. In vitro infection of DCs induces a slight upregulation of transcript expression, reinforcing the idea that L. infantum can silently survive inside DCs [16,17].