CTSE and infection: Downregulation of BNIP3 and CTSE expression by specific siRNAs in the late infection phase (Additional file 4: Figure S4B), which is a phase normally characterized by high protein levels of BNIP3 and CTSE (Fig. 8a and b), resulted in a significant increase in the infection rates at 48 h p.i. compared to the rate of L. m.-infected control BMDM transfected with negative control siRNA at the same time point (Fig. 8c).