CSF2 and infection: In contrast to murine bone marrow-derived macrophages (BMDMs) differentiated with macrophage-colony stimulating factor (M-CSF), bone marrow-derived dendritic cells (BMDCs) differentiated with granulocyte macrophage-colony stimulating factor (GM-CSF) are not permissive for intracellular Legionella replication as they undergo rapid mitochondrial apoptosis during infection (68, 69).