Further, treatment with recombinant GM-CSF (rGM-CSF) prior to mycobacterial infection enhanced intracellular killing and phagolysosomal fusion after Mtb infection as well as intracellular mycobacterial killing and superoxide anion release after Mycobacterium avium complex (MAC) infection (125, 129). Here, CSF2 is linked to Mycobacterium infection.