CSF2 and infection: TheGM-CSF KO model is highly reproducible with the course of infection having threedistinctive phases: phase I/acute defined by a logarithmic CFU increase between days0 and 10 post-challenge; phase II/early chronic consisting of a rapid CFU reductionbetween days 10 and 28 post-infection; and phase III/chronic, characterized by asustained CFU level between days 28 to 90 post-infection.