Indeed, GM-CSF levels are increased in both bronchoalveolar lavage fluid (BAL) and lungs 24 h after LPS exposure (1 μg LPS i.t. or i.n.; Fig. 1A,B), as expected25, and in the lungs 1 month post M. tuberculosis infection in WT mice, although this was transient and essentially no GM-CSF was detected 3 months post-infection (Fig. 1C). The gene discussed is CSF2; the disease is infection.