Pulmonary delivery of GM-CSF 2 to 4 weeks prior to infection significantly reduced mortality in S. pneumoniae infected mice, and this increased survival was accompanied by an increase in the expression of inducible nitric oxide synthase and antibacterial activity in lung sentinel cells, as well as a significant decrease in caspase-3-dependent apoptosis and secondary necrosis. This evidence concerns the gene CSF2 and infection.