Though in a murine model of TB, the protective role of GM-CSF producing non-myeloid cells, such as iNKT and CD4 T cells has also been reported during MTB infection which suggests that perhaps these cells could also be contributing to maintain an optimum level of GM-CSF required for the effective functioning of macrophages (Figure 2) (11, 22). The gene discussed is CD4; the disease is tuberculosis.