CSF2 and asthma: The median (IQR) GM-CSF cells/mm2 of submucosa was increased in severe asthma (1.4 (3.0)) compared with those with mild to moderate asthma (0 (2.5)) and healthy controls (0 (0.5)), (p = 0.004, Kruskal–Wallis; between-group comparisons are as shown fig 3A).