The frequency of Th17 cells was positively correlated with the number of unscheduled visits for worsening asthma (r = 0.416, p = 0.020) and the frequency of Th2 cells (r = 0.686, p < 0.001), and was negatively correlated with serum IFN-γ levels (r = −0.615, p = 0.037) (Table 5). Here, IFNG is linked to asthma.