DEX significantly induced MKP-1 expression in neutrophils from SS asthma patients in a concentration-dependent manner to produce a 6.18 ± 1.46 (P < 0.0001) and 21.38 ± 4.96-fold (P < 0.0001) at 10−6 M and at 10−4 M DEX, respectively,relative to control cells (Fig. 1a). This evidence concerns the gene DUSP1 and asthma.