PTGS2 and asthma: In another miR-155 KO mouse asthma model, it was observed that the lack of miR-155 promotes the reduction in reactive species oxygen (ROS) and cyclooxygenase 2 (COX-2) levels, Th2 and Th17-associated cytokines (IL-4, IL-13, and IL-17) levels in BALF, and in eosinophil infiltration [88]; the expression of miR-155 presented opposite results in the miR-155 KO mouse asthma model (Figure 2b) [88].