We observed that the level of IL-17a was significantly reduced in the lung tissues of Cd226fl/flCd4-Cre mice and CD226-Fc-treated mice with OVA-induced asthma; however, the level of IL-17a in mediastinal lymph nodes was comparable in Cd226fl/flCd4-Cre (CD226-Fc-treated) and Cd226fl/fl (IgG-treated) mice (data not shown). This evidence concerns the gene IL17A and asthma.