It has been previously shown in a murine asthma model that the suppression of allergic airway disease correlates with an increase of IL‐10+CD4+ cells.48, 49 In addition, Phl p‐5‐restimulated splenocytes from mice treated with TGFβ1‐mim showed reduced levels of secreted IFN‐γ, IL‐2, IL‐4, IL‐5, and IL‐13 cytokines, which act in concert to determine T helper polarization.10 Here, CD4 is linked to asthma.