Nevertheless, immune-modulating asthma therapies now undergoing clinical trial, such as those targeting IL-4, IL-13, chemokines, antibody receptors, PPAR-γ, or Toll-Like Receptors, are expected to alter the functions of macrophages even though it remains unclear what role macrophages play in the pathogenesis of asthma [7]. This evidence concerns the gene IL4 and asthma.