On the other hand, the Th1 cytokine, TNF-α, is also released during allergic inflammation and may lead to the production of proinflammatory mediators, airway hyperresponsiveness, and remodelling [14], as well as promoting concurrent neutrophil recruitment with the cytokine IL-17A [9], increasing asthma susceptibility and severity [15]. This evidence concerns the gene TNF and asthma.