IL4 and asthma: It promotes antitumor immunity via activations of natural killer cells and Th1 T cells.[11] A recent study has demonstrated that IL-12, an important cytokine secreted by T lymphocyte, may play an important role in the pathogenesis of asthma.[12] Therefore, based on previous studies, this study is aimed to analyze the correlations between the levels of IL-4, IL-6, and IL-12 and lung function, cellular immune function, and QOL in children with moderate-to-severe asthma.