IL4 and allergic disease: Moreover, low and high doses of AVA both upregulated the Th1 cytokine (IFN-γ) but downregulated the Th2-related cytokines, including IL-4 and IL-13, which indicated that AVA may have regulated the Th1/Th2 imbalance by weakening the Th2 immune response and promoting the Th1 immune response, thereby suppressing the OVA-induced allergic reactions.