In this study, BD serum-treated macrophages upregulated IL-12 expression and promoted IFNγ+T-bet+ and IL-17A+RORγt+ CD4+T cell differentiation, suggesting that BD serum-induced M1-like macrophages contribute to the inflammation in BD via promotion of Th1 and Th17 differentiation. The gene discussed is IL17A; the disease is Behcet disease.