Koizumi K, et al. - The mechanism underlying infliximab (IFX) in Kawasaki disease (KD) was determine to evaluate the changes in the abundance of CD14⁺CD16⁺ activated monocytes, regulatory T cells (T_reg), and T-helper cell type 17 (Th17) cells following treatment with IFX. It was shown that IFX down-regulates activated monocytes and up-regulates T_reg cells towards the normal range. Therefore, IFX treatment contributes to the process of attenuating inflammation in KD.