Increase in T helper type 17 cells in children with Kawasaki disease is NR4A2 dependent

The aim of this study was to evaluate the relationship between T helper type 17 (Th17) cells and Kawasaki disease (KD). Flow cytometry results showed that the number of Th17 cells in the peripheral blood mononuclear cells (PBMCs) of KD patients was significantly elevated. Enzyme-linked immunosorbent assay (ELISA) results showed that the serum concentrations of two Th17 cytokines, interleukin (IL)-17 and IL-6, were significantly increased in KD patients. In addition, real-time quantitative polymerase chain reaction (PCR) results showed that the messenger RNA (mRNA) expression of two molecules related to Th17 cell differentiation, retinoic acid–related orphan receptor C (RORC) and NR4A2, was upregulated in the CD4+ T cells of KD patients. Intravenous immunoglobulin (IVIG) infusion significantly reduced the proportion of Th17 cells, decreased serum concentrations of IL-7 and IL-6, and lowered the mRNA levels of RORC and NR4A2 in IVIG treatment–sensitive KD patients. Finally, the results of a Pearson’s correl...