Furthermore, RA inhibits the expression of the master regulator transcription factor of Th1 cells, that is, T‐bet, and induces the transcription factors promoting Th2 cells, such as GATA‐binding protein 3 (GATA3), macrophage‐activating factor (MAF), and signal transducer and activator of transcription 6 (STAT6) [29, 62]. Here, STAT6 is linked to rheumatoid arthritis.