FOXP3 and Autoimmunity: In addition to orchestrating the molecular signaling of Th17 development, STAT3 may also inhibit Foxp3 transcription via blocking the binding of pSmad3 to a transcriptional enhancer of Foxp3 promoter (33–35), shifting Th17:Treg balance toward Th17 cells and favoring the development of autoimmunity.