Regulation of T helper cell subsets by cyclooxygenases and their metabolites

► Prostanoids influence cytokine production on both antigen presenting cells and T cells to regulate the differentiation of naïve CD4+ T cells to Th1, Th2 and Th17 cell phenotypes. ► COXs and PGE2 generally suppressing Th1 differentiation and exacerbate Th2 and Th17 phenotypes. ► Targeting of cyclooxygenases and their eicosanoid products may represent a new approach for treatment of inflammatory diseases, tumors and autoimmune disorders.