KLF2 and KLF4 are transcription factors that have been shown to directly regulate endothelial function and integrity in vascular endothelium and to protect against endothelial dysfunction, both in vitro and in murine models, and their expression is modulated by both changes in laminar sheer flow or stress and pro-inflammatory stimuli (44, –, 49). The gene discussed is KLF4; the disease is endothelial dysfunction.