FOXP3 and stroke disorder: To further analyze the location of Treg in the ischemic brain during the early phase of stroke, we performed immunohistochemistry of brain specimen taking advantage of genetically modified mice, in which Foxp3-expressing cells are visible by a transgenic construct linking green fluoresecent protein and the DTX receptor (DEREG mice).4,11 We could show that Treg were predominantly located within the vessel lumina (Figure 2E) and did not transmigrate into the brain parenchyma until day 1 after stroke, which is in line with previous studies.1,4