CD4 and stroke disorder: Recent studies have reported that CD4+ Tregs play a protective role against damage following stroke (Liesz et al., 2009; Planas and Chamorro, 2009; Li et al., 2013), while others demonstrate Tregs as harmful promoters of neurodegeneration (Kleinschnitz et al., 2013a; Kleinschnitz and Wiendl, 2013b) or find that Tregs do not influence stroke (Ren et al., 2011; Gu et al., 2012; Stubbe et al., 2013).