In addition, another study demonstrated that adoptive transfer of IL-10-producing B cells into the stroke mice could increase the expression of PD-1 in peripheral CD4+ T-cells (Bodhankar et al., 2013a), suggesting that PD-1/PD-L1 interaction might also be important in regulatory B cell-provided neuroprotection after stroke (Ren et al., 2011a; Bodhankar et al., 2013a). Here, CD4 is linked to stroke disorder.