Adoptive Regulatory T-cell Therapy Attenuates Perihematomal Inflammation in a Mouse Model of Experimental Intracerebral Hemorrhage

The CD4(+)CD25(+) regulatory T cells (Tregs), an innate immunomodulator, suppress cerebral inflammation and maintain immune homeostasis in multiple central nervous system injury, but its role in intracerebral hemorrhage (ICH) has not been fully characterized. This study investigated the effect of Tregs on brain injury using the mouse ICH model, which is established by autologous blood infusion. The results showed that tail intravenous injection of Tregs significantly reduced brain water content and Evans blue dye extravasation of perihematoma at day (1, 3 and 7), and improved short- and long-term neurological deficits following ICH in mouse model. Tregs treatment reduced the content of pro-inflammatory cytokines interleukin (IL)-1 beta, IL-6, tumor necrosis factor-alpha, and malondialdehyde, while increasing the superoxide dismutase (SOD) enzymatic activity at day (1, 3 and 7) following ICH. Furthermore, Tregs treatment obviously reduced the number of NF-kappa B+, IL-6(+), TUNEL+ and active caspase-3(+) cells at day 3 after ICH. These results indicate that adoptive transfer of Tregs may provide neuroprotection following ICH in mouse models.