ARG1 and ischemia: Consistent with histological results, we detected a dramatic upregulation of Arg1 mRNA levels in focal areas after ischemia induction, and the Arg1 levels significantly dropped after MCLs treatment (from 77.73 ± 0.81 in the stroke-MLs group to 25.80 ± 1.67 in the stroke-MCLs group) (Figure 4A).