Figure 2. Human peripheral mononuclear cell arginase I protein expression. Peripheral leukocytes were isolated by density gradient from healthy volunteers (lanes 1–4) and from adult trauma victims 1 day after injury (lanes 5–8). Cell lysates were prepared and arginase I protein expression levels were determined by Western blot analysis (40 μg protein per lane). Samples from four representative controls and four trauma patients are shown. Human liver extract (1 μg) was used as a positive control.