Studies were performed using 6-to 8-week-old male CD1 mice (Jackson Laboratory, Bar Harbor, ME), which were housed in pathogen-free conditions at the University of Illinois animal care facility. Experimental sepsis was induced via CLP performed as previously described. 13 In brief, after proper sterilization, the cecum was exposed via a midline abdominal incision and ligated at 75% of the distance between the distant cecal pole and the base of the cecum, followed by a 21-gauge needle puncture in a mesenteric toward antimesenteric direction. Wound closure was achieved using separate sutures (6-0 nylon) to the abdominal musculature and the skin. Immediately after the procedure, 500 L of warmed normal saline solution was administered subcutaneously. For survival studies, the mice were monitored every 6 hours for 24 hours, and thereafter every 12 hours for 5 days. All cell injections were administered 1 hour after CLP via i.v. administration through the facial vein. Studies were performed in accordance with institutional guidelines, and approval was obtained from the institutional review board.