Tissue kinetics of CD34-TRAIL⁺ cells. Lung, liver, spleen, femur, and tumor were harvested from tumor-bearing NOD/SCID mice 0.5 (■), 5 (□), 24 (green bars), and 48 (red bars) hours after a single intravenous injection of CD34-TRAIL⁺ cells (3 × 10⁶ cells/mouse). (A) Immunohistochemical staining with anti-CD45 antibody was used to detect CD34-TRAIL⁺ cells (arrowheads). Representative images are shown. Objective lens, original magnification: 0.75 NA dry objective, 20×. (B) Quantification of CD34-TRAIL⁺ cells on digitally acquired tissue sections stained with anti-CD45. Mean (± SD) number of CD45⁺ cells per tissue section are shown. At least 3 sections from different animals were analyzed per each tissue.