Infused bone marrow cells do not incorporate into the regenerating liver vasculature. (A) Experimental outline of PHx-induced liver regeneration in NSG mice. Prior to the angiogenic phase (on day 2 after PHx), mice were infused intravenously with YFP-labeled bone marrow cells as a regenerative cellular therapy. (B) The frequency of YFP⁺ hematopoietic cells (CD45⁺) in the liver and the peripheral blood of sham-operated and PHx mice was analyzed by FACS (mean ± SD, n = 4–5 mice). (C) The ratio of YFP⁺ ECs in the livers of sham-operated and PHx mice was analyzed by FACS (mean ± SD, n = 4–5 mice). (D) Representative images of liver sections of sham-operated and PHx mice costained with YFP, CD45, and liver EC–specific marker (Lyve-1/Col-IV). Zoomed-in images are shown at the bottom. Arrows indicate YFP⁺ cells. All traced YFP⁺ cells were positive for CD45 but negative for EC markers. Scale bars, 25 µm. (E) Shown are the absolute numbers of YFP⁺ cells, YFP⁺ hematopoietic cells, and YFP⁺ ECs counted per 1 mm² of the liver tissue of sham-operated and PHx mice (mean ± SD, n = 4–5 mice). Two-tailed Student’s t test.