CD34 ⁺ bone marrow cells do not contribute to liver fibrosis or ICC. (A) Schematic of bone marrow transplantation followed by biliary fibrosis or ICC induction. (B) Confocal image showing Tomato expression in a subset of CD45⁺ immune cells in the liver from wild-type mice that had been transplanted with bone marrow cells from Cd34^creER;R26^tdTomato mice. Arrowheads depict the Tomato⁺CD45⁺ cells. Scale bar = 50 µm (n = 5 mice from three independent experiments). (C and D) Confocal images showing no contribution of Tomato⁺ cells to Col1⁺ cells in the liver from DDC-treated (C) or ICC-bearing (D) wild-type recipients that had been transplanted with bone marrow cells from Cd34^creER;R26^tdTomato mice. Scale bar = 200 µm (n = 5 mice from three independent experiments). (E) Schematic of transplantation of wild-type bone marrow cells into Cd34^creER;R26^tdTomato, Cd34^creER;R26^DTA, and R26^DTA recipient mice. (F) Confocal image showing no Tomato expression in CD45⁺ immune cells in the liver from Cd34^creER;R26^tdTomato recipients. Scale bar = 50 µm (n = 5 mice from three independent experiments). (G and H) Anti-Sox9 staining of paraffin liver sections (G) from R26^DTA and Cd34^creER;R26^DTA recipients. The numbers of Sox9⁺ cholangiocytes forming the circumference of the bile ducts were quantified (H). Scale bar = 100 µm (n = 5 mice per genotype from three independent experiments). (I and J) H&E staining of paraffin liver sections (I) from ICC-bearing R26^DTA and Cd34^creER;R26^DTA recipients. The percentage of tumor area within liver sections was quantified (J). Scale bar = 200 µm (n = 5 mice per genotype from three independent experiments).