Figure 3.

Patterns of bone marrow engraftment recorded in epithelial tissues. In the Fah−/− liver (left hand side), low levels of engraftment are followed by clonal expansion of the bone marrow cells that have fused with host hepatocytes and have been reprogrammed to produce Fah.^11,12,30 In many renewing tissues (right hand side), persistent high levels of engraftment have been recorded, but no clonal expansion is seen, suggesting continued recruitment and loss, with no bone marrow derived cells establishing themselves as stem cells in their new location.^13,26