Donor HSCs engraft in the liver and spleen in microinjected embryos and larvae to create stable chimeras. (A) Anesthetized larva 1 month after microinjection transplant with the liver visible through the skin (white box). (B) Anesthetized 3-month-old larvae 4 days after microinjection transplant with the spleen visible through the skin (white box). (C-D) In vivo GFP channel view of the magnified liver in A and spleen in B shows engraftment of a large number of GFP⁺ donor cells. (E-F) H&E staining (×40) of the liver and spleen from a 2-year-old microinjected chimera. (G) Section (×40) displaying donor GFP⁺ cell engraftment in the liver in E. No preference for the peripheral hematopoietic layer is visible. (H) Section (×40) displaying greater donor GFP⁺ cell engraftment in the spleen in F than in the liver.