Analysis of long-term chimerism. (A) Sample dot plot and histogram are shown from dual-color analysis of donor (CD45.1 FITC) peripheral blood chimerism among cells expressing either CD45 isoform (CD45 PE) within the recipients at 6 months of age. (B) Peripheral blood and BM chimerism levels by FACS analysis at 12 months of age in recipients of either congenic or allogeneic marrow.