Characterizing Donor-Derived Cells in Nonhematopoietic Tissue Aravind Ramakrishnan, Daqing Shi, Beverly Torok-Storb  Biology of Blood and Marrow Transplantation  Volume 12, Issue 9, Pages 990-992 (September 2006) DOI: 10.1016/j.bbmt.2006.05.003 Copyright © 2006 American Society for Blood and Marrow Transplantation Terms and Conditions

Figure 1 Liver and intestinal sections from a female patient who received an allogeneic stem cell transplantation from a male donor. Combined immunohistochemistry for the CD45 antigen and FISH for sex chromatin were performed on each section. (A) A section of liver stained with CD45. (B) A photomicrograph of a combined fluorescence and standard light exposure of the same section to simultaneously reveal FISH for the Y chromosome (green signal) and immunostaining for CD45 (black precipitate). (C) FISH for sex chromatin (X in red; Y in green) in an intestinal section from the same patient. (D) Combined standard light microscopy and fluorescence showing immunostaining for CD45. All cells that have a Y signal are positive for CD45, indicating that these cells are in the hematopoietic lineage. Biology of Blood and Marrow Transplantation 2006 12, 990-992DOI: (10.1016/j.bbmt.2006.05.003) Copyright © 2006 American Society for Blood and Marrow Transplantation Terms and Conditions

Figure 2 Combined immunohistochemistry for the CD45 antigen and FISH for sex chromatin from a liver section from the same patient. (A) Two cells in the field have Y signals (green). One of these cells is CD45 positive, as shown on the overlay image in (B) (thin arrow); the other cell has 2 X signals (red) and 1 Y signal and represents a fusion event (thick arrow). Some cells have only 1 X signal or no FISH signal, due to sectioning through different planes. Biology of Blood and Marrow Transplantation 2006 12, 990-992DOI: (10.1016/j.bbmt.2006.05.003) Copyright © 2006 American Society for Blood and Marrow Transplantation Terms and Conditions