Correspondence
Chimerism of the Transplanted Heart
N Engl J Med 2002; 346:1410-1412May 2, 2002
- Article
To the Editor:
Quaini and colleagues (Jan. 3 issue)1 claim that stem cells of host origin are found in transplanted hearts. The authors identified host-derived cells within the transplanted organs on the basis of the detection of Y chromosomes in male recipients of female hearts. To establish the stem-cell nature of these cells, they used immunohistochemical studies to evaluate the expression of three molecules (c-kit, MDR1, and Sca-1) that have previously been used to identify hematopoietic stem cells in mice (Sca-1 and c-kit) and humans (MDR1 and c-kit).2-4 As the authors indicate, none of these three molecules are unique to hematopoietic stem cells; at present, only functional studies in combination with multidimensional flow cytometric analysis to evaluate the presence or absence of at least four antigens can suggest the identity of these cells.5 Furthermore, the use of the Sca-1 reagent in the current study is particularly troublesome, since the antibody used by the investigators is specific for mouse cells and is not cross-reactive with human bone marrow cells (unpublished data). Thus, the authors have inadvertently provided an example of rather high background levels of nonspecific antibody staining. This not only negates their conclusion that Sca-1 cells are present but also calls into question all their immunohistochemical findings. Quaini et al. have used inappropriate methods to reach an inappropriate conclusion and, in so doing, have added confusion to an emerging area of research already mired in controversy.
5 ReferencesGerald J. Spangrude, Ph.D.
University of Utah, Salt Lake City, UT 84132
drblood@path.utah. edu Beverly Torok-Storb, Ph.D.
Marie-Terese Little, Ph.D.
Fred Hutchinson Cancer Research Center, Seattle, WA 981091
Quaini F ,Urbanek K ,Beltrami AP , et al. Chimerism of the transplanted heart. N Engl J Med 2002;346:5-15
Full Text | Web of Science | Medline2
Spangrude GJ ,Heimfeld S ,Weissman IL . Purification and characterization of mouse hematopoietic stem cells. Science 1988;241:58-62[Erratum, Science 1989;244:1030.]
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Chaudhary PM ,Roninson IB . Expression and activity of P-glycoprotein, a multidrug efflux pump, in human hematopoietic stem cells. Cell 1991;66:85-94
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Broudy VC ,Lin N ,Zsebo KM , et al. Isolation and characterization of a monoclonal antibody that recognizes the human c-kit receptor. Blood 1992;79:338-346
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Baum CM ,Weissman IL ,Tsukamoto AS ,Buckle AM ,Peault B . Isolation of a candidate human hematopoietic stem-cell population. Proc Natl Acad Sci U S A 1992;89:2804-2808
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To the Editor:
Quaini et al. conclude that chimerism is caused by the migration of primitive cells from the male recipient to the female grafted heart. Unfortunately, the authors failed to consider other potential causes of chimerism, including that associated with transfusion, pregnancy, or both.
Quaini et al. provide no information about the reproductive history of the donors (and female controls). Had the donors previously given birth to male children? Fetal CD34+CD38+ stem cells persist in the peripheral blood in healthy women for as long as 27 years after delivery.1 Fetal-cell microchimerism also develops after elective termination of pregnancy.2 According to a recent report, a section of a thyroid adenoma removed from an otherwise healthy woman was entirely male, whereas the remaining thyroid tissue was entirely female.3 The presence of male cells has been reported in the heart of a woman with two sons who died of complications of lupus and had no history of transfusions.4 Thus, there is strong evidence that fetal cells can migrate to the heart and that, at least in the thyroid, they can differentiate into mature tissue.
The genetic origin of the chimeric cells could be distinguished by micromanipulating the male cells out of the donor heart, amplifying highly polymorphic DNA sequences within them, and comparing the sequences to DNA from both the recipient and the donor's son. Until there is DNA-based confirmation, it is premature to assume that the chimeric cells were derived from the recipient.
4 ReferencesDiana W. Bianchi, M.D.
Kirby L. Johnson, Ph.D.
Deeb Salem, M.D.
New England Medical Center, Boston, MA 02111
dbianchi@lifespan.org 1
Bianchi DW ,Zickwolf GK ,Weil GJ ,Sylvester S ,DeMaria MA . Male fetal progenitor cells persist in maternal blood for as long as 27 years postpartum. Proc Natl Acad Sci U S A 1996;93:705-708
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Bianchi DW ,Farina A ,Weber W , et al. Significant fetal-maternal hemorrhage occurs after termination of pregnancy: implications for development of fetal cell microchimerism. Am J Obstet Gynecol 2001;184:703-706
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Srivatsa B ,Srivatsa S ,Johnson KL ,Samura O ,Lee SL ,Bianchi DW . Microchimerism of presumed fetal origin in thyroid specimens from women: a case-control study. Lancet 2001;358:2034-2038
CrossRef | Web of Science | Medline4
Johnson KL ,McAlindon TE ,Mulcahy E ,Bianchi DW . Microchimerism in a female patient with systemic lupus erythematosus. Arthritis Rheum 2001;44:2107-2111
CrossRef | Web of Science | Medline
To the Editor:
Quaini et al. suggest that cardiac chimerism observed in heart-transplant recipients may be due to the migration of undifferentiated progenitor cells. In support of this hypothesis, the authors report increased numbers of cells expressing c-kit, MDR1, and Sca-1 in transplanted human hearts. However, it should be noted that c-kit is expressed in human mast and endothelial cells,1 and MDR1 is expressed in a wide range of human cell populations, including endothelial cells.2 Sca-1 (Ly-6A/E), a phosphatidylinositol-anchored protein, is expressed on some hematopoietic stem cells in mice with both Ly-6 haplotypes. This antigen is murine and is not known to be a human progenitor-cell marker. In any case, there are reports of Sca-1 expression in murine heart vasculature.3 Thus, the immunohistochemical images in the report by Quaini et al. do not rule out the possibility that endothelial cells account for the increased number of cells that were positive for c-kit and MDR1 in the transplanted hearts. In fact, increased numbers of male hepatic venous endothelial cells have been reported in liver-biopsy samples from men who had received liver grafts from female donors.4 With regard to Sca-1, data on specificity should be provided in order to clarify what human cells are indicated by the monoclonal antibody used in the study.
4 ReferencesFrancesco Bertolini, M.D., Ph.D.
Giancarlo Pruneri, M.D.
European Institute of Oncology, 20141 Milan, Italy
francesco.bertolini@ieo. it 1
Konig A ,Corbacioglu S ,Ballmaier M ,Welte K . Downregulation of c-kit expression in human endothelial cells by inflammatory stimuli. Blood 1997;90:148-155
Web of Science | Medline2
Demeule M ,Labelle M ,Regina A ,Berthelet F ,Beliveau R . Isolation of endothelial cells from brain, lung, and kidney: expression of the multidrug resistance P-glycoprotein isoforms. Biochem Biophys Res Commun 2001;281:827-834
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van de Rijn M ,Heimfeld S ,Spangrude GJ ,Weissman IL . Mouse hematopoietic stem-cell antigen Sca-1 is a member of the Ly-6 antigen family. Proc Natl Acad Sci U S A 1989;86:4634-4638
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Gao Z ,McAlister VC ,Williams GM . Repopulation of liver endothelium by bone-marrow-derived cells. Lancet 2001;357:932-933
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Author/Editor Response
The authors reply:
To the Editor: The three letters raise questions about the chimerism of transplanted hearts based mainly on the fact that, so far, there are no published reports of the identification of human Sca-1–positive cells with the use of antibodies against the murine protein. Although we will deal with this concern below, the unambiguous fact is that documentation of myocyte, smooth-muscle, and endothelial chimerism is in no way dependent on the identification of Sca-1–positive cells. The isolation of Y-chromosome–positive cells and amplification of their DNA, which Bianchi et al. request, were not used in their work, might not be doable with fixed tissue, and are beyond the standard of this field.
The question of the identity of the “primitive cells” is raised in the three letters. We did not state that they were the stem cells responsible for the chimerism; we stated that they had characteristics that made them likely candidates. The presence of an epitope that specifically reacts with the Cedarlane anti–Sca-1 reagent in normal and abnormal human bone marrow has been confirmed in our laboratory. Similar small Sca-1–positive cells have been detected in hearts from mice, rats,1 and dogs. In addition, Western blots of human heart cells and umbilical-vein endothelial cells and murine bone marrow, thymus, spleen, kidney, heart, and small undifferentiated cells all show a 12-kD band, as would be expected with Sca-1 and other members of the Ly-6 family. Thus, it is unlikely that we “provided an example of rather high background levels,” as Spangrude et al. state. Instead, their negative results demonstrate that fluorescence-activated cell-sorter analyses are limited in their ability to identify antibody–epitope interactions that are not high affinity.
The possible inclusion of endothelial cells in the Sca-1 pool was avoided by excluding CD31, factor VIII, and vimentin. We have reported on studies of cardiac mast cells, and it is easy to recognize them.2 We examined hearts from four female controls, in which the Y chromosome was not detected. It is unlikely that these controls had clinical histories that differed from those of the eight patients with Y-chromosome–positive hearts. It would be unusual for male offspring, complications of pregnancy, blood transfusions from male donors, or a combination of these factors to account for the difference between control hearts and transplants. Bianchi et al. have found male fetal cells in women with damaged tissues or autoimmune diseases.3,4 Such conditions preclude transplantation. An important point is that the fraction of primitive cells expressing c-kit, MDR1, and Sca-1 that were negative for the Y chromosome was much larger than the fraction bearing the Y chromosome. Thus, undifferentiated and putative progenitor cells have been identified in human hearts, and chimerism has enhanced their number, leaving intact the notion that myocardial regeneration occurs in the transplanted heart.
4 ReferencesPiero Anversa, M.D.
Bernardo Nadal-Ginard, M.D., Ph.D.
New York Medical College, Valhalla, NY 10595
piero_anversa@nymc.edu 1
Anversa P ,Nadal-Ginard B . Myocyte renewal and ventricular remodelling. Nature 2002;415:240-243
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Olivetti G ,Lagrasta C ,Ricci R ,Sonnenblick EH ,Capasso JM ,Anversa P . Long-term pressure-induced cardiac hypertrophy: capillary and mast cell proliferation. Am J Physiol 1989;257:H1766-H1772
Web of Science | Medline3
Srivatsa B ,Srivatsa S ,Johnson KL ,Samura O ,Lee SL ,Bianchi DW . Microchimerism of presumed fetal origin in thyroid specimens from women: a case-control study. Lancet 2001;358:2034-2038
CrossRef | Web of Science | Medline4
Johnson KL ,Nelson JL ,Furst DE , et al. Fetal cell microchimerism in tissue from multiple sites in women with systemic sclerosis. Arthritis Rheum 2001;44:1848-1854
CrossRef | Web of Science | Medline
- Citing Articles (8)
Citing Articles
1
G. Földes, S.E. Harding. 2011. Stem Cell Therapy to Treat Heart Failure. , 407-423.
CrossRef2
Roberta Tasso, Andrea Augello, Simona Boccardo, Sandra Salvi, Michela Caridà, Fabio Postiglione, Franco Fais, Mauro Truini, Ranieri Cancedda, Giuseppina Pennesi. (2009) Recruitment of a Host's Osteoprogenitor Cells Using Exogenous Mesenchymal Stem Cells Seeded on Porous Ceramic. Tissue Engineering Part A 15:8, 2203-2212
CrossRef3
Christopher G.B. Turner, Dario O. Fauza. (2009) Fetal Tissue Engineering. Clinics in Perinatology 36:2, 473-488
CrossRef4
Dawn H. Siegel. (2008) Cutaneous Mosaicism: a Molecular and Clinical Review. Advances in Dermatology 24, 223-244
CrossRef5
Antoni Bayes-Genis, Beatriz Bellosillo, Oscar de La Calle, Marta Salido, Santiago Roura, Francesc Solé Ristol, Carolina Soler, Monica Martinez, Blanca Espinet, Sergi Serrano, Antoni Bayes de Luna, Juan Cinca. (2005) Identification of Male Cardiomyocytes of Extracardiac Origin in the Hearts of Women with Male Progeny: Male Fetal Cell Microchimerism of the Heart. The Journal of Heart and Lung Transplantation 24:12, 2179-2183
CrossRef6
Marije Koopmans, Idske C. L. Kremer Hovinga, Hans J. Baelde, Rosette J. Fernandes, Emile de Heer, Jan A. Bruijn, Ingeborg M. Bajema. (2005) Chimerism in Kidneys, Livers and Hearts of Normal Women: Implications for Transplantation Studies. American Journal of Transplantation 5:6, 1495-1502
CrossRef7
Nathalie C. Lambert, Timothy D. Erickson, Zhen Yan, Jennifer M. Pang, Katherine A. Guthrie, Daniel E. Furst, J. Lee Nelson. (2004) Quantification of maternal microchimerism by HLA-specific real-time polymerase chain reaction: Studies of healthy women and women with scleroderma. Arthritis & Rheumatism 50:3, 906-914
CrossRef8
Hagop Youssoufian, Reed E. Pyeritz. (2002) Mechanisms and consequences of somatic mosaicism in humans. Nature Reviews Genetics 3:10, 748-758
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