Blood Chimerism in Dizygotic Monochorionic Twins During 5 Years Observation

• Published in: American journal of transplantation Vol. 17; no. 10; pp. 2728 - 2732
• Main Authors: Dziegiel, M. H., Hansen, M. H., Haedersdal, S., Barrett, A. N., Rieneck, K., Main, K. M., Hansen, A. T., Clausen, F. B.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Limited 01.10.2017
• Subjects: Autografts; basic (laboratory) research/science; Benign; Bone marrow; bone marrow/hematopoietic stem cell transplantation; Case reports; Chimerism; clinical research/practice; Erythrocytes; Flow Cytometry; Hematological diseases; Hematology; Humans; immunobiology; Immunological tolerance; immunosuppression/immune modulation; Polymerase chain reaction; Polymerase Chain Reaction - methods; reproductive biology; Sickle cell disease; Stem cell transplantation; Stem cells; Thalassemia; tolerance; tolerance: chimerism; Transplantation; Twins, Monozygotic; reproductive biology; stem cells; tolerance: chimerism; immunosuppression/immune modulation; clinical research/practice; bone marrow/hematopoietic stem cell transplantation; immunobiology; tolerance; basic (laboratory) research/science
• ISSN: 1600-6135; 1600-6143
• DOI: 10.1111/ajt.14318

Dizygotic monochorionic twin pregnancies can result in blood chimerism due to in utero twin‐to‐twin exchange of stem cells. In this case, we examined the proportion of allogeneic red blood cells by flow cytometry and the proportion of allogeneic nucleated cells by digital polymerase chain reaction at 7 months and again at 5 years. We found an increase in the proportion of allogeneic cells from 63% to 89% in one twin, and a similar increase in autologous cells in the other twin from 57% to 84%. A paradigm for stem cell therapy could be modeled on this case: induction of tolerance and chimerism by antenatal transfusion of donor stem cells. The procedure would hold the promise of transplantation and tolerance induction without myeloablative conditioning for inheritable benign hematological diseases such as sickle cell disease and thalassemia. A substantial chimerism present at delivery and spontaneously increasing indicates that antenatal transfusion of stem cells could be a treatment for inheritable benign hematological diseases.