Intrauterine stem cell therapy (IUSCT) refers to treatment of a variety of fetal genetic disorders thought transplantation of either allogenic or genetically modified autologous stem cells. Stem cells become incorporated into the recipient tissue to start proliferation and differentiation through their pluripotent or multipotent potential to compensate for the missing or defective protein. This could be useful in treating fetal genetic disorders which are considered to be perinatally lethal or associated with significant disability and morbidity if intervention is delayed to postnatal period (1).
Recent advances in prenatal diagnostic techniques have enabled early prenatal diagnosis of a wide variety of genetic disorders. IUSCT has the following advantages over postnatal therapy: the immune system of the fetus at early gestation is still immature; which is the basis for the unique immunologic tolerance phenomenon described many years ago (2). Such tolerance allows incorporation of the donor stem cells (engraftment) without need for myeloablation or use of immunosuppressors. Also, the sterile environment inside the uterus facilitates remodeling of the fetal immune system (3). Another major advantage of IUSCT is small size of the fetus at early gestation compared to postnatal size allowing transfusion of higher concentrations of stem cells (4). These factors contribute to the promising potential of IUSCT in managing wide variety of genetic disorders.
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