Moustafa ME, Srivastava AS, Nedelcu E, Donahue J, Gueorguieva I, Shenouda SS, Minev B, Carrier E. Transplantation. 2004 Nov 15;78(9):1274-82.
Background: Clinical application of in utero transplantation (IUT) in human fetuses with intact immune systems resulted in a very low level of donor chimerism. In this study, we examined whether the fetal immune system early in the second trimester of pregnancy (13.5 dpc) can initiate immune tolerance for major histocompatibility complex (MHC)-mismatched embryonic stem (ES) cells. We also examined whether immune tolerance mechanisms respond differently to ontogenetically different stem cells.
Methods: MHC-mismatched ES, fetal liver (FL), and bone-marrow (BM) cells (H-2kd) at 1 x 10(9) cells/kg fetal body weight were injected intraperitoneally into 13.5 dpc BALB/c fetuses (H-2Kd). Peripheral chimerism was determined in blood by flow cytometry (sensitivity< or =0.1%) at monthly intervals.