Persistence of allografts in the peritoneal cavity after prenatal transplantation in mice.
BACKGROUND
In utero transplantation (IUT) is usually performed by intraperitoneal injection, but there is little information regarding the fate of intraperitoneally transplanted cells in the first weeks after transplantation.


METHODS
Fetal transplantation was performed in a B6D2F(1) (C57BL/6 x DBA/2, H-2(b)/(d)) into C57BL/6 (H-2(b)) murine strain combination at the gestational age of 13 days by intraperitoneal injection of light-density marrow cells. Adult C57BL/6 mice were used as the postnatal transplantation group. Donor cell levels in the peritoneum, peripheral blood, and various hematopoietic tissues were examined by flow cytometry.


RESULTS
After fetal transplantation, peritoneal chimerism could be detected for 4 weeks, ranging from 0.02 to 23.2 percent with the highest median chimerism at 2 weeks after transplantation. Donor cells in the peripheral blood, spleen, marrow, liver, and thymus were usually low (<0.2%) with a tendency for higher donor cell levels at 2 weeks after transplantation. Engraftment in fetal peritoneum was primarily by myeloid and B cells with few T cells. In contrast, adult mice transplanted with haplogeneic marrow cleared nearly all donor cells from the peritoneum within a week of transplant. There was no evidence showing that donor cells had ever migrated to any hematopoietic tissues after adult transplantation.


CONCLUSIONS
Despite limited engraftment in hematopoietic tissues, donor cells persisted in the peritoneum for 2 weeks or longer after fetal transplantation. The fetal peritoneum may serve as a sanctuary for foreign cells in the fetus, which may aid the development of novel cellular therapies for birth defects.
Chen
Jeng-Chang
JC
Department of Surgery, University of California, San Francisco, California, USA.
Chang
Ming-Ling
ML
Muench
Marcus O
MO
D000818:Animals; D016026:Bone Marrow Transplantation / Q000379:methods; D005260:Female; D005333:Fetus / Q000601:surgery; D006085:Graft Survival / Q000502:physiology; D007274:Injections, Intraperitoneal; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008815:Mice, Inbred Strains; D010529:Peritoneal Cavity; D011247:Pregnancy; D018183:Transplantation Chimera / Q000196:embryology / Q000502:physiology*; D014184:Transplantation, Homologous / Q000502:physiology*