title: Gender-dependent survival of allogeneic trophoblast stem cells in liver.
abstract: In view of the well-known phenomenon of trophoblast immune privilege, trophoblast stem cells (TSCs) might be expected to be immune privileged, which could be of interest for cell or gene therapies. Yet in the ectopic sites tested so far, TSC transplants fail to show noticeable immune privilege and seem to lack physiological support. However, we show here that after portal venous injection, green fluorescent protein (GFP)-labeled TSCs survive for several months in the livers of allogeneic female but not male mice. Gonadectomy experiments revealed that this survival does not require the presence of ovarian hormones but does require the absence of testicular factors. By contrast, GFP-labeled allogeneic embryonic stem cells (ESCs) are reliably rejected; however, these same ESCs survive when mixed with unlabeled TSCs. The protective effect does not require immunological compatibility between ESCs and TSCs. Tumors were not observed in animals with either successfully engrafted TSCs or coinjected ESCs. We conclude that in a suitable hormonal context and location, ectopic TSCs can exhibit and confer immune privilege. These findings suggest applications in cell and gene therapy as well as a new model for studying trophoblast immunology and physiology.
authors.affiliation: Department of Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Epple-Farmer
authors.forename: Bisrat G
authors.initials: BG
authors.lastname: Debeb
authors.forename: Oliver
authors.initials: O
authors.lastname: Smithies
authors.forename: Bert
authors.initials: B
authors.lastname: Binas
mesh_terms: D000818:Animals; D002369:Castration; D002450:Cell Communication; D002460:Cell Line; D053595:Embryonic Stem Cells / Q000166:cytology / Q000502:physiology* / Q000637:transplantation*; D005260:Female; D012739:Gonadal Steroid Hormones / Q000378:metabolism; D049452:Green Fluorescent Proteins; D006648:Histocompatibility; D007275:Injections, Intravenous; D008099:Liver / Q000166:cytology* / Q000502:physiology*; D008297:Male; D051379:Mice; D011169:Portal Vein; D012737:Sex Factors; D023001:Transplantation Tolerance; D014184:Transplantation, Homologous; D014327:Trophoblasts / Q000166:cytology / Q000502:physiology* / Q000637:transplantation*
chemical_list: D012739:Gonadal Steroid Hormones; D049452:Green Fluorescent Proteins