Fig. 1
Co-transplantation of sTreg cells and Lin− BMCs facilitates therapeutic correction in HA mice. a Scheme of the experiment. Lin− BMCs (0.25 × 106 cells) from female FVB-GFP mice (H2Kq) were transplanted into HA mice (H2Kb) through the tail vein within 30 h of acute liver injury, and the recipient mice were grouped as HAT-A. The Treg cells from HA mice were primed against donor MHC antigens by co-culturing with splenic DCs of FVB mice for 48 h to generate allo-antigen sensitized Treg cells (sTreg cells). To establish transplant tolerance, allogeneic Lin− BMCs and sTreg cells were co-transplanted into HA mice, and the recipient mice were grouped as HAT-AT. b Plasma FVIII activity was measured by in vitro coagulation assay performed by using a Coatest assay kit. FVIII activity as percentage of normal plasma in wild-type mice is shown. There was no significant increase in FVIII activity in HAT-A mice but the activity was much higher in HAT-AT mice (P < 0.0001, HAT-A versus HAT-AT mice) after 3 and 6 months of transplantation. c Capillary blood clotting time. WT, HA, HAT-A, and HAT-AT mice were subjected to the assay after 3 months of transplantation. d Tail-clip challenge test. Survival of mice after 24 h of tail clip was determined, and HAT-AT group showed no mortality. BM bone marrow, BMC bone marrow cell, DC dendritic cell, FVIII K/O factor VIII knockout, HA hemophilia A, HAT-A hemophilia A mice transplanted with allogeneic cells, HAT-AT hemophilia A mice transplanted with allogeneic and regulatory T cells, n number of mice in each experiment, sT reg sensitized regulatory T, WT wild-type