Fig. 7

Transplantation of human Tregs together with iVECs into FTY720-treated animals promoted remyelination. A The timeline for the experimental procedure in this experiment is shown. Endothelin-1 was injected into the left IC to induce infarction on day 0. iVECs, Tregs isolated and expanded from human PBMCs, or bovine serum albumin (BSA) were injected into each animal on day 7. Some animals received intraperitoneal administration of FTY720 daily from day 7 to day 14. B A phase contrast image of cultured human Tregs on day 7. Scale bar: 200 µm. C FACS analysis for the marker expression of cultured human Tregs. (i) CD4⁺ T cells, (ii) CD25⁺Foxp3⁺ Tregs. D (i) Immunohistochemical images for STEM121 and Foxp3 in the iVEC- and Treg-transplanted brain section on day 14. (ii) Higher magnification image of the inset in (i). Nuclei were stained by Hoechst 33,342. Scale bars: 100 µm (i) and 50 µm (ii). E Immunohistochemical images for Olig2 and the quantification of Olig2⁺ cells in iVEC- and iVEC + Treg-transplanted animals treated with FTY720 on day 14. Nuclei were stained by Hoechst 33342. Scale bar: 50 µm. All data are expressed as mean ± SEM. n = 5 in each group. ns, no significant difference. F Representative LFB staining images of iVEC- and iVEC + Treg-transplanted brain sections and quantification of the damaged IC volume in each group on day 14. Scale bar: 500 µm. All data are expressed as mean ± SEM. n = 5 in each group. ^***p < 0.001. These experiments were repeated three times using human Tregs obtained from three different donors, and similar results were obtained each time. Typical experiments are shown here