BoneKEy Reports | BoneKEy Watch

Umbilical cord blood stem cells replenish mesenchymal cell lineages



DOI:10.1038/bonekey.2012.213

It is already known that umbilical cord blood had the ability to replenish hematopoietic stem cells in irradiated animals, but the full extent of the bone marrow engraftment was unclear. In this study, Uchida et al. investigated whether a cord blood transplant in mice resulted in reconstruction of the mesenchymal cell lineages involved in bone fracture repair.

Mice that had been irradiated to deplete their bone marrow were injected intravenously with mesenchymal cells obtained from the umbilical cord blood of GFP-positive transgenic mice. This allowed engraftment to be monitored, as transplanted cells emitted a strong and easily detectable fluorescent signal. Three months after transplantation an experimental fracture was induced and both the rate of healing and the cells involved in the fracture repair were assessed in the transplanted mice.

By day 14, the fracture site had started to heal and the intramedullary callus and newly formed woven bone contained fluorescent cells, confirming that engrafted cells from the transplant had resulted in replenishment of mesenchymal cells capable of osteoblastic activity.

Editor's comment: This study demonstrates that, in mice at least, GFP-tracked umbilical cord blood-derived cells replenish the hematopoietic and mesenchymal lineages that migrate to a fracture site to stimulate fracture repair and healing.


Creative Commons License This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.