Feasibility of treating irradiated bone with intramedullary delivered autologous mesenchymal stem cells

We aimed to explore (i) the short-term retention of intramedullary implanted mesenchymal stem cells BMSCs and (ii) their impact on the bone blood flow and metabolism in a rat model of hindlimb irradiation.

Three months after 30 Gy irradiation, fourteen animals were referred into 2 groups: a sham-operated group (n = 6) and a treated group (n = 8) in which ¹¹¹In-labelled BMSCs (2 × 10⁶ cells) were injected in irradiated tibias. Bone blood flow and metabolism were assessed by serial (99m)Tc-HDP scintigraphy and 1-wk cell retention by recordings of (99m)Tc/¹¹¹In activities.

The amount of intramedullary implanted BMSCs was of 70% at 2 H, 40% at 48 H, and 38% at 168 H. Bone blood flow and bone metabolism were significantly increased during the first week after cell transplantation, but these effects were found to reduce at 2-mo followup. Conclusion. Short-term cell retention produced concomitant enhancement in irradiated bone blood flow and metabolism.