Bone Marrow Mesenchymal Stem Cells Increase Survival after Ionizing Irradiation Combined with Wound Trauma: Characterization and Therapy

The aim of this study was to investigate whether treatment with mesenchymal stem cells (MSCs) could improve survival after radiation combined injury. Bone marrow MSCs (BMSCs) were isolated from femurs of B6D2F1/J female mice and were expanded and cultivated in hypoxic conditions (5% O2, 10% CO2, 85% N2) over 30 days. BMSCs were transfused to mice 24 hr after combined injury due to 60Co-γ-photon irradiation (9.25 and 9.75 Gy, 0.4 Gy/min, bilateral) followed by skin wounding (CI). Water consumption, body weight, wound healing, and survival tallies were monitored during observation period. Mice subjected to CI experienced a dramatic moribundity over a 30-day observation period. Thus, CI (9.25 Gy)-animal group was characterized by 40% mortality rate while CI (9.75 Gy)-animal group had 100% mortality rate. CI-induced sickness was accompanied by body weight loss, increased water intake, and delayed wound healing. At the 30th day post-injury, bone marrow cell depletion still remained in surviving CI mice. Treatment of CI (9.25 Gy)-animal group with BMSCs led to an increase in 30-day survival rate by 30%, attenuated body weight loss, accelerated wound healing rate, and ameliorated bone-marrow cell depletion. Our novel results are the first to suggest that BMSC therapy is efficacious to sustain animal survival after CI.