The use of mesenchymal stromal cell (MSC) transplantation to repair the injured spinal cord has shown consistent benefits in
preclinical models. However, the low survival rate of grafted MSC is one of the most important problems. In the injured spinal
cord, transplanted cells are exposed to hypoxic conditions and exposed to nutritional deficiency caused by poor vascular
supply. Also, the transplanted MSCs face cytotoxic stressors that cause cell death. The aim of this study was to compare
adipose-derived MSCs (AD-MSCs) and bone marrow-derived MSCs (BM-MSCs) isolated from individual C57BL6/J mice in
relation to: (i) cellular characteristics, (ii) tolerance to hypoxia, oxidative stress and serum-free conditions, and (iii) cellular
survival rates after transplantation. AD-MSCs and BM-MSCs exhibited a similar cell surface marker profile, but expressed
different levels of growth factors and cytokines. To research their relative stress tolerance, both types of stromal cells were
incubated at 20.5% O2 or 1.0% O2 for 7 days. Results showed that AD-MSCs were more proliferative with greater culture
viability under these hypoxic conditions than BM-MSCs. The MSCs were also incubated under H2O2-induced oxidative stress
and in serum-free culture medium to induce stress. AD-MSCs were better able to tolerate these stress conditions than BMMSCs; similarly when transplanted into the spinal cord injury region in vivo, AD-MSCs demonstrated a higher survival rate
post transplantation Furthermore, this increased AD-MSC survival post transplantation was associated with preservation of
axons and enhanced vascularization, as delineated by increases in anti-gamma isotype of protein kinase C and CD31 immunoreactivity, compared with the BM-MSC transplanted group. Hence, our results indicate that AD-MSCs are an attractive
alternative to BM-MSCs for the treatment of severe spinal cord injury. However, it should be noted that the motor function
was equally improved following moderate spinal cord injury in both groups, but with no significant improvement seen
unfortunately following severe spinal cord injury in either grou