Figure 1.

Delivery of bone marrow mesenchymal stromal cells (BMSC) significantly extended the disease course and lifespan and supported MN survival when compared with vehicle-injected animals. Grafted MSCs significantly slowed the decline in limb grip strength (A) and motor performance of SOD1 rats (B), but did not affect the body weight loss (C). The Kaplan-Meier method shows significantly better survival of MSC-grafted SOD1 rats (D, F). The beginning of the disease did not differ between the two groups of SOD1 rats (E). MUNE in the medial gastrocnemius muscle showed no difference in motor unit numbers between MSC-treated and vehicle-injected SOD rats (G). The combination of IHC staining with an unbiased stereological method on serial sections of the spinal cord showed a significantly higher number of MN in MSC-treated animals at the cervical (H) and lumbar (I) levels. Arrows indicate the time of transplantation. Error bars indicate SEM. Significance at: *, p ≤ .05; **, p ≤ .01; ***, p ≤ .001. Abbreviations: BBB, Basso-Beattie-Bresnahan test; DMEM, Dulbecco's modified Eagle's medium; MN, motoneurons; MUNE, motor unit number estimation; SOD1, superoxide dismutase 1; WT, wild type.