Caudal to the injury epicenter (P <0.05). No significant difference…

Caudal to the injury epicenter (P 0.05). This was clearly shown when the volume (mm3) of the white matter was compared in five different parts of the spinal cord (front, 7 to 10 mm cranial; middle front, 3 to 6 mm cranial; center, between 2 mm cranial and caudal to the injury epicenter; middle back, 3 to 6 mm caudal; back, 7 to 10 mm caudal) (Figure 3B). No statistically significant differences were found around the injury epicenter (P > 0.05). The sparing of the white matter was Staurosporine prominent throughout the spinal cord, apart from the injury epicenter and the transplanted area.In vivo cell survival and differentiationSPC-01 cells were tested in the lesioned rat spinal cord in terms of their survival and differentiation into neuronal and glial phenotypes. In total, 5 ?105 cells were implanted into the center of a spinal cord lesion. The engrafted cells were identified either by GFP positivity or by immunohistochemical staining for the human-Amemori et al. Stem Cell Research Therapy 2013, 4:68 http://stemcellres.com/content/4/3/Page 8 ofFigure 2 T2-weighted MR images of the injured spinal cord before and after SPC-01 cell transplantation. T2-weighted MR images of a spinal cord lesion 5 days after lesion induction, before transplantation (A), a spinal cord with a cell graft 8 weeks after cell transplantation (B), and a control spinal cord lesion 8 weeks after saline injection (C). Two serial sections were stained for MTC02 (D) and iron (E) and their overlay (F).specific markers HuNu or MTCO2. Because the majority of the grafted cells lost their GFP positivity 8 weeks after transplantation, we therefore had to rely on staining for human-specific markers (Figure 4A). The animals were killed 8 or 17 weeks after transplantation, and cell survival was evaluated by examining serial longitudinal sections of the lesioned spinal cord at both time points. The results showed that the cells robustly survived in the lesion: during the entire experiment, we found grafts in 19 of 20 animals. Grafted cells also did not form tumors during the entire period of observation, and 8 weeks after transplantation, the Ki67 index was 3.24 ?0.12 . The cells formed several "densely packed clouds" and filled the lesioned tissue over a few millimeters along the longitudinal axis of the spinalcord (Figure 4A), creating their own microenvironment with a few host cells. When the cells came into close contact with the uninjured spinal cord tissue, they grew into the host tissue: some cell bodies spread out of the cell mass into the host tissue and extended their processes (Figure 4A1). Quantitative analyses of the survival of SPC-01 cells were made from serial cross sections. The total volume of the cell mass remaining 8 weeks after transplantation was 0.29 mm3 ?0.06 mm3 on average, and the percentage of surviving SPC-01 cells was 17.4 ?2.7 . Eight weeks after transplantation, grafted cells expressed early neural markers such as NSE and nestin, the early oligodendroglial marker Olig2, and the astroglial marker GFAP (all data shown in Additional file 4: Figure S2).Figure 3 Morphometric evaluation of the spared white and gray matter. The white matter (WM) was significantly spared in the spinal cord of grafted animals compared with SCI-only animals (*P PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/7500280 (GM) (A). This was confirmed by measuring the volume (mm3) of the white matter in five di.