Endogenous Proliferation after Spinal Cord Injury in Animal Models
Figure 1
Qualitative summary of the features of the three types of animal models of SCI. Diagrams were created based on the references listed in Table 1. (a) Examples of transection injuries include dorsal hemisections (left), lateral hemisections (right), and complete transection (bottom). Proliferation peaks at 3 dpi and tapers off by 9 dpi. The mitotic response to injury is localized to the epicenter. Transection injuries are characterized by daughter cells acquiring astrocyte and macrophage/microglia fates. These cell types migrate to the region of injury. Depicted in the two right-most diagrams is proliferation and cell fate preferences in a dorsal hemisection injury. (b) A contusion injury typically results in a rim of spared white tissue. In response to injury, proliferation peaks at 3 dpi and is elevated for 14 days. Contusion injuries are characterized by a proliferative response that spans the rostrocaudal extent of the spinal cord. Cell fate of mitotic cells trends towards the oligodendrocyte lineage, but astrocytes and microglia also represent a portion of dividing cells. (c) Compression injuries closely resemble contusion injuries both in the extent of the spinal cord affected and cell types generated.
