Figure 1.

Class III semaphorins exert regulatory functions in multiple processes after CNS trauma by modulating various neuronal and non-neuronal cell types. Deposition of SEMA3s (black arrows) by invading fibroblasts from the ruptured meningeal layer and axotomized neurons has a large consequence for cellular remodeling and wound healing. The secreted SEMA3s have a wide range of biological effects on the resident glial cells and neurons, and additionally affect the blood derived cells that infiltrate the lesion core as a result of blood vessel rupture. As discussed in this review, the role of SEMA3s goes beyond inhibiting axonal regeneration and could be a significant target for future studies to stimulate repair following CNS trauma. Abbreviations: B-cell, B-lymphocyte; EC, endothelial cell; EGF, epidermal growth factor; OL, Oligodendrocytes; OPC, oligodendrocyte precursor cells; PDGF, platelet-derived growth factor; SC, Schwann cells; T-cell, T-lymphocyte; TGF-β, transforming growth factor—beta.