Regenerative responses to stab wound injury. Lesions introduced by a syringe needle induce a proliferative response in the periventricular region of the stabbed hemisphere. Oligodendrocytes and microglial cells accumulate at the site of lesion. The glial marker GFAP and the proliferation marker PCNA are upregulated in the lesioned hemisphere. The number of T-box brain gene 2-positive (Tbr2+) cells is increased upon injury . The injury is totally healed after 30 days without traces of a glial scar. Schematic shows transverse section through the medial telencephalon.