Effects of implantation site of dead stem cells in rats with stroke damage

Searching for valid control grafts, we assessed the performance of rats subjected to middle cerebral artery occlusion (MCAO) and grafted with freeze-thawed dead stem cells into sites previously used for active grafts (ipsilateral and contralateral striatum and ventricle) on bilateral asymmetry and water maze tests. We expected to find that sham grafted groups had impairments equivalent to those of MCAO-only controls, relative to intact controls. This proved to be the case for contralateral and intraventricular grafts, and for asymmetry in rats with ipsilateral grafts. However, spatial learning was substantially impaired and lesion volume was increased by 55% with ipsilateral dead cell grafts. Exacerbation of stroke effects indicates potential hazards in the use of dead cells for sham grafts.