FUNCTIONAL RECOVERY INDUCED BY SECRETOME OF NEUROECTODERMAL STEM CELLS AFTER SPINAL CORD INJURY
Spinal cord injury results in irreversible tissue damage followed by limited recovery of function. We have earlier proved that grafted cells of the neuroectodermal stem cell line NE-GFP-4C induces significant functional recovery supported by neuroprotection and extensive axonal regeneration. The grafted cells produced GDNF, IL-6, IL-10 and MIP-1a. We hypothetise that intraspinal delivery of these factors into the injured spinal cord may be able to induce as good morphological and functional recovery as the grafted neuroectodermal stem cells. A contusion injury was performed at the level of Th11 vertebra. The delivery of secretome started 7 days after injury either via osmotic pumps or transfected fibroblast directly into the lesion cavity. Animals in the control groups received saline or fibroblast. In the positive controls NE-GFP-4C cells were grafted intraspinally. Locomotor analysis of the animals was performed through the use of the BBB-test and a detailed kinematic analysis system. The extent of supra- and propriospinal axonal sparing/regeneration was determined by retrograde tracing with Fast Blue. The factors adminestered through the use of osmotic pump or transfected fibroblast induced significantly improved functional recovery compared to controls. Larger number of retrogradely labelled neurons found in the treated animals suggested improved axonal connections. The extent of the contusion cavity and the amount of spared white and gray matter were significantly greater in the treated cords. These results suggest that the secretome-based treatment is a promising putative therapeutic approach to treat spinal cord injury.