Selective engraftment of bone marrow stromal cells in lumbar dorsal root ganglia and spinal cord from rats subjected to sciatic nerve lesion

M.F. CORONEL; P.L. MUSOLINO; M.J. VILLAR

Pisa, Italia

Congreso; Peripheral Nerve Society; 2005

Peripheral Nerve Society

Bone marrow stromal cells (MSCs) have been demonstrated to preferentially migrate into the injured hemisphere of rats subjected to a traumatic brain injury and improve the functional outcome of these animals. We now demonstrate that the intravenous administration of MSCs in rats subjected to a sciatic nerve lesion results in selective engraftment of the cells, not only in the lesioned nerve, but also in the ipsilateral lumbar dorsal root ganglia (DRG) and spinal cord (SC). Whole marrow was aspirated from the tibias and femurs of Sprague-Dawley rats, the mononuclear cells were isolated using a density gradient and plated at a concentration of 2-3 x 106 cells/ml in DMEM, 10% FBS in 25 cm2 cell culture flasks. MSCs were isolated by their adherence to plastic, cultured until they reached confluence, labeled with Hoechst 33258 and harvested using trypsin- EDTA. 1-2 x 106 cells were injected in the tail vein of adult Sprague-Dawley rats that had been subjected to a sciatic nerve lesion (crush or axotomy) two days before. The animals were perfused through the heart after 2, 7 and 10 days and the ipsi and contralateral sciatic nerves, lumbar DRGs and SC were dissected out. The tissues were processed for standard immunofluorescence, using multiple markers to determine the cellular phenotype of Hoechst-positive cells: STRO-1, GFAP, NeuN, b-III-tubulin. MSCs were selectively detected in the site of the injury in the lesioned nerve, as well as in the ipsilateral lumbar DRGs and SC. Differentiation into neural lineages could not be demonstrated. For this purpose, longer survival times are being studied, as well as the functional recovery of the animals, in order to evaluate a possible contribution of MSCs to nerve regeneration.