, 2006 and Martin et al., 1996). Lu et al., 2001 and Lu
et al., 2002 showed a great improvement in hindlimb motor function, spinal reflex and enhanced regeneration of raphespinal fibers with OLP transplantation immediately or 4 weeks after spinal cord INCB018424 nmr transection. On the other hand, Steward et al. (2006) failed to find evidence of functional recovery and showed only limited regeneration of raphespinal axons after spinal cord transection and 4-week delayed OLP transplantation. In our study, functional recovery, tissue sparing and axon sprouting/regeneration outcomes were comparable between animals with OLP or RLP grafts, uninfluenced by the different transplantation times (acute, 2 weeks or 4 weeks post-injury). Raphespinal axons rarely extended beyond the lesion border, but CGRP fibers were evident in the center of the lesion after both types of transplants. Thus, the optimal time-window for cellular ABT-263 supplier or tissue transplantation continues to be ill-defined, but this parameter does not seem to limit the effects obtained from the grafts. In addition, as CGRP axon regeneration may be related to nociception transmission, interventions that
favor axonal regeneration after SCI must be controlled to ensure that appropriate rather than inappropriate connections are restored (Richter et al., 2005). Despite current controversy in animal studies, clinical trials using cultured OECs from lamina propria or olfactory mucosa grafts have been made in chronically injured humans
(Chhabra et al., 2009, Féron et al., 2005, Lima et al., 2006, Lima et al., 2010 and Mackay-Sim et al., 2008). There is still divergence regarding the functional results and, moreover, the procedures used in some of these studies were not administered according to formal clinical trial protocols (Mackay-Sim and St John, 2011). Acute, 2-week or 4-week delayed OLP and RLP transplantation produced a discrete functional recovery over time and comparable CGRP fiber sprouting in the lesion site, but failed to produce regeneration of raphespinal descendent fibers. OECs Cepharanthine are only one cell type found in olfactory mucosa, which is a tissue of considerable cellular complexity. This is particularly relevant when clinical trials involving the transplantation of these tissue samples in a complex injury such as the damaged central nervous system are conducted (Lindsay et al., 2010). A better understanding of the effects of OLP and RLP transplantation in SCI animal models is necessary in order to strengthen the rationale for the application of this treatment in humans. Additionally, cells transplants combined with other therapies, such as the administration of MAG, OMP and NOGO-A inhibitors, growth-factors, and/or treadmill step training may increase the possible beneficial results after spinal cord injury. Experimental procedures were approved by the Research Ethics Committee of the Universidade Federal do Rio Grande do Sul (No. 2007892).