Exogenous BDNF enhances the integration of chronically injured axons that regenerate through a peripheral nerve grafted into a chondroitinase-treated spinal cord injury site

► ChABC promotes long injured axons to regenerate beyond a grafted injury site. ► Overexpression of BDNF in distal tissue did not enhance axonal regeneration. ► Regenerated axons formed synapses upon more neurons with BDNF treatment. ► BDNF is not sufficient to promote axonal regeneration but does promote integration.