Abstract
As the primary mediator of immune response, the resident microglia is extremely sensitive to the damage in central nerve system (CNS). However the direct evidence to show its effect on injury repair is absent on account of the lack of appropriate approach to manipulate microglia. By using the CX3CR1^CreER/+: R26^iDTR/+ mice, in the present study we exclusively eliminate microglia right before the injury and maintain lower microglial population within two weeks. The short-term depletion of microglia results in the enlargement of lesion volume as well as the attenuation of sensory axon regeneration after spinal cord injury (SCI). Our results suggest that microglia play the protective roles at the early stage of SCI injury.