**4.2 Olfactory ensheathing glia cells**

Olfactory ensheathing glia cells (OEG) are a type of glial cells that are present in the olfactory system of adult mammals. In both acute and chronic injuries, OEGs have been shown to have the ability to promote axonal regeneration and help restore axonal conduction after TSCI [36].

Ramón-Cueto et al. demonstrated that OEG aided in the regrowth of sensory axons after spinal injury [37]. Doucette et al. described the survival of the OEG after having transplanted them in brain [38]. In contusion and transection models, the ability of OEGs to help protect the tissue after transplantation has been demonstrated, since they promote axonal growth and favor the improvement of locomotor function [39, 40]. OEGs have been said to have similar properties to Schwann cells and astrocytes, which make them unique. This cell type has two important benefits: they can exist both inside and outside the central nervous system, and they can be in constant neurogenesis, producing sensitive neurons in both embryonic and adult stages in mammals [41].
