Reelin expression and secretion by olfactory ensheathing cells

Olfactory ensheathing cells (OECs) contribute to axon guidance and fascicle organization during the cyclical degeneration and regeneration in the olfactory system throughout life. OECs also support neurite outgrowth in vitro and axon regeneration following spinal cord injury. Reelin, a large extracellular matrix protein, is responsible for proper neuronal positioning of migrating neurons in the neocortex and spinal cord of the developing nervous system. Because OECs share phenotypic characteristics with Schwann cells and the absence of Reelin may impair peripheral nerve regeneration (Lorenzetto et al., 2008; Vincent et al., 2005), we asked if OECs express Reelin to mediate neural repair after injury. Here we show that olfactory bulb OECs produce and secrete Reelin. We also determined that Reelin secretion is a potential mechanism by which OECs can mediate process outgrowth. OEC-secreted Reelin did not enhance neurite outgrowth of postnatal cerebral cortical neurons, but did mediate enhanced outgrowth of DRG axons