AbstractOlfactory ensheathing cells (OEC) have the ability to promote regeneration in the nervous system. Hence, they hold promise for cell therapy. Most of the experimental studies have investigated the role of OECs taken from olfactory bulb (OB). However, for a clinical human application, olfactory mucosa (OM) seems to be the only acceptable source for OECs. Many studies have compared the distinct ability of OECs from OB and OM to improve functional nerve regeneration after lesion of the nervous system. Nevertheless, the two populations of OECs may differ in several points, which might affect all fate after transplantation in vivo. We report here the first study which compares gene expression profiling between these two populations of OECs. It appears that OB‐OECs and OM‐OECs display distinct gene expression pattern, which suggest that they may be implicated in different physiological processes. Notably, OM‐OECs overexpress genes characteristic of wound healing and regulation of extra cellular matrix. In contrast, OB‐OECs gene profile suggests a prominent role in nervous system development. Hence, OB‐OECs and OM‐OECs fundamentally differ in their gene expression pattern, which may represent a crucial point for future clinical application. © 2010 Wiley‐Liss, Inc.