Comparative gene expression profiling of olfactory ensheathing glia and Schwann cells indicates distinct tissue repair characteristics of olfactory ensheathing glia

Abstract

Olfactory ensheathing glia (OEG) are a specialized type of glia that support the growth of primary olfactory axons from the neuroepithelium in the nasal cavity to the brain. Transplantation of OEG in the injured spinal cord promotes sprouting of injured axons and results in reduced cavity formation, enhanced axonal and tissue sparing, remyelination, and angiogenesis. Gene expression analysis may help to identify the molecular mechanisms underlying the ability of OEG to recreate an environment that supports regeneration in the central nervous system. Here, we compared the transcriptome of cultured OEG (cOEG) with the transcriptomes of cultured Schwann cells (cSCs) and of OEG directly obtained from their natural environment (nOEG), the olfactory nerve layer of adult rats. Functional data mining by Gene Ontology (GO)-analysis revealed a number of overrepresented GO-classes associated with tissue repair. These classes include "response to wounding," "blood vessel development," "cell adhesion," and GO-classes related to the extracellular matrix and were overrepresented in the set of differentially expressed genes between both comparisons. The current screening approach combined with GO-analysis has identified distinct molecular properties of OEG that may underlie their efficacy and interaction with host tissue after implantation in the injured spinal cord. These observations can form the basis for studies on the function of novel target molecules for therapeutic intervention after neurotrauma.

The glycoprotein fibulin‐3 regulates morphology and motility of olfactory ensheathing cells in vitro

“…Surprisingly little is known about basic OEC biology and the molecular repertoire that gives these cells their unique properties. To obtain more insight into the defining nature of OECs, several studies have now reported the use of proteomics and gene expression profiling in an attempt to identify novel target molecules that could contribute to the growth-promoting potential of these cells (Boyd et al, 2006;Franssen et al, 2008;Jahed et al, 2007;Ruitenberg et al, 2006;Vincent et al, 2005). The present study reports that the glycoprotein fibulin-3, also known as EFEMP-1, S1-5, or T16, is differentially expressed between Schwann cells and OECs.…”

Olfactory mucosa for transplant‐mediated repair: A complex tissue for a complex injury?

“…There have been many reviews written about the unique properties of OECs and their role in CNS repair (e.g. Franklin and Barnett, 2000;Barnett and Riddell, 2007;Franssen et al, 2008;Richter and Roskams, 2008;Wewetzer et al, 2002), and so they will only be briefly mentioned here. It is well documented that autologous rat OECs transplanted into rodent models of spinal cord injury prevent or reduce the development of lesion cavities and can remyelinate demyelinated axons (Boyd et al, 2003;Franklin and Barnett, 2000;Plant et al, 2003;Raisman, 2001;Ramon-Cueto and Valverde, 1995;Richter et al, 2008).…”

“…The main focus of attention in this tissue has been a unique class of glial cell, known as the olfactory ensheathing cell (OEC) that resides throughout the olfactory system (Barnett et al, 1993Doucette, 1990). There have been numerous studies of these cells, mainly in models of spinal cord injury and although some have reported improved functional out-come following OEC transplantation, a consensus on the full extent of their efficacy and mode of action has yet to be reached Franssen et al, 2008;Raisman and Li, 2007;Wewetzer et al, 2002). Despite this, several clinical trials or treatment programs using olfactory cells or tissues are now in progress (Feron et al, 2005;Guest et al, 2006;Huang et al, 2006;Lima et al, 2006;Mackay-Sim et al, 2008).…”

Comparison of bulbar and mucosal olfactory ensheathing cells using FACS and simultaneous antigenic bivariate cell cycle analysis

“…For clinical purposes, however, obtaining adult OECs for autografting by an intranasal approach to the olfactory mucosa would be preferable to the more invasive procedure of obtaining bulbar OECs by craniotomy. At the genomic level, the transcriptome profiles of purified OEC from OB and the mucosal LP revealed a pattern of differentially expressed genes, with the suggestion that bulbar OECs generally express genes associated with nervous system development, while mucosal OECs express genes associated with wound healing and extracellular matrix regulation (Franssen et al, 2008;Guerout et al, 2010).…”