title: Olfactory ensheathing cells express smooth muscle alpha-actin in vitro and in vivo.
abstract: One strategy for spinal cord repair after injury that has moved quickly from the research laboratory to the clinic is the implantation of olfactory ensheathing cells (OECs). These unique glial cells of the olfactory system have been associated with axonal remyelination and regeneration after grafting into spinalized animals. Despite these promising observations, there remains a lack of direct empirical evidence of the exact fate of OECs after intraspinal implantation, in large part because of a surprising paucity of defined biomarkers that unequivocally distinguish these cells from phenotypically similar Schwann cells. Here we provide direct neurochemical proof that OECs, both in vitro and in vivo, express smooth muscle alpha-actin. That OECs synthesize this contractile protein (and a variety of actin-binding proteins including caldesmon) provides compelling evidence that these cells are, in fact, quite different from Schwann cells. The identification of several smooth muscle-related proteins in OECs points to a new appreciation of the structural and functional features of this population of olfactory glia. These biomarkers can now be used to elucidate the fate of OECs after intraspinal implantation, in particular assessing whether smooth muscle alpha-actin-expressing OECs are capable of facilitating axon remyelination and regeneration.
authors.affiliation: Department of Anatomy and Cell Biology, Queen's University, Kingston, Ontario, Canada.
authors.forename: Ali
authors.initials: A
authors.lastname: Jahed
authors.forename: James W
authors.initials: JW
authors.lastname: Rowland
authors.forename: Todd
authors.initials: T
authors.lastname: McDonald
authors.forename: J Gordon
authors.initials: JG
authors.lastname: Boyd
authors.forename: Ronald
authors.initials: R
authors.lastname: Doucette
authors.forename: Michael D
authors.initials: MD
authors.lastname: Kawaja
mesh_terms: D000199:Actins / Q000378:metabolism*; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002478:Cells, Cultured; D005260:Female; D008840:Microfilament Proteins / Q000378:metabolism*; D009186:Myelin Sheath / Q000378:metabolism*; D009416:Nerve Regeneration / Q000502:physiology; D009457:Neuroglia / Q000145:classification / Q000166:cytology / Q000378:metabolism*; D009831:Olfactory Mucosa / Q000166:cytology / Q000378:metabolism; D009832:Olfactory Nerve / Q000166:cytology / Q000378:metabolism; D009833:Olfactory Pathways / Q000166:cytology* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012583:Schwann Cells / Q000166:cytology / Q000378:metabolism; D012584:Sciatic Nerve / Q000166:cytology / Q000378:metabolism
chemical_list: D000199:Actins; D015415:Biomarkers; D008840:Microfilament Proteins