Olfactory Ensheathing Cells is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
| Olfactory Ensheathing Cells (OECs) | |
|---|---|
| Cell Type | Glial-like progenitor |
| Lineage | Neural crest > Olfactory ensheathing glia |
| Marker Genes | S100β, GFAP, p75^NTR, NGFR, Sox10, OMP |
| Brain Regions | Olfactory epithelium, olfactory bulb, rostral migratory stream |
| Allen Atlas ID | Not applicable (not in rodent cell type atlas) |
Olfactory Ensheathing Cells (OECs) are a unique population of glial-like cells that ensheath olfactory nerve axons throughout the olfactory system. They share properties with both astrocytes and Schwann cells, making them uniquely positioned to support olfactory neuron regeneration throughout life. OECs are among the few neural cell types that retain robust regenerative capacity in adulthood, providing a model for understanding neural repair mechanisms with potential therapeutic applications in neurodegeneration.
OECs exhibit distinctive morphological characteristics that distinguish them from other glial cell types:
| Marker | Expression | Function |
|---|---|---|
| S100β | High | Calcium-binding protein, proliferation regulation |
| GFAP | Variable | Intermediate filament, reactive gliosis |
| p75^NTR | High | Nerve growth factor receptor, apoptosis regulation |
| NGFR | High | Neurotrophin receptor |
| Sox10 | Moderate | Transcription factor, glial lineage |
| OMP | Low | Olfactory marker protein, maturation marker |
| Nestin | High | Intermediate filament, progenitor marker |
The olfactory system maintains continuous neurogenesis throughout adulthood, requiring OEC support:
OECs provide critical support for olfactory circuit function:
OECs retain exceptional regenerative capacity:
Olfactory impairment is among the earliest and most common features of several neurodegenerative diseases:
| Disease | Olfactory Involvement | OEC Relevance |
|---|---|---|
| FTLD | Variable olfactory deficits | TDP-43 pathology in OECs |
| ALS | Olfactory dysfunction in some patients | Limited OEC studies |
| Huntington's Disease | Early olfactory deficits | OEC role unclear |
| MS | Olfactory dysfunction common | OEC transplantation studies |
OECs have attracted significant interest for cell therapy:
While OECs are not extensively characterized in the Allen Brain Atlas, single-cell studies reveal distinct populations:
| Gene | Expression | Relevance |
|---|---|---|
| S100b | High | Calcium signaling |
| Gfap | Variable | Glial identity |
| Ngfr | High | Neurotrophin response |
| Plp1 | Moderate | Myelin structural protein |
| Dhh | Moderate | Hedgehog signaling |
| Sox10 | Moderate | Glial transcription factor |
| Cx43 | High | Gap junction communication |
| Kir4.1 | Moderate | Potassium buffering |
Barnett SC, Roskams AJ. Olfactory ensheathing cells: unique glial cell population. Prog Brain Res. 2002;137:321-332. DOI:10.1016/S0079-6123(0237024-4
Mackay-Sim A, St John JA. Olfactory ensheathing cells from the nose: clinical application in human spinal cord injuries. Exp Neurol. 2011;229(1):174-180. DOI:10.1016/j.expneurol.2010.08.025
Suarez-Rodriguez F, Belkind-Gerson J. Cultured olfactory ensheathing cells: neural progenitors for spinal cord repair. Transplant Proc. 2008;40(2):602-604. DOI:10.1016/j.transproceed.2008.01.045
Choi D, et al. Olfactory ensheathing cells: characteristics and potential for spinal cord injury repair. Neurosurgery. 2008;63(3):540-547. DOI:10.1227/01.NEU.0000324899.43611.C5
Ramon-Cueto A, et al. Functional recovery after transection of the rat spinal cord: transplantation of olfactory ensheathing glia. Restor Neurol Neurosci. 2001;19(1-2):135-139.
Zhang Y, et al. Olfactory dysfunction in neurodegenerative diseases. Curr Alzheimer Res. 2022;19(8):571-585. DOI:10.2174/1567205019666220926104703
Doty RL. Olfactory dysfunction in neurodegenerative diseases: is there a common pathological substrate? Lancet Neurol. 2017;16(6):478-488. DOI:10.1016/S1474-4422(1730144-1
Moberg PJ, et al. Olfactory dysfunction in schizophrenia and Parkinson's disease: implications for neurosurgery. Neurosurgery. 2022;90(3):487-501. DOI:10.1227/NEU.0000000000001834
The study of Olfactory Ensheathing Cells has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
[1] Graziadei PP, Graziadei GA. Neurogenesis and neuron regeneration in the olfactory system of mammals. I. Morphological aspects of differentiation and structural organization of the olfactory sensory neurons. J Neurocytol. 1979;8(1):1-18. PMID:42203.
[2] Doetsch F, Caille I, Lim DA, García-Verdugo JM, Alvarez-Buylla A. Subventricular zone astrocytes are neural stem cells in the adult mammalian brain. Cell. 1999;97(6):703-716. PMID:10380923.
[3] Mackay-Sim A, Chuah MI. Neurotrophic factors in the olfactory bulb. Int J Dev Neurosci. 2000;18(7):671-679. PMID:11051272.
[4] Raisman G. Specialized glial cells tunnel axons in the adult CNS: roles in myelination and mapping the chemical environment. Prog Brain Res. 2001;132:91-99. PMID:11545098.
[5] Iwatsuki K, Yoshikawa M, Nakamura T, et al. Olfactory ensheathing cell transplantation for spinal cord injury: A prospective non-randomized controlled trial. J Clin Neurosci. 2018;58:132-136. PMID:30337231.
[1] Barnett SC, Chang L. Olfactory ensheathing cells and CNS repair. Neuroscientist. 2004;10(2):93-97. DOI:10.1177/1073858403261222
[2] Raisman G. Olfactory ensheathing cells - unique glial cells. Brain Res Rev. 2007;55(1):186-191. DOI:10.1016/j.brainresrev.2007.02.010
[3] Moreno-Flores MT, Wandosell F. Olfactory ensheathing cell migration: mechanisms and roles in neural repair. Neuroscientist. 2008;14(5):460-475. DOI:10.1177/1073858408318508