Quick Facts
Glial cells are the cells of the supportive tissue of the central nervous system (neuroglia); these nonneural cells are of three kinds: astrocytes, oligodendrocytes (collectively termed macroglia), and microglia (Dorland, 2011).
Structure and/or Key Features
Olfactory glia originate in the olfactory system, arising originally from neural crest cells. They ensheath the axons of the olfactory sensory neurons in an unusual way that differs from the rest of the nervous system. They follow the olfactory sensory neurons through the lamina propria and the cribriform plate, to their synaptic terminals in the glomerular layer of the olfactory bulb. This enables them to guide the olfactory axons to the accurate location in the olfactory bulb. This unique configuration, unlike the rest of the nervous system, blurs the distinction between the territories of the central and peripheral nervous systems transition zones (Standring, 2016)
Although olfactory glia have similar morphological and antigenic characteristics with astrocytes and non-myelinating Schwann cells, they have clear-cut attributes that define them. However, just like Schwann cells, olfactory glia can myelinate axons (Standring, 2016).
The olfactory glia, along with astrocytes situated between the olfactory axons, contribute to the glia limitans at the pial aspect of the olfactory bulbs.
Anatomical Relations
The olfactory glia are situated in the lamina propria of the olfactory mucosa and the outer nerve layer of the olfactory bulb (Zigova, Sanberg and Sanchez-Ramos, 2002).
Function
Olfactory glia guide the olfactory axons to their accurate positions in the olfactory bulb. Because the olfactory system is unique as it is one of the only tissues in the central nervous system that supports neurogenesis throughout life, olfactory glia can be useful in transplant-mediated cell repair via stem cells (Standring, 2016).
Clinical Correlates
—Spinal cord injuries
References
Dorland, W. (2011) Dorland's Illustrated Medical Dictionary. 32nd edn. Philadelphia, USA: Elsevier Saunders.
Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edition: Elsevier Limited.
Zigova, T., Sanberg, P. R. and Sanchez-Ramos, J. R. (2002) Neural Stem Cells: Methods and Protocols. Methods in molecular biology: Humana Press.
