Ependymocytes
Ependymocytes are one of the three types of ependymal cells, which in turn are one of the four principles types of glial cells, and are found lining the ventricular system of the brain and the central canal of the spinal cord .
They do not form a water-tight barrier between the cerebrospinal fluid (CSF) and extracellular fluid of the brain parenchyma, rather allowing flow between the two compartments .
Histology
Ependymocytes have a variable number of cilia and microvilli on their luminal surface .
Interestingly the ependymal lining of the ventricles regionally deficient, particularly at the frontal horns (see ependymitis granularis), and becomes progressively less complete with age .
Immunohistochemistry
- glial fibrillary acid protein (GFAP): positive (see below)
- epithelial membrane antigen (EMA): positive
There is debate about the relationship of normal and neoplastic ependymocytes and staining for GFAP. Both neoplastic, and to a lesser degree normal ependymocytes to demonstrate a positive reaction for GFAP . This may, however, represent a positive reaction to intermediate filaments that are similar, rather than to GFAP itself which is absent in normal adult ependymocytes .
See also
