Epithelial reticular cells, or epithelioreticular cells (ERC), some called thymic epithelial cell (TEC), are a structure in both the
cortex
Cortex or cortical may refer to:
Biology
* Cortex (anatomy), the outermost layer of an organ
** Cerebral cortex, the outer layer of the vertebrate cerebrum, part of which is the ''forebrain''
*** Motor cortex, the regions of the cerebral cortex i ...
and
medulla
Medulla or Medullary may refer to:
Science
* Medulla oblongata, a part of the brain stem
* Renal medulla, a part of the kidney
* Adrenal medulla, a part of the adrenal gland
* Medulla of ovary, a stroma in the center of the ovary
* Medulla of ...
of the
thymus
The thymus is a specialized primary lymphoid organ of the immune system. Within the thymus, thymus cell lymphocytes or ''T cells'' mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. ...
. However, histologically, they are more easily identified in the medulla. These cells contain secretory granules which are thought to contain the thymic hormones.
There are six different types: Types 1-3 are in the cortex, and types 4-6 are in the medulla.
Epithelial reticular cells are the primary cell involved with making sure that no
T cell
A T cell is a type of lymphocyte. T cells are one of the important white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell ...
s are allowed to survive which could attack the body's own cells. It does this by expressing a very large proportion of its genome, and expressing as many 'self' proteins on its cell membrane as possible. As the T cells migrate from the cortex of the thymus to the medulla, they come into contact with many epithelial reticular cells, and if they recognise self proteins as a pathogen, then the epithelial cells destroy them.
See also
*
Thymic nurse cell Thymic nurse cells (TNCs) are large epithelial cells found in the cortex of the thymus and also in cortico-medullary junction.Ritter, M. A., C. A. Sauvage, and S. F. Cotmore. "The human thymus microenvironment: in vivo identification of thymic nurs ...
References
External links
*
Description at umdnj.edu* - "Thymus"
* {{UIUCHistologySubject, 416
Immunology
Epithelial cells