Hassall's corpuscles
Encyclopedia
Hassall's corpuscles are structures found in the medulla of the human thymus
, formed from eosinophilic
dead type VI epithelial reticular cells arranged concentrically. They are named for Arthur Hill Hassall
, who discovered them in 1849.
The function of Hassall's corpuscles is currently unclear, and the absence of this structure in the murine thymus has restricted mechanistic dissection. It is known that Hassall's corpuscles are a potent source of the cytokine
TSLP
. In vitro, TSLP directs the maturation of dendritic cells, and increases the ability of dendritic cells to convert naive thymocytes to a Foxp3+ regulatory T cell lineage. It is unknown if this is the physiological function of Hassall's corpuscles in vivo.
Hassall's corpuscles vary in size with diameters from 20 to more than 100μm, and tend to grow larger with age.
Thymus
The thymus is a specialized organ of the immune system. The thymus produces and "educates" T-lymphocytes , which are critical cells of the adaptive immune system....
, formed from eosinophilic
Eosinophilic
Eosinophilic refers to the staining of certain tissues, cells, or organelles after they have been washed with eosin, a dye.Eosin is an acidic dye; thus, the structure being stained is basic....
dead type VI epithelial reticular cells arranged concentrically. They are named for Arthur Hill Hassall
Arthur Hill Hassall
Arthur Hill Hassall was a British physician, chemist and microscopist who is primarily known for his work in public health and food safety....
, who discovered them in 1849.
The function of Hassall's corpuscles is currently unclear, and the absence of this structure in the murine thymus has restricted mechanistic dissection. It is known that Hassall's corpuscles are a potent source of the cytokine
Cytokine
Cytokines are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication...
TSLP
TSLP
Thymic stromal lymphopoietin is a protein belonging to the cytokine family. It is known to play an important role in the maturation of T cell populations through activation of antigen presenting cells....
. In vitro, TSLP directs the maturation of dendritic cells, and increases the ability of dendritic cells to convert naive thymocytes to a Foxp3+ regulatory T cell lineage. It is unknown if this is the physiological function of Hassall's corpuscles in vivo.
Hassall's corpuscles vary in size with diameters from 20 to more than 100μm, and tend to grow larger with age.