Hassall corpuscles
Hassall corpuscles (lat. Corpuscula thymi ) are round, layered agglomerations of several thymus epithelial cells in a normal thymus . They are particularly found in the thymus medulla. The thymus epithelial cells show signs of degeneration and cell death in the center of the Hassall corpuscle. They arise from the ectoderm during embryonic development and undergo a cell differentiation similar to that of cells in the epidermis ; keratin and preceratin could therefore be detected in them.
The function of Hassall corpuscles is unclear, and their presence and morphology vary widely between species; for example, they are not present in the thymus tissue of mice. Their number increases until puberty , after which they disappear with the breakdown of the thymus into the retrosternal fat body . They can calcify or cystically degenerate inside. They may play a role in the removal of apoptotic thymocytes or in the maturation of T lymphocytes because they contain the cytokine TSLP ( thymic stromal lymphopoietin ).
The Hassall bodies are named after their discoverer, the English doctor, microbiologist and chemist Arthur Hill Hassall , who first described them in 1846.
swell
- Alfred Benninghoff (ed.): Macroscopic and microscopic anatomy of humans , 14th edition 1985, volume 2, p. 644 ISBN 3-541-00252-2
Individual evidence
- ^ B. von Gaudecker B and EM Schmale: Similarities between Hassall's corpuscles of the human thymus and the epidermis. An investigation by electron microscopy and histochemistry . Cell Tissue Res. (1974) 151 (3): pp. 347-368 PMID 4426075
- ↑ N. Watanabe et al .: Hassall's corpuscles instruct dendritic cells to induce CD4 + CD25 + regulatory T cells in human thymus . Nature (2005) 436 (7054): pp. 1181-1185 PMID 16121185
- ↑ M. Raica et al .: Structural heterogeneity and immunohistochemical profile of Hassall corpuscles in normal human thymus . Ann. Anatomy (2006) 188 (4): pp. 345-352 PMID 16856599
- ↑ Louis Kater: A Note on Hassall's Corpuscles. Contemporary Topics in Immunobiology Volume 2, 1973, pp. 101-109.
- ^ Hassall, AH, 1846. Microscopic Anatomy of the Human Body in Health and Disease, Highly, London.