Normal structure, function and histology of the thymus.
The thymus, a primary lymphoid organ and the initial site for development of T cell immunological function, is morphologically similar across species. It is actually an epithelial organ in which its epithelial cells provide a framework containing T cells as well as smaller numbers of other lymphoid cells. A symbiotic interaction exists between the thymic microenvironment and developing T cells, and the specificity of T cell release into the systemic circulation is under thymic control. The thymic cortex in a young animal is heavily populated by developing T cells along with a smaller proportion of associated epithelial cells. Larger, more mature T cells are found in the medulla where epithelial and other cell types are more abundant. Understanding normal morphological features of the thymus and their perturbations provides a cornerstone to assessing immune system function.
Pearse
Gail
G
AstraZeneca, Alderley Park, Macclesfield, Cheshire SK10 4TG, United Kingdom. Gail.Pearse@astrazeneca.com
D000818:Animals; D051379:Mice; D016513:Mice, SCID; D051381:Rats; D013601:T-Lymphocytes / Q000166:cytology / Q000502:physiology; D013950:Thymus Gland / Q000033:anatomy & histology* / Q000502:physiology*