Biomaterial Database

Feedback regulation of T cell development in the thymus. 1996

R Mehr, and A S Perelson, and M Fridkis-Hareli, and A Globerson

Theoretical Division, Los Alamos National Laboratory, NM 87545, USA. ramit@t10.lanl.gov

Recent findings suggest that mature T cells in the thymus may regulate the growth and differentiation of immature thymocytes. Here we use mathematical modeling and computer simulations to identify the thymocyte subsets that might serve as targets for regulation, and the processes that might be affected by regulation. Our results suggest that thymocyte development is subject to regulation through two feedback loops: mature CD4+ T cells exert a positive feedback on the single positive CD4+8- thymocyte compartment, by reducing CD4+8- cell death and possibly accelerating the differentiation of CD4+8+ thymocytes into CD4+8- thymocytes; they may also exert a negative feedback on the double-positive CD4+8+ thymocyte compartment, by reducing the proliferation or accelerating the maturation of these cells.

UI	MeSH Term	Description	Entries
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D002455	Cell Division	The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.	M Phase,Cell Division Phase,Cell Divisions,Division Phase, Cell,Division, Cell,Divisions, Cell,M Phases,Phase, Cell Division,Phase, M,Phases, M
D003198	Computer Simulation	Computer-based representation of physical systems and phenomena such as chemical processes.	Computational Modeling,Computational Modelling,Computer Models,In silico Modeling,In silico Models,In silico Simulation,Models, Computer,Computerized Models,Computer Model,Computer Simulations,Computerized Model,In silico Model,Model, Computer,Model, Computerized,Model, In silico,Modeling, Computational,Modeling, In silico,Modelling, Computational,Simulation, Computer,Simulation, In silico,Simulations, Computer
D005246	Feedback	A mechanism of communication within a system in that the input signal generates an output response which returns to influence the continued activity or productivity of that system.	Feedbacks
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013601	T-Lymphocytes	Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.	T Cell,T Lymphocyte,T-Cells,Thymus-Dependent Lymphocytes,Cell, T,Cells, T,Lymphocyte, T,Lymphocyte, Thymus-Dependent,Lymphocytes, T,Lymphocytes, Thymus-Dependent,T Cells,T Lymphocytes,T-Cell,T-Lymphocyte,Thymus Dependent Lymphocytes,Thymus-Dependent Lymphocyte
D013950	Thymus Gland	A single, unpaired primary lymphoid organ situated in the MEDIASTINUM, extending superiorly into the neck to the lower edge of the THYROID GLAND and inferiorly to the fourth costal cartilage. It is necessary for normal development of immunologic function early in life. By puberty, it begins to involute and much of the tissue is replaced by fat.	Thymus,Gland, Thymus,Glands, Thymus,Thymus Glands
D015496	CD4-Positive T-Lymphocytes	A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.	T4 Cells,T4 Lymphocytes,CD4-Positive Lymphocytes,CD4 Positive T Lymphocytes,CD4-Positive Lymphocyte,CD4-Positive T-Lymphocyte,Lymphocyte, CD4-Positive,Lymphocytes, CD4-Positive,T-Lymphocyte, CD4-Positive,T-Lymphocytes, CD4-Positive,T4 Cell,T4 Lymphocyte
D018414	CD8-Positive T-Lymphocytes	A critical subpopulation of regulatory T-lymphocytes involved in MHC Class I-restricted interactions. They include both cytotoxic T-lymphocytes (T-LYMPHOCYTES, CYTOTOXIC) and CD8+ suppressor T-lymphocytes.	Suppressor T-Lymphocytes, CD8-Positive,T8 Cells,T8 Lymphocytes,CD8-Positive Lymphocytes,Suppressor T-Cells, CD8-Positive,CD8 Positive Lymphocytes,CD8 Positive T Lymphocytes,CD8-Positive Lymphocyte,CD8-Positive Suppressor T-Cell,CD8-Positive Suppressor T-Cells,CD8-Positive Suppressor T-Lymphocyte,CD8-Positive Suppressor T-Lymphocytes,CD8-Positive T-Lymphocyte,Cell, T8,Cells, T8,Lymphocyte, CD8-Positive,Lymphocyte, T8,Lymphocytes, CD8-Positive,Lymphocytes, T8,Suppressor T Cells, CD8 Positive,Suppressor T Lymphocytes, CD8 Positive,Suppressor T-Cell, CD8-Positive,Suppressor T-Lymphocyte, CD8-Positive,T-Cell, CD8-Positive Suppressor,T-Cells, CD8-Positive Suppressor,T-Lymphocyte, CD8-Positive,T-Lymphocyte, CD8-Positive Suppressor,T-Lymphocytes, CD8-Positive,T-Lymphocytes, CD8-Positive Suppressor,T8 Cell,T8 Lymphocyte
D018448	Models, Immunological	Theoretical representations that simulate the behavior or activity of immune system, processes, or phenomena. They include the use of mathematical equations, computers, and other electrical equipment.	Immunological Models,Immunologic Model,Model, Immunologic,Immunologic Models,Immunological Model,Model, Immunological,Models, Immunologic