Biomaterial Database

T cell receptor-negative thymocytes from SCID mice can be induced to enter the CD4/CD8 differentiation pathway. 1990

E W Shores, and S O Sharrow, and I Uppenkamp, and A Singer

Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.

In order to investigate the role of T cell receptor (TcR) expression in thymocyte maturation, we have analyzed thymocytes from C.B-17/SCID mice, which are unable to productively rearrange their antigen receptor genes and fail to express TcR. Despite this defect, SCID thymocytes are functional as they produce lymphokines and proliferate in response to a variety of stimuli. Phenotypic analysis revealed that thymocyte populations from young adult SCID mice resemble thymocyte populations from normal embryonic mice in that they are large, Thy-1.2+, CD4-, CD8-, TcR- and enriched in CD5lo, IL2R+ and Pgp1+ cells. However, other TcR- populations normally present in adult mice (i.e., CD4-CD8+ cells and CD4+CD8+ cells) are absent from the thymus of TcR- adult SCID mice. To understand the basis of the developmental arrest of TcR- SCID thymocytes at the CD4-CD8- stage of differentiation, we analyzed thymi from the occasional "leaky" SCID mouse which possesses small numbers of TcR+ thymocytes. We found that the presence of TcR+ cells within a SCID thymus was invariably associated with the presence of CD4+ and/or CD8+ SCID thymocytes. Interestingly, however, the CD4+/CD8+ SCID thymocytes were not themselves necessarily TcR+. That is, emergence of SCID thymocytes expressing CD4/CD8 was tightly linked to the presence of TcR+ cells within that SCID thymus, but the SCID thymocytes that expressed CD4/CD8 were not necessarily the same cells that expressed TcR. Finally, we found that the introduction into TcR- SCID mice of normal bone marrow cells that give rise to TcR+ cells within the SCID thymus promoted the differentiation of SCID thymocytes into CD4-CD8+ and CD4+CD8+ TcR- cells. These data indicate that TcR+ cells within the thymic milieu provide critical signals which promote entry of CD4-CD8-TcR- precursor T cells into the CD4/CD8 differentiation pathway. When applied to differentiation of normal thymocytes, these findings may imply a critical role for early appearing CD4-CD8- TcR (gamma/delta)+ cells in initiating normal thymic ontogeny.

UI	MeSH Term	Description	Entries
D007153	Immunologic Deficiency Syndromes	Syndromes in which there is a deficiency or defect in the mechanisms of immunity, either cellular or humoral.	Antibody Deficiency Syndrome,Deficiency Syndrome, Immunologic,Deficiency Syndromes, Antibody,Deficiency Syndromes, Immunologic,Immunologic Deficiency Syndrome,Immunological Deficiency Syndromes,Antibody Deficiency Syndromes,Deficiency Syndrome, Antibody,Deficiency Syndrome, Immunological,Deficiency Syndromes, Immunological,Immunological Deficiency Syndrome,Syndrome, Antibody Deficiency,Syndrome, Immunologic Deficiency,Syndrome, Immunological Deficiency,Syndromes, Antibody Deficiency,Syndromes, Immunologic Deficiency,Syndromes, Immunological Deficiency
D008222	Lymphokines	Soluble protein factors generated by activated lymphocytes that affect other cells, primarily those involved in cellular immunity.	Lymphocyte Mediators,Mediators, Lymphocyte
D008817	Mice, Mutant Strains	Mice bearing mutant genes which are phenotypically expressed in the animals.	Mouse, Mutant Strain,Mutant Mouse Strain,Mutant Strain of Mouse,Mutant Strains of Mice,Mice Mutant Strain,Mice Mutant Strains,Mouse Mutant Strain,Mouse Mutant Strains,Mouse Strain, Mutant,Mouse Strains, Mutant,Mutant Mouse Strains,Mutant Strain Mouse,Mutant Strains Mice,Strain Mouse, Mutant,Strain, Mutant Mouse,Strains Mice, Mutant,Strains, Mutant Mouse
D011948	Receptors, Antigen, T-Cell	Molecules on the surface of T-lymphocytes that recognize and combine with antigens. The receptors are non-covalently associated with a complex of several polypeptides collectively called CD3 antigens (CD3 COMPLEX). Recognition of foreign antigen and the major histocompatibility complex is accomplished by a single heterodimeric antigen-receptor structure, composed of either alpha-beta (RECEPTORS, ANTIGEN, T-CELL, ALPHA-BETA) or gamma-delta (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA) chains.	Antigen Receptors, T-Cell,T-Cell Receptors,Receptors, T-Cell Antigen,T-Cell Antigen Receptor,T-Cell Receptor,Antigen Receptor, T-Cell,Antigen Receptors, T Cell,Receptor, T-Cell,Receptor, T-Cell Antigen,Receptors, T Cell Antigen,Receptors, T-Cell,T Cell Antigen Receptor,T Cell Receptor,T Cell Receptors,T-Cell Antigen Receptors
D002454	Cell Differentiation	Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.	Differentiation, Cell,Cell Differentiations,Differentiations, Cell
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
D005434	Flow Cytometry	Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.	Cytofluorometry, Flow,Cytometry, Flow,Flow Microfluorimetry,Fluorescence-Activated Cell Sorting,Microfluorometry, Flow,Cell Sorting, Fluorescence-Activated,Cell Sortings, Fluorescence-Activated,Cytofluorometries, Flow,Cytometries, Flow,Flow Cytofluorometries,Flow Cytofluorometry,Flow Cytometries,Flow Microfluorometries,Flow Microfluorometry,Fluorescence Activated Cell Sorting,Fluorescence-Activated Cell Sortings,Microfluorimetry, Flow,Microfluorometries, Flow,Sorting, Fluorescence-Activated Cell,Sortings, Fluorescence-Activated Cell
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000945	Antigens, Differentiation, T-Lymphocyte	Antigens expressed on the cell membrane of T-lymphocytes during differentiation, activation, and normal and neoplastic transformation. Their phenotypic characterization is important in differential diagnosis and studies of thymic ontogeny and T-cell function.	Antigens, Differentiation, T-Cell,Differentiation Antigens, T-Cell,L3T4 Antigens,Leu Antigens, T-Lymphocyte,T-Cell Differentiation Antigens,T-Lymphocyte Differentiation Antigens,T6 Antigens,Antigens, Differentiation, T Lymphocyte,Differentiation Antigens, T Lymphocyte,Antigens, L3T4,Antigens, T-Cell Differentiation,Antigens, T-Lymphocyte Differentiation,Antigens, T-Lymphocyte Leu,Antigens, T6,Differentiation Antigens, T Cell,Differentiation Antigens, T-Lymphocyte,Leu Antigens, T Lymphocyte,T Cell Differentiation Antigens,T Lymphocyte Differentiation Antigens,T-Lymphocyte Leu Antigens
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