Biomaterial Database

Expression of an unusual T cell receptor (TCR)-V beta repertoire by Ly-6C+ subpopulations of CD4+ and/or CD8+ thymocytes. Evidence for a developmental relationship between Ly-6C+ thymocytes and CD4-CD8-TCR-alpha beta+ thymocytes. 1991

Y Takahama, and S O Sharrow, and A Singer

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

A novel thymocyte subpopulation expressing an unusual TCR repertoire was identified by high surface expression of the Ly-6C Ag. Ly-6C+ thymocytes were distributed among all four CD4/CD8 thymocyte subsets, and represented a readily identifiable subpopulation within each one. Ly-6C+ thymocytes express TCR-alpha beta, arise late in ontogeny, and appear in the CD4/CD8 developmental pathway after birth in a sequence that resembles that followed by conventional Ly-6C- cells during fetal ontogeny. Most interestingly, adult Ly-6C+ thymocytes express an unusual TCR-V beta repertoire that is identical to that expressed by CD4-CD8-TCR-alpha beta+ thymocytes in its overexpression of TCR-V beta 8 and in its expression of some potentially autoreactive TCR-V beta specificities. This unusual TCR-V beta repertoire was even expressed by Ly-6C+ thymocytes contained within the CD4+ CD8- 'single positive' thymocyte subset. Thus, expression of this unusual TCR-V beta repertoire is not limited to CD4-CD8-thymocytes, and is unlikely to be a consequence of their double negative phenotype. Rather, we think that Ly-6C+TCR-alpha beta+ thymocytes and CD4-CD8-TCR-alpha beta+ are developmentally interrelated, a conclusion supported by several lines of evidence including the selective failure of both Ly-6C+ and CD4-CD8-TCR-alpha beta+ thymocyte subsets to appear in TCR-beta transgenic mice. In contrast, peripheral Ly-6C+ T cells are developmentally distinct from Ly-6C+ thymocytes in that peripheral Ly-6C+ T cells expressed a conventional TCR-V beta repertoire and developed normally in TCR-beta transgenic mice in which Ly-6C+ thymocytes failed to arise. We conclude that: 1) expression of a skewed TCR-V beta repertoire is a characteristic of Ly-6C+TCR-alpha beta+ thymocytes as well as CD4-CD8-TCR-alpha beta+ thymocytes, and is not unique to thymocytes expressing neither CD4 nor CD8 accessory molecules; and 2) Ly-6C+ thymocytes are developmentally linked to CD4-CD8-TCR-alpha beta+ thymocytes, but not to Ly-6C+ peripheral T cells. We suggest that Ly-6C+TCR-alpha beta+ thymocytes are not the developmental precursors of Ly-6C+ peripheral T cells, but rather may be the developmental precursors of CD4-CD8-TCR-alpha beta+ thymocytes.

UI	MeSH Term	Description	Entries
D008822	Mice, Transgenic	Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.	Transgenic Mice,Founder Mice, Transgenic,Mouse, Founder, Transgenic,Mouse, Transgenic,Mice, Transgenic Founder,Transgenic Founder Mice,Transgenic Mouse
D001854	Bone Marrow Cells	Cells contained in the bone marrow including fat cells (see ADIPOCYTES); STROMAL CELLS; MEGAKARYOCYTES; and the immediate precursors of most blood cells.	Bone Marrow Cell,Cell, Bone Marrow,Cells, Bone Marrow,Marrow Cell, Bone,Marrow Cells, Bone
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
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
D000367	Age Factors	Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.	Age Reporting,Age Factor,Factor, Age,Factors, Age
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
D000950	Antigens, Ly	A group of lymphocyte surface antigens located on mouse LYMPHOCYTES. Specific Ly antigens are useful markers for distinguishing subpopulations of lymphocytes.	Ly Antigens
D013154	Spleen	An encapsulated lymphatic organ through which venous blood filters.
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