Biomaterial Database

[Analysis of Fas antigen gene expression in human thymocytes fractionated with discontinuous gradients using bovine serum albumin]. 1994

M Nakanishi

Department of Pediatrics, Hokkaido University School of Medicine, Sapporo, Japan.

Premature thymocytes proliferate and differentiate from immature to mature T lymphocytes through out both positive and negative selections in thymus. The clonal deletion is a major mechanism of cell selection and mainly depends on apoptosis. Recently, Itoh et al. isolated cDNAs encoding Fas antigen which mediate apoptosis and is expressed on mouse thymocytes. Herein, I further attempted to examine the expression of Fas antigen gene in human thymocytes from thymus resected at cardiac operations. Human thymocytes were separated into 5 fractions with discontinuous gradient using bovine serum albumin (BSA). They consisted of fractions I (BSA concentrations: 10-14%), II (14-16%), III (16-18%), IV (18-20%), and V (20-24%). Human thymocytes in each fraction were characterized regarding the rearrangement of T cell receptor (TCR) genes and the expression of human Fas antigen gene. Human thymocytes were divided into three sub populations according to their stages of differentiation and maturation. First population, thymocytes contained in fraction I, expressed interleukin 2 receptor alpha-chain (IL-2R alpha) and proliferated without the presence of recombinant IL-2 (rIL-2). Second, thymocytes contained in fraction II and III, expressed IL-2R alpha but could not proliferate without the presence of rIL-2. Third, thymocytes contained in fraction IV and V, could not express IL-2R alpha nor proliferate under any conditions assayed, and occupied over 90% of total human thymocytes in number. The southern blot analysis of T cell receptor beta-chain gene constant region (C beta) showed that C beta were rearranged in most of all thymocytes except for small population contained in fraction I. The reverse transcription-polymerase chain reaction (RT-PCR) analysis of Fas antigen gene expression revealed that the thymocytes in fraction I expressed Fas antigen gene more than those in any other fractions and that the thymocytes in fraction V expressed no Fas antigen gene. These results suggested that Fas antigen plays a minor role in the clonal deletion of postnatal human thymocytes.

UI	MeSH Term	Description	Entries
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
D002458	Cell Fractionation	Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.	Cell Fractionations,Fractionation, Cell,Fractionations, Cell
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
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
D000954	Antigens, Surface	Antigens on surfaces of cells, including infectious or foreign cells or viruses. They are usually protein-containing groups on cell membranes or walls and may be isolated.	Cell Surface Antigens,Surface Antigens,Surface Markers, Immunological,Cell Surface Antigen,Immunologic Surface Markers,Markers, Immunological Surface,Surface Antigen,Surface Markers, Immunologic,Antigen, Cell Surface,Antigen, Surface,Antigens, Cell Surface,Immunological Surface Markers,Markers, Immunologic Surface,Surface Antigen, Cell,Surface Antigens, Cell
D012710	Serum Albumin, Bovine	Serum albumin from cows, commonly used in in vitro biological studies. (From Stedman, 25th ed)	Fetal Bovine Serum,Fetal Calf Serum,Albumin Bovine,Bovine Albumin,Bovine Serum Albumin,Albumin, Bovine,Albumin, Bovine Serum,Bovine Serum, Fetal,Bovine, Albumin,Calf Serum, Fetal,Serum, Fetal Bovine,Serum, Fetal Calf
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
D015321	Gene Rearrangement	The ordered rearrangement of gene regions by DNA recombination such as that which occurs normally during development.	DNA Rearrangement,DNA Rearrangements,Gene Rearrangements,Rearrangement, DNA,Rearrangement, Gene,Rearrangements, DNA,Rearrangements, Gene
D015870	Gene Expression	The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.	Expression, Gene,Expressions, Gene,Gene Expressions