Biomaterial Database

Lymphocyte differentiation and major histocompatibility complex antigen expression in the embryonic thymus. 1980

E J Jenkinson, and J J Owen, and R Aspinall

During embryogenesis, stem cells migrate from the bloodstream into the thymic rudiment where they proliferate and differentiate into T lymphocytes. The epithelial cells of the thymic stroma may influence these processes by providing hormonal and/or contact stimuli to the developing lymphoblasts. Recently, it has been shown that T cells 'learn' to recognise the major histocompatability complex (MHC) antigens during thymic lymphopoiesis and become MHC-restricted. Their subsequent response to other antigens can only occur in the context of MHC antigens of the haplotype encountered in the thymus. Little is known, however, of antigen expression on the thymic stroma which may provide the reference framework on which this MHC restriction is based. In this study we use monoclonal antibodies to show that antigens of the K and I regions of the MHC are detectable on cells of the embryonic mouse thymic stroma from around the 14th day of gestation, just when lymphocyte differentiation is commencing. Furthermore, I-region antigen (Ia antigen) expression is probably limited to thymic epithelium at this stage of gestation and we have not detected Ia on other epithelial tissues of the pharyngeal complex. This pattern of expression is consistent with a role for the thymic stroma in MHC restriction, perhaps by the selection of lymphoid cells for survival on the basis of their recognition of stromal MHC determinants.

UI	MeSH Term	Description	Entries
D007519	Isoantigens	Antigens that exist in alternative (allelic) forms in a single species. When an isoantigen is encountered by species members who lack it, an immune response is induced. Typical isoantigens are the BLOOD GROUP ANTIGENS.	Alloantigens,Alloantigen,Isoantigen
D008214	Lymphocytes	White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.	Lymphoid Cells,Cell, Lymphoid,Cells, Lymphoid,Lymphocyte,Lymphoid Cell
D008285	Major Histocompatibility Complex	The genetic region which contains the loci of genes which determine the structure of the serologically defined (SD) and lymphocyte-defined (LD) TRANSPLANTATION ANTIGENS, genes which control the structure of the IMMUNE RESPONSE-ASSOCIATED ANTIGENS, HUMAN; the IMMUNE RESPONSE GENES which control the ability of an animal to respond immunologically to antigenic stimuli, and genes which determine the structure and/or level of the first four components of complement.	Histocompatibility Complex,Complex, Histocompatibility,Complex, Major Histocompatibility,Complices, Histocompatibility,Complices, Major Histocompatibility,Histocompatibility Complex, Major,Histocompatibility Complices,Histocompatibility Complices, Major,Major Histocompatibility Complices
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
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
D005865	Gestational Age	The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated from the onset of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization. It is also estimated to begin from fertilization, estrus, coitus, or artificial insemination.	Embryologic Age,Fetal Maturity, Chronologic,Chronologic Fetal Maturity,Fetal Age,Maturity, Chronologic Fetal,Age, Embryologic,Age, Fetal,Age, Gestational,Ages, Embryologic,Ages, Fetal,Ages, Gestational,Embryologic Ages,Fetal Ages,Gestational Ages
D006183	H-2 Antigens	The major group of transplantation antigens in the mouse.	H2 Antigens,Antigens, H-2,Antigens, H2,H 2 Antigens
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
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