Biomaterial Database

MHC class I antigens, immune surveillance, and tumor immune escape. 2003

Angel Garcia-Lora, and Ignacio Algarra, and Federico Garrido

Servicio de Análisis Clínicos, Hospital Universitario Virgen de las Nieves, Universidad de Granada, Spain.

Oncogenic transformation in human and experimental animals is not necessarily followed by the appearance of a tumor mass. The immune system of the host can recognize tumor antigens by the presentation of small antigenic peptides to the receptor of cytotoxic T-lymphocytes (CTLs) and reject the nascent tumor. However, cancer cells can sometimes escape these specific T-cell immune responses in the course of somatic (genetic and phenotypic) clonal evolution. Among the tumor immune escape mechanisms described to date, the alterations in the expression of major histocompatibility complex (MHC) molecules play a crucial step in tumor development due to the role of MHC antigens in antigen presentation to T-lymphocytes and the regulation of natural killer cell (NK) cell function. In this work, we have (1) updated information on the mechanisms that allow CTLs to recognize tumor antigens after antigen processing by transformed cells, (2) described the altered MHC class I phenotypes that are commonly found in human tumors, (3) summarized the molecular mechanisms responsible for MHC class I alteration in human tumors, (4) provided evidence that these altered human leukocyte antigens (HLA) class I phenotypes are detectable as result of a T-cell immunoselection of HLA class I-deficient variants by an immunecompetent host, and (5) presented data indicating the MHC class I phenotype and the immunogenicity of experimental metastatic tumors change drastically when tumors develop in immunodeficient mice.

UI	MeSH Term	Description	Entries
D007157	Immunologic Surveillance	The theory that T-cells monitor cell surfaces and detect structural changes in the plasma membrane and/or surface antigens of virally or neoplastically transformed cells.	Surveillance, Immunologic,Immunological Surveillance,Immunologic Surveillances,Immunological Surveillances,Surveillance, Immunological,Surveillances, Immunologic,Surveillances, Immunological
D007694	Killer Cells, Natural	Bone marrow-derived lymphocytes that possess cytotoxic properties, classically directed against transformed and virus-infected cells. Unlike T CELLS; and B CELLS; NK CELLS are not antigen specific. The cytotoxicity of natural killer cells is determined by the collective signaling of an array of inhibitory and stimulatory CELL SURFACE RECEPTORS. A subset of T-LYMPHOCYTES referred to as NATURAL KILLER T CELLS shares some of the properties of this cell type.	NK Cells,Natural Killer Cells,Cell, NK,Cell, Natural Killer,Cells, NK,Cells, Natural Killer,Killer Cell, Natural,NK Cell,Natural Killer Cell
D009369	Neoplasms	New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.	Benign Neoplasm,Cancer,Malignant Neoplasm,Tumor,Tumors,Benign Neoplasms,Malignancy,Malignant Neoplasms,Neoplasia,Neoplasm,Neoplasms, Benign,Cancers,Malignancies,Neoplasias,Neoplasm, Benign,Neoplasm, Malignant,Neoplasms, Malignant
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
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
D013602	T-Lymphocytes, Cytotoxic	Immunized T-lymphocytes which can directly destroy appropriate target cells. These cytotoxic lymphocytes may be generated in vitro in mixed lymphocyte cultures (MLC), in vivo during a graft-versus-host (GVH) reaction, or after immunization with an allograft, tumor cell or virally transformed or chemically modified target cell. The lytic phenomenon is sometimes referred to as cell-mediated lympholysis (CML). These CD8-positive cells are distinct from NATURAL KILLER CELLS and NATURAL KILLER T-CELLS. There are two effector phenotypes: TC1 and TC2.	Cell-Mediated Lympholytic Cells,Cytotoxic T Cells,Cytotoxic T Lymphocyte,Cytotoxic T-Lymphocytes,TC1 Cell,TC1 Cells,TC2 Cell,TC2 Cells,Cell Mediated Lympholytic Cells,Cell, Cell-Mediated Lympholytic,Cell, TC1,Cell, TC2,Cell-Mediated Lympholytic Cell,Cytotoxic T Cell,Cytotoxic T Lymphocytes,Cytotoxic T-Lymphocyte,Lymphocyte, Cytotoxic T,Lympholytic Cell, Cell-Mediated,Lympholytic Cells, Cell-Mediated,T Cell, Cytotoxic,T Lymphocyte, Cytotoxic,T Lymphocytes, Cytotoxic,T-Lymphocyte, Cytotoxic
D015395	Histocompatibility Antigens Class I	Membrane glycoproteins consisting of an alpha subunit and a BETA 2-MICROGLOBULIN beta subunit. In humans, highly polymorphic genes on CHROMOSOME 6 encode the alpha subunits of class I antigens and play an important role in determining the serological specificity of the surface antigen. Class I antigens are found on most nucleated cells and are generally detected by their reactivity with alloantisera. These antigens are recognized during GRAFT REJECTION and restrict cell-mediated lysis of virus-infected cells.	Class I Antigen,Class I Antigens,Class I Histocompatibility Antigen,Class I MHC Protein,Class I Major Histocompatibility Antigen,MHC Class I Molecule,MHC-I Peptide,Class I Histocompatibility Antigens,Class I Human Antigens,Class I MHC Proteins,Class I Major Histocompatibility Antigens,Class I Major Histocompatibility Molecules,Human Class I Antigens,MHC Class I Molecules,MHC-I Molecules,MHC-I Peptides,Antigen, Class I,Antigens, Class I,I Antigen, Class,MHC I Molecules,MHC I Peptide,MHC I Peptides,Molecules, MHC-I,Peptide, MHC-I,Peptides, MHC-I
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus
D017951	Antigen Presentation	The process by which antigen is presented to lymphocytes in a form they can recognize. This is performed by antigen presenting cells (APCs). Some antigens require processing before they can be recognized. Antigen processing consists of ingestion and partial digestion of the antigen by the APC, followed by presentation of fragments on the cell surface. (From Rosen et al., Dictionary of Immunology, 1989)	Antigen Processing,Antigen Presentations,Antigen Processings