Immune response T cells

See also Ribonucleotide Reductase, The Immune Response, T Cells and the Cellular Response... 

HDACll immune response T-cell defects cancer... 

After activation, cytotoxic T cells emerge from lymphoid organs to infiltrate the graft and trigger the immune response. These cells have been shown to induce graft destruction via two mechanisms (1) secretion of the cytotoxic proteins perforin and granzyme B, and (2) induction of cellular apoptosis... 

Homo sapiens (compared to Drosophila melanogaster) Large-scale gene duplications with substantial expansion of genes involved in acquired immune response (B cells, T cells, major histocompatibility complex genes, cytokines, chemokines and their receptors), plasma proteases (complement and hemostatic proteins), proteins associated with apoptotic regulation and proteins related to neuronal network formation and electrical coupling... 

To initiate a T-cell immune response, antigen presenting cells have to display antigenic peptides com-plexed with the major histocompatibility complex (MHC) on their cell surface. The T-cell receptor of CDS cells is specific for the peptide-MHC class I complex while the CD4 cell receptor binds the peptide-MHC class II complex. This binding of the peptide-MHC II complex stimulates CD4 cell proliferation and subsequent lymphokine release. This CD4 cell response can initiate a delayed hypersensitivity reaction. However CD4 activation and the production of various lymphokines is also needed for the generation of cytotoxic T-cells and for the differentiation of plasma cells from B-lymphocytes and the antibody response by these plasma cells. For their role in also the humoral immune response CD4 cells are called T-helper cells. 

IFN-y modulates a number of components of the immune response. This is the only type II IFN whereas there are more than 20 types of type I IFNs (IFN-a, IFN-(3, IFN-w and IFN-t). It is not related to type I IFNs, has separate receptors and is encoded by a different chromosomal locus. IFN-y is produced by activated T lymphocytes (THi and CD8+ cells), NK cells, B cells, NKT cells and professional APCs. It promotes the activity of cytolytic T lymphocytes, macrophages and NK cells. The cell self-activation and activation of nearby cells in part may result from IFN-y production by professional APCs, which include monocyte/macrophage and dendritic cells. The early host defense against infection is likely to utilize IFN-y secreted by NK and professional APCs. In acquired immune responses, T lymphocytes are the major source of IFN-y. 

Cell-mediated immunity Lymphoproliferative response T cell mitogens (Con A and... 

An effect of sublethal exposures (acute, intermediate-term, or chronic) to 2,3,7,8-TCDD common to all species studied is thymic atrophy. Depletion of lymphocytes results in suppression of T-cell immunity. The T-cell responses studied have included delayed hypersensitivity responses, rejection of skin... 

Acquired immunity is immunity that develops with exposme to antigens the immune system builds a defence that is specific to that antigen. B-ceU lymphocytes, produced in the stem cells of the bone marrow, synthesise and release antibody they oversee the humoral immune response. T-ceU lymphocytes, produced in the bone marrow but sensitised in the thymus, are the basis of the ceU-mediated immune response. 

The first line of defense in any injured dssue is the innate immune response, characterized by acdvity of the phagocydc immune cells (Paape et al., 2000), however, this response is dghtly cond olled by adapdve immunity, namely T cells. There are different subpopuladons of CD4+ T cells, each responsible for a certain type of immune response. Thl cells, for example. 

T lymphocyte migration serves to bring the entire range of T lymphocyte receptor specificities in contact with antigen. It also serves to disseminate the products of an immune response, effector cells and memory cells, to... 

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