What are anergic cells?
Abstract. T cell anergy is a tolerance mechanism in which the lymphocyte is intrinsically functionally inactivated following an antigen encounter, but remains alive for an extended period of time in a hyporesponsive state.
What is costimulation immunology?
From Wikipedia, the free encyclopedia. Co-stimulation is a secondary signal which immune cells rely on to activate an immune response in the presence of an antigen-presenting cell. In the case of T cells, two stimuli are required to fully activate their immune response.
What is clonal ignorance?
Clonal ignorance theory, according to which autoreactive T cells that are not represented in the thymus will mature and migrate to the periphery, where they will not encounter the appropriate antigen because it is inaccessible tissues.
What is meant by the clonal selection hypothesis?
Clonal selection theory is a scientific theory in immunology that explains the functions of cells of the immune system (lymphocytes) in response to specific antigens invading the body. In short, the theory is an explanation of the mechanism for the generation of diversity of antibody specificity.
What does Anergic mean in psychology?
absence of energy
1. absence of energy. 2. a state of passivity. Also called anergy.
What is meant by costimulation?
Co-stimulation: An event in the immune system involving the delivery of a second signal by an antigen-presenting cell. The second signal rescues the activated T cell from anergy (which is a state of immune unresponsiveness), allowing the T cell to produce the lymphokines necessary for the growth of additional T cells.
What is the purpose of costimulation?
Co-stimulatory molecules are a heterogenous group of cell surface molecules that act to amplify or counteract the initial activating signals provided to T cells from the T cell receptor (TCR) following its interaction with an antigen/major histocompatibility complex (MHC), thereby influencing T cell differentiation and …
What is an example of clonal selection?
Clonal selection theory of lymphocytes: 1) A hematopoietic stem cell undergoes differentiation and genetic rearrangement to produce 2) immature lymphocytes with many different antigen receptors. Those that bind to 3) antigens from the body’s own tissues are destroyed, while the rest mature into 4) inactive lymphocytes.