Akademik

Anergy

A state of immune unresponsiveness. Induced when the T cell's antigen receptor is stimulated, effectively freezing T cell responses pending a "second signal" from the antigen-presenting cell. The delivery of the second signal by the antigen-presenting cell rescues the activated T cell from anergy, allowing it to produce the lymphokines necessary for the growth of additional T cells. T cells are small white blood cells that orchestrate and directly participate in the immune defenses. Also known as T lymphocytes, they are processed in the thymus (which is why they are called T cells).

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1. Absence of ability to generate a sensitivity reaction to substances expected to be antigenic (immunogenic, allergenic) in that individual. 2. Lack of energy. SYN: anergia. [G. an- priv. + energeia, energy, from ergon, work]

- negative a. a reduction of the normal or usual immunologic responses because of unrelated intervening disease. SYN: nonspecific a..

- nonspecific a. SYN: negative a..

- positive a. a reduction of the normal or usual immunologic response resulting from a reaction to a specific allergen. SYN: specific a..

- specific a. SYN: positive a..

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an·er·gy 'an-(.)ər-jē n, pl -gies a condition in which the body fails to react to an injected allergen or antigen (as tuberculin)

an·er·gic -jik adj

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1. lack of response to a specific antigen or allergen.

2. lack of energy.

• anergic adj.

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an·er·gy (anґər-je) 1. lack of energy, extreme passivity. 2. diminished reactivity to all antigens; it may take the form of diminished immediate hypersensitivity, diminished delayed hypersensitivity, or both. Cf. immunologic tolerance.

Medical dictionary. 2011.