anaphylatoxin

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anaphylatoxin

 [an″ah-fil´ah-tok″sin]
a substance produced by complement activation that causes the release of histamine and other mediators of immediate hypersensitivity from basophils and mast cells, thereby producing signs and symptoms of immediate hypersensitivity (anaphylaxis) without involvement of IgE.

an·a·phyl·a·tox·in

(an'ă-fil-ă-tok'sin),
Low molecular weight cleavage products (C3a, C4a, and C5a); generated by the activation of the complement cascade. They are proinflammatory; can cause permeability, smooth muscle contraction, and mask cell degranulation.
Synonym(s): anaphylotoxin
[anaphylaxis + toxin]

anaphylatoxin

/ana·phyl·a·tox·in/ (-fil´ah-tok″sin) a substance produced in blood serum during complement fixation which serves as a mediator of inflammation by inducing mast cell degranulation and histamine release; on injection into animals, it causes anaphylactic shock.

anaphylatoxin

[an′əfī′lətok′sin]
a fragment (C3a, C4a, or C5a) that is produced during the pathways of the complement system. Along with other mechanisms, it mediates changes in mast cells leading to the release of histamine and other immunoreactive or inflammatory reactive substances. If the degranulation of mast cells is too strong, it can cause allergic reactions.

anaphylatoxin

(1) Any antigen that reacts with an IgE and precipitates an anaphylactic reaction by stimulating histamine release.
(2) Activated complement fragments (C3a, C4a and C5a) that bind to mast cells and basophils and trigger the release of inflammatory mediators.

an·a·phyl·a·tox·in

, anaphylotoxin (an'ă-fil'ă-tok'sin, an'ă-fil'ō-tok'sin)
1. A substance postulated to be the immediate cause of anaphylactic shock and that is assumed to result from the in vivo combination of specific antibody and the specific sensitizing material.
2. The small fragment (C3a) split from the third component (C3) of complement, which produces a local wheal following intracutaneous injection.

anaphylatoxin

Any substance that can directly cause degranulation of MAST CELLS thereby bringing about an acute allergic reaction.

anaphylatoxin

a substance produced in blood serum when complement is activated; serves as a mediator of inflammation by inducing mast cell degranulation, histamine release and increased vascular permeability, and on injection into animals, it causes anaphylactic shock.

anaphylatoxin inhibitor
a specific serum carboxypeptidase, one of the complement proteins.
References in periodicals archive ?
We now appreciate that cytokines, such as TNF alpha and IL-1, are important mediators of inflammation in RA, (14) but in the joint they act downstream of the primary insults: immune complexes and anaphylatoxins.
C3a and C5a anaphylatoxins circulate during exacerbations of disease.
Complement is activated within the synovial fluid, and the most important complement components in the fluid are the C3a and C5a anaphylatoxins.
Most would agree that complexes of 7s IgG or 19s IgM rheumatoid factors directed against altered 7s IgGs--of self-assembling 7s IgGs (Mannik) activate anaphylatoxins in the joint.
The cells of innate immunity, the phagocytes or eating cells were first described in starfish by Elie Metchnikoff in 1883, and the active humors of adaptive immunity the anaphylatoxins, were described by Charles Richet in 1901.
BC3 was subsequently determined to be the anaphylatoxin C3a lacking the C-terminal arginine (C3adesA,.
Products derived from the activation of complement components include important non-selfrecognition molecules C3b, C4b, and C5b as well as the anaphylatoxins C3a, C4a, and C5a, which induce a variety of cellular immune responses (3-8).
Futhan effectively stabilizes freshly drawn blood samples from healthy individuals, permitting direct measurement of the anaphylatoxins C3a and C4a (39).
Elevated plasma levels of the anaphylatoxins C3a and C4a are associated with fatal outcome in sepsis.
1]-Esterase inhibitor Decreased because of activation of complement cascade Anaphylatoxins Increased because of complement ([C.
9]), anaphylatoxins (C3a, C4a, and C5a), and fibrinopeptides A and B (19).