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 ?
Anaphylatoxin C5a receptor mRNA is strongly expressed in Kupffer and stellate cells and weakly in sinusoidal endothelial cells but not in hepatocytes of normal rat liver.
ASP is identical to C3adesArg, the inactive fragment of the complement anaphylatoxin peptide, C3a.
Furthermore, complement activation may potentiate platelet function (29, 30), as platelet activation and aggregation are directly induced by the anaphylatoxin complement C3a and its derivatives, which are activation products of complement C3 (31, 32).
Anaphylatoxin C5a modulates hepatic stellate cell migration.
In patients with RA, complexes of antibodies containing rheumatoid factor form in the blood like iles flottant; they become trapped in joint spaces, joint cells try to get rid of the unwanted debris, cry havoc, and let loose the dogs of inflammation: anaphylatoxins C3a, C5a, and eicosanoids, etc.
Characterization of complement anaphylatoxins and their biological responses.
Evolution of anaphylatoxins, their diversity and novel roles in innate immunity: Insights from the study of fish complement (Review).
A similarly comprehensive and well-written review covers the anaphylatoxins, their receptors, and potential therapeutic drugs that may affect these biological activities.
Similarities between the anaphylatoxins and the oyster/mud crab/cyanobacteria peptides suggest that there may be homology among their respective receptors.
9]), anaphylatoxins (C3a, C4a, and C5a), and fibrinopeptides A and B (19).
Chenoweth DE Cooper SW, Hugli TE, Stewart RW, Blackstone EH, Kirklin JW: Complement activation during cardiopulmonary bypass; evidence for generation of C3 a and C5 anaphylatoxins.