Hypersensitivities reaginic

IgE <0.0001 Reaginic antibody involved in immediate hypersensitivity antihelminthic does not bind complement... 

IMMEDIATE HYPERSENSITIVITY (Tissue-fixed reaginic antibodyl... 

Fig. 6. Diagram to show how, when allergen becomes bound to mast-cell fixed reaginic antibody (IgE), the vasoactive amines mediating immediate hypersensitivity are discharged. The mast cell is capable of becoming recharged, etc. Excess IgG-antibodies can block the access of allergen, which acts only when bound to two IgE molecules.

Parish WE (1970) Short-term anaphylactic IgG antibodies in human sera. Lancet 2 591-592 Parish WE (1971) Detection of reagin and short-term sensitizing anaphylactic or anaphylactoid antibodies to milk in sera of allergic and normal persons. Clin Allergy 1 369-380 Parker CW, de Week AL, Kern M, Eisen HN (1962 a) The preparation and some properties of penicillenic acid derivatives relevant to penicilhn hypersensitivity. J Exp Med 115 803-819... 

Immunoglobulin E igE 190000 <0.0003 [<100] Antibodies (reagines) Reaginic hypersensitivity reactions Parasitic infestations Non-lgE myeloma Congenital deficit Acquired immunodeficiencies... 

Allergy a hypersensitivity of the immune apparatus s pathological immune reaction induced either by antibodies (immediate hypersensitivity) or by lymphoid cells (delayed type A.). Unlike the delayed type, immediate hypersensitivity can be passively transmitted in the serum. Symptoms of immediate hy-peisensitivity begin shortly after contact and decay rapidly, but delayed type symptoms do not attain a maximum for 24-48 hours then decline slowly over days or weeks Examples of immediate type A. are anaphylaxis the Arthus reaction and serum sickness. The best known A., anaphylaxia, can occur as a local (cutaneous) reaction (e.g. a rash with blisters) or as a systemic reaction (anaphylactic shock). Asthma, hay fever and nettle rashes are also examples of local anaphylactic reactions which are induced by reagins (see Immunoglobulins IgE). Only primates can be sensitized by injection with human reagins. An example of delayed type A. is the tuberculin reaction, which is based on a cellular immune response. 

Type I reactions are those in which antibody is attached to the surface of a mast cell. Contact with antigen in solution results in release of the soluble mediators of anaphylaxis, producing in the skin the typical immediate weal and flare reaction. This commences within minutes of antigen administration, is maximal after 15-20 min, and is usually no longer detectable macroscopically after 1 hour. In humans, most immediate hypersensitivity is produced by antibodies of the IgE-class. However, in many animal species, similar reactions are commonly produced by IgG subclass antibodies. There is also some evidence that immediate-type reactions also can be produced occasionally in humans by non-reaginic IgG subclass antibodies (Parish, 1970). 

Wilkie BN and Nielsen K (1981) Bovine hypersensitivity pneumonitis and reaginic antibody. Adv Exp Med Biol... 

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