An abosolute minimum of 2.8 mL of serum is required for this assay.
The prevalence of systemic reactions to stinging insect allergy has been estimated to be about 2-3%. Allergic sensitization occurs in about 30% of individuals after a sting but usually declines significantly after several years. It is estimated that insect stings kill 40 to 50 people per year in the United States. Death often occurs within the first hour after a sting when systemic anaphylaxis occurs. The relative amount of venom protein deposited with a single sting varies for the different insects: A.mellifera (50-100 mcg) and Vespids (2-10 mcg).
Simplified Taxonomy of the Order Hymenoptera
Superfamily: Apoidea Vespoidea
Family: Apidae Vespidae Formicidae
Subfamily: Apinae Polistinae Vespinae Myrmicinae
Genus: Apis Bombus Polistes Vespula Solenopsis
Dolichovespula (Subgenus)
Species: A. mellifera B. terricola P. annularis V. vulgaris D. arenaria S. invicta
P. fuscatus V. germanica D. maculata S. richteri
Names: Honey Bee Bumble Bee Paper Wasp Yellow Jacket Hornets Imported Fire Ant
In general, the immunologic cross-reactivity tends to follow taxonomic divisions:
1. There is little cross-reaction between the vespids (yellow jackets/hornets) and the Apis mellifera (honey bee).
2. Apis and Bombus cross react extensively.
3. Dolichovespula (white and yellow hornets) and Vespula (yellow jackets) usually have strong cross reactions.
4. The above vespids generally cross react slightly with the Polistes wasps.
Different major compounds of bee venom have been extensively studied. The venom contains several components of a protein nature virtually all of, which are allergenic, especially hyaluronidase and the phospholipases, which have shown reactivity to IgE antibodies from almost all patients with bee sting allergy.
There is minimal crossreactivity between honeybee venom and the major allergen of the Vespidae, called antigen 5 (26).
Crossreactivity & clinical experience - Vespula
A study conducted in Madrid showed that sensitization to Vespula venom is more common than to Polistes but Polistes spp. showed crossreactivity (20). Crossreactivity patterns to other wasp species are not as thoroughly understood as those among Vespidae but some patients apparently paper wasp-sensitive exhibit cross-reactions to other vespid venoms (9). The conclusions drawn from the study stated that the confusion surrounding an individual patient's sensitivity dictates that physicians conducting immunotherapy choose all venoms showing positive sensitivity by RAST or skin prick test. It is hoped that this test will help resolve this difficult clinical situation.
Different major allergens from YJ venom have been isolated and crossreactivities between components of venoms from different wasp species have been identified. Thus, elevated levels of IgE antibodies with affinity to YJ venom have been measured in patients sensitized to the European hornet (i75) and in patients sensitized to the American species, yellow jacket (11).
There is cross-reaction of the hyaluronidases of honeybee and yellow jacket but the phospholipases show minimal crossreaction whereas antigen 5 is restricted to YJ. The differences in clinical reactions to these venoms which crossreact may be related to the differences seen in individual components crossreactivity (26).
Properly administered venom immunotherapy is extremely effective in protecting patients at risk for insect sting anaphylaxis. Venom immunotherapy with 100 ?g maintenance doses of bee or vespid venom has been shown to be 95 ? 97% effective in preventing anaphylactic reactions on subsequent stings. Since the treatment can be expensive and hazardous, patient selection criteria are important and there is a need to know if a patient has multiple venom sensitivity or whether the patient has cross-reacting antibodies.
This test must be carefully interpreted. On one hand it has the potential to falsely reassure patients they will not react to other Hymenoptera, and on the other, it may result in unnecessary immunotherapy. It will be restricted to allergists practising in New Zealand.
References
1 CAP RAST-inhibition Pharmacia Diagnostics document 300512/1.0.
2 Poulsen LK.?In vivo and in vitro techniques to determine the biological activity of food allergens.? Journal of Chromatography B, 756 (2001) 41-55.
http://immuneweb.xxmc.edu.cn/progress/1043.pdf
3 Yman L, Ponterius G, Brandt R.?RAST-based allergen assay methods.? Developments in Biological Standardization. 29:151-65, 1975
4 Aalbers e RC, Kleine Budde I, Stapel SO, van Ree R. ?Structural aspects of cross-reactivity and its relation to antibody affinity.? Allergy 2001: 56: Suppl. 67: 27-29
http://immuneweb.xxmc.edu.cn/progress/1191.pdf
5 Caruso B, Bonadonna P, Severino M.G., Manfredi M, Dama A, Schiappoli M, Rizzzotti P, Senna G, Passalacqua G.?Evaluation of the IgE cross-reactions among vespid venoms. A possible approach for the choice of immunotherapy.?
Allergy 2007: 62: 561-564
6 Hamilton R.G., Wisenauer J.A., Golden D, Valentine M.D., Adkinson F. ?Selection of Hymenoptera venoms for immunotherapy on the basis of patient?s IgE antibody cross-reactivity.? Journal of Allergy and Clinical Immunology 1993: 92 (5): 651-
659
7 Reisman, R.E., Wypych J.I., Lazell M.I. ?Further Studies of Patients with Both Honeybee- and Yellow-Jacket-Venom-Specific IgE.? International Archives of Allergy and Immunology: 1987: 82: 190-194
8 Jappe U, Raulf-Heimsoth M, Hoffman M, Burow G, Hubsch-Muller C, Enk A. ?In Vitro hymenoptera venom allergy diagnosis: improved by screening for cross-reactive carbohydrate determinants and reciprocal inhibition.? Allergy 2006: 61: 1220
-1229.
For further information contact the laboratory (09) 307 4949 ext 22000 or:
Associate Professor Rohan Ameratunga , Immunopathologist: Locator 93-5724
Or the LabPLUS Immunology Team