Russian olive
Allergen
Allergens
In a study of 134 patients in Madrid, major IgE-binding bands in Russian olive extract, with molecular weights of 37, 43, 63.7 and 77.4 kDa, were recognised in 40%, 65%, 50% and 45% of patients, respectively. No allergens have been characterised to date.
Clinical Relevance
IgE-mediated reactions
Although only sparse reports document sensitisation to Russian olive tree, anecdotal evidence suggests that asthma and hayfever are possible following exposure to pollen from this tree. In a study of 134 patients in Madrid with rhinoconjunctivitis and/or asthma, 73 (30.5%) were found to have a positive skin test to Russian olive tree, and all were positive to Olive (Olea europaea) as well. A nasal challenge with Russian olive tree was positive in 3 of 6 patients with a positive skin test to both pollens, and negative in 5 patients with a positive skin test to Olive tree only. It has been suggested that a positive skin test to Olive pollen in regions where Olive trees are not present may be due to a sensitisation to Russian olive or other cross-reactive pollens.
Cross-Reactivity
In 103 Michigan residents with symptoms suggestive of allergic rhinitis or asthma, who were skin-tested with Olive tree (Olea europaea) pollen extract, 19 had positive reactions. As the Olive tree is not present in this area, an evaluation was made as to whether these findings were the result of cross-reactivity among the tree pollen allergens from Olive, Ash (Fraxinus americana), Privet (Ligustrum vulgare), and Russian olive. On ELISA testing, 11 of the 19 skin-test-positive patients were Olive positive, 8 were positive to Ash, 7 to Privet and 10 to Russian olive, and inhibition studies demonstrated that all 3 of these tree pollens were capable of inhibiting the binding of IgE in a dose-response fashion. Several proteins common to Olive, Ash, and Privet were demonstrated. Of the 12 Olive skin-test-positive patients contacted, 75% confirmed exposure to 1 or more of the studied trees in their yards. In a study conducted in Madrid, Spain, all patients with a positive skin test to Russian olive were also positive to Olive; but not all Olive-positive patients were positive to Russian olive. In inhibition studies, the Russian olive extract was not able to inhibit Olive, whereas an Olive extract inhibited Russian olive by up to 41%, establishing minimal to moderate cross-reactivity between Olive tree and Russian olive tree, but not excluding cosensitisation. The presence of Ole e 1- and Ole e 4-like allergens in Russian olive tree extract was confirmed.
References
- Weber RW. Russian olive. Ann Allergy Asthma Immunol 2004;92(1):A6
- Farrar JL. Trees of the Northern United States and Canada. Ames, IA: Iowa State University Press; 1995:407
- Lewis WH, Vinay P, Zenger VE. Airborne and Allergenic Pollen of North America. Baltimore, MD: Johns Hopkins University Press; 1983:39-41,189
- Sastre J, Lluch-Bernal M, Bustillo AM, Carnes J, Maranon F, Casanovas M, Fernandez-Caldas E. Allergenicity and cross-reactivity of Russian olive pollen (Eleagnus angustifolia). Allergy 2004;59(11):1181-6
- Wikipedia contributors, ”Elaeagnus angustifolia”, Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Elaeagnus_angustifolia&oldid=204287448 (accessed July 7, 2008)
- Kernerman SM, McCullough J, Green J, Ownby DR. Evidence of cross-reactivity between olive, ash, privet, and Russian Olive tree pollen allergens. Ann Allergy 1992;69(6):493-6
- Carnes J, Fernandez-Caldas E. Ole e 4 and Ole e 5, important allergens of Olea europaea. Allergy 2002;57 Suppl 71:24-8