w4 False Ragweed

w4 False Ragweed Scientific Information

Type:

Whole Allergen

Display Name:

False Ragweed

Allergen code:

Family:

Asteraceae (Compositae)

Latin Name:

Franseria acanthicarpa (Synonym: Ambrosia acanthicarpa)

Other Names:

False Ragweed, Bur ragweed, Annual Burweed

Molecular Aspects

No allergens from this plant have yet been characterized.

Cross-reactivity

An extensive cross-reactivity among the different individual species of the genus could be expected, as well as to a certain degree among members of the family Asteraceae. (3, 4) This was confirmed in a study using a serum pool from patients sensitive to Short Ragweed, whereby the cross-reactivity of IgE antibodies to six Ragweeds was studied through the radioallergosorbent test. Extracts were analyzed for their inhibitory activities, with solid-phase allergens prepared from all of the Ragweed pollens. Also, samples of serum were absorbed with the various solid-phase allergens and the reactivity of the remaining IgE antibodies was determined. Two patterns of reactivity were observed. Short, Giant, Western, and False Ragweeds displayed comparable reactivity in both inhibition and absorption experiments. Slender and Southern Ragweed were considerably less active, indicating that they lacked allergenic groupings possessed by the other species. These same patterns of cross-reactivity were found using Ragweed pollens from four commercial sources. (5)

A second study documented close cross-reactivity between False Ragweed and Short Ragweed. A water-insoluble material, extracted from Short Ragweed and False Ragweed pollen, contained at least five proteins. Two (RFA2 and RFB2) were isolated and shown to possess antigenicity as well as allergenicity. Immunodiffusion tests of RFB2, isolated from False Ragweed and Short Ragweed, showed immunological identity.(6)

Compiled By

Last reviewed:April 2022

References

Mohapatra SS, Lockey RF, Polo F. Weed pollen allergens. Clinical allergy and immunology. 2008;21:127-39.
Guin JD, Skidmore G. Compositae dermatitis in childhood. Archives of dermatology. 1987;123(4):500-2.
L. Y. Botanical relations and immunological cross-reactions in pollen allergy. 2nd ed. Pharmacia Diagnostics AB. Uppsala. Sweden. Pharmacia Diagnostics AB Uppsala Sweden. 1982.
Weber RW. Cross-reactivity of pollen allergens: impact on allergen immunotherapy. Ann Allergy Asthma Immunol. 2007;99(3):203-11; quiz 12-3, 31.
Leiferman KM, Gleich GJ, Jones RT. The cross-reactivity of IgE antibodies with pollen allergens. II. Analyses of various species of ragweed and other fall weed pollens. The Journal of allergy and clinical immunology. 1976;58(1 pt. 2):140-8.
Su SN, Harris J, Lau GX, Han SH. Aqueous-organic solvent extraction of water-insoluble protein from ragweed pollen. Zhonghua Minguo wei sheng wu ji mian yi xue za zhi = Chinese journal of microbiology and immunology. 1987;20(2):104-12.