RAGWEED POLLEN ALLERGY
Key Allergens
The ragweed plant is also sometimes known as Ambrosia. The World Health Organization recognises 15 allergens associated with allergy across 3 Ambrosia species. These are all allergens associated with airways.
Ragweed pollen occurs in the UK between August and September. This varies in different countries.
Amb a 1 is thought to be the most important ragweed allergen (in older texts it may be referred to as “antigen E”, with 95% of ragweed allergic patients being sensitised to this protein.
Amb a 6 is a
Lipid Transfer Protein (LTP), these are referred to as panallergens as they are allergens which can cause allergic reactions across many plants and foods.
Amb a 8 and Amb t 8 are both
profilin allergens. These are also panallergens which can cause serious allergic reactions, but more frequently seen in food allergies.
Amb a 9 and Amb a 10 are both
polcalcin proteins. These are another group of panallergens and are associated with calcium binding in the plant.
Amb a 12 is an
enolase protein.
Ragweed pollens also contain
plant defensin proteins which are peptides which protect the plant against fungal attack.
Other allergens found in ragweed are incredibly similar in structure which makes sufferers of ragweed pollen allergy excellent candidates for immunotherapy, which helps to reduce the allergic symptoms of ragweed induced rhinitis.
Associated Syndromes
You may have
Pollen Food Allergy Syndrome if you suffer from ragweed pollen allergy with
oral allergy symptoms to 3 or more of the foods mentioned in cross reactivity section.
Lipid Transfer Proteins (LTP) are found in many types of plants. You may be allergic to all or some of the foods mentioned in the cross reactivity section, this is known as
LTP Syndrome.
Latex Food Syndrome is also sometimes known as Latex Fruit Syndrome. When a person becomes sensitised to the allergens in latex they may also become sensitised to certain foods which contain similarly shaped proteins. Ragweed contains an enolase protein, which is also found in latex plants.
An allergy to birch pollen is strongly associated with seasonal allergic rhinitis (hayfever) as well as asthma, rhinoconjunctivitis and atopic dermatitis.
Cross Reactivity
Profilin allergens can be considered both pollen allergens and food allergens. Other plant pollens containing profilin are alder, birch, mugwort, bermuda grass, sunflower, olive, rice, timothy grass, poplar, mesquite and maize. Foods containing profilin proteins are kiwi, pineapple and celery.
Other plant pollens which contain polcalcin proteins are alder, mugwort, birch, timothy grass, lilac and olive. There is also a polcalcin protein in turnips which is associated with this allergy presenting itself as a food allergy.
Other plants containing enolase proteins which can affect your airways include bermuda grass, several types of fungus and moulds, yeast and penicillin. Enolase is also a recognised contact allergen in rubber trees, so is strongly related to latex.
Lipid Transfer Proteins most commonly affect ingested foods, but have been found to be airway allergens in wormwood, plane trees, hemp, olive and pellitory.
Those with a sensitivity to chitinase may have linked allergies to foods which contain high levels of chitinase, like avocado, banana, chestnuts, corn (maize), kiwi, papaya, pomegranate and tomatoes.
Other plant pollen containing defensins include soya, wormwood, sagebrush and mugwort. Defensin proteins are also found as food allergens in peanut, celery and chestnuts.
Resources
Websites
Allergy UK - Allergic rhinitis
Allergy UK - Managing your asthma and your allergic rhinitis throughout the seasons
ACAAI - Ragweed Allergy
Healthline - Ragweed Symptoms
BBC - Science/Environment
Asthma and Allergies - Ragweed Allergy
Allergic Living - All abut Ragweed
Allergen Encyclopedia - Ragweed
Dermnet NZ - Ragweed
Articles and Journals
Ambrosia (Ragweed) Pollen Significantly Contributed to the Biological Pollution in the late Spring and early Summer of 2023 in an Urban Community with high Asthma Rates in Jacksonville, Florida, 2024
Physicochemical and immunological characterization of Amb a 12, a novel ragweed (Ambrosia artemisiifolia) pollen allergen, 2023
Ragweed pollen concentration predicts seasonal rhino-conjunctivitis and asthma severity in patients allergic to ragweed, 2022
Spectrum and frequency of food allergy in Kyiv`s adult citizens with allergic rhinitis: a cross-sectional study, 2022
Ragweed sublingual immunotherapy (SLIT) tablets in allergic rhinoconjunctivitis: a systematic review and meta-analysis, 2022
Complex IgE sensitization patterns in ragweed allergic patients: Implications for diagnosis and specific immunotherapy, 2022
Randomized controlled trial of ragweed sublingual immunotherapy tablet in the subpopulation of Canadian children and adolescents with allergic rhinoconjunctivitis, 2021
Biological weed control to relieve millions from Ambrosia allergies in Europe, 2020
Cross‐reactivity in allergy: A double‐edged sword, 2019
Ragweed Pollen Allergy: Burden, Characteristics, and Management of an Imported Allergen Source in Europe, 2018
Modifiable Risk Factors for Common Ragweed (Ambrosia artemisiifolia) Allergy and Disease in Children: A Case-Control Study, 2018
Climate Change and Future Pollen Allergy in Europe, 2017
Your Grandchildren’s Pollen? Modelling the Future of Ragweed Sensitization in Europe, 2017
In children allergic to ragweed pollen, nasal inflammation is not influenced by monosensitization or polysensitization, 2016
Ragweed-induced allergic rhinoconjunctivitis: current and emerging treatment options, 2015
Ambrosia artemisiifolia (ragweed) in Germany – current presence, allergological relevance and containment procedures, 2015
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