Pla l 1
Summary
Pla l 1 is a major allergen of and marker of genuine sensitization to English plantain (Plantago lanceolata) pollen. Pla l 1 is a member of the Ole e 1-like pollen protein family but displays limited, clinically non relevant, cross-reactivity with other members of this family, most notably with Ole e 1 from olive pollen and Che a 1 from goosefoot pollen.
Epidemiology
Worldwide distribution
Plantago lanceolata is a frequent and increasing cause of weed pollinosis under temperate climate worldwide [1, 2].
Pla l 1 sensitization was initially observed in 86% of P. lanceolata-allergic patients [1]. Subsequent studies reported variable levels, from 92% [3] to 33% - 34% [4, 5] in patients with evocative symptoms and P. lanceolata whole allergen extract sensitization, depending on the methodology of subject inclusion, the geographical area, the relative frequency of pollen multisensitization and the contribution of other plantain allergens [2-5].
This variation is also seen in epidemiological studies addressing subjects referred with a suspicion of allergy, which report locally relevant values of Pla l 1 sensitization, ranging from 0.3 to 7% in Germany [6] and up to 9.6% of pollen-sensitized subjects in the Czech Republic [7].
Clinical Relevance
Detailed information regarding P. lanceolata pollinosis, which manifests itself mainly as allergic rhinitis, rhinoconjunctivitis and asthma, is available in the whole allergen section.
Disease severity and prediction
In patients with a case history evocative of P. lanceolata pollinosis and sensitization to P. lanceolata whole allergen extract, the demonstration of Pla l 1 IgE confirms genuine sensitization to this pollen, thus assisting with correct classification of multisensitized patients [5, 10, 12].
Cross-reactive molecules
Pla l 1 exhibits limited and clinically irrelevant cross-reactivity with the major olive pollen allergen Ole e 1 and with Ole e 1-like allergens such as Phl p 11 from Phleum pratense, Che a 1 from Chenopodium album and Sal k 5 from Salsola kali [10, 13].
Diagnostics
Marker allergen for sensitization to P. lanceolata pollen
Pla l 1 sensitization confirms genuine sensitization to P. lanceolata pollen and is found in 33-92% of patients with P. lanceolata pollinosis, depending on the study population, the geographic area and local pollen exposure [3, 5, 10, 12]. In areas of concomitant sensitization to grass and other weed pollen and overlapping pollination seasons, Pla l 1 assists with the identification of the primary sensitizer [10].
Cross-Reactivity
Pla l 1 does not cross-react with Ole e 1 and Ole e 1-like allergens from other pollens (olive, grass, weeds) [10]. Importantly, even in patients exhibiting IgE to Ole e 1 and other Ole e 1-like allergens, IgE inhibition experiments confirmed true co-sensitization to Pla l 1 and the absence of cross-reactivity [15]. Therefore, Ole e 1 should not be used as a surrogate marker for sensitization to Pla l 1 [10].
Exposure
The main route of exposure is through inhalation of P. lanceolata pollen [10].
References
- Calabozo, B., D. Barber, and F. Polo, Purification and characterization of the main allergen of Plantago lanceolata pollen, Pla l 1. Clin Exp Allergy, 2001. 31(2): p. 322-30.
- Forkel, S., et al., Allergic Rhinitis to Weed Pollen in Germany: Dominance by Plantain, Rising Prevalence, and Polysensitization Rates over 20 Years. Int Arch Allergy Immunol, 2020. 181(2): p. 128-135.
- Gadermaier, G., et al., Plantago lanceolata: an important trigger of summer pollinosis with limited IgE cross-reactivity. J Allergy Clin Immunol, 2014. 134(2): p. 472-5.
- San Nicolo, M., et al., Relevance of Major Allergens in Weed Pollen Allergy. Int Arch Allergy Immunol, 2021. 182(7): p. 637-641.
- Stemeseder, T., et al., Do Plantago lanceolata Skin Prick Test-Positive Patients Display IgE to Genuine Plantain Pollen Allergens? Investigation of Pollen Allergic Patients from the North-East of France. Int Arch Allergy Immunol, 2018. 177(2): p. 97-106.
- Hoflich, C., et al., Management of patients with seasonal allergic rhinitis: Diagnostic consideration of sensitization to non-frequent pollen allergens. Clin Transl Allergy, 2021. 11(8): p. e12058.
- Panzner, P., et al., A comprehensive analysis of middle-European molecular sensitization profiles to pollen allergens. Int Arch Allergy Immunol, 2014. 164(1): p. 74-82.
- Castro, A.J., et al., Pla 1 1 and Ole e 1 pollen allergens share common epitopes and similar ultrastructural localization. J Investig Allergol Clin Immunol, 2007. 17 Suppl 1: p. 41-7.
- Gonzalez Parrado, Z., et al., Molecular aerobiology - Plantago allergen Pla l 1 in the atmosphere. Ann Agric Environ Med, 2014. 21(2): p. 282-9.
- Matricardi, P.M., et al., EAACI Molecular Allergology User's Guide. Pediatr Allergy Immunol, 2016. 27 Suppl 23: p. 1-250.
- Gheerbrant, H., et al., Associations between specific IgE sensitization to 26 respiratory allergen molecules and HLA class II alleles in the EGEA cohort. Allergy, 2021. 76(8): p. 2575-2586.
- Til-Perez, G., et al., Sensitization profile in patients with respiratory allergic diseases: differences between conventional and molecular diagnosis (a cross-sectional study). Clin Mol Allergy, 2019. 17: p. 8.
- Barderas, R., et al., Identification and characterization of Che a 1 allergen from Chenopodium album pollen. Int Arch Allergy Immunol, 2002. 127(1): p. 47-54.
- Castro, L., et al., Sal k 5, a member of the widespread Ole e 1-like protein family, is a new allergen of Russian thistle (Salsola kali) pollen. Int Arch Allergy Immunol, 2014. 163(2): p. 142-53.
- Stemeseder, T., et al., Crystal structure of Pla l 1 reveals both structural similarity and allergenic divergence within the Ole e 1-like protein family. J Allergy Clin Immunol, 2017. 140(1): p. 277-280.
- Calabozo, B., et al., Cloning and expression of biologically active Plantago lanceolata pollen allergen Pla l 1 in the yeast Pichia pastoris. Biochem J, 2003. 372(Pt 3): p. 889-96.
- Fernandez-Gonzalez, M., et al., Secondary Outcomes of the Ole e 1 Proteins Involved in Pollen Tube Development: Impact on Allergies. Front Plant Sci, 2020. 11: p. 974.
- IUIS/WHO. IUIS/WHO Plantago lanceolata. 2022 2022 January 13]; Available from: http://allergen.org/search.php?allergenname=&allergensource=plantain&TaxSource=&TaxOrder=&foodallerg=all&bioname=.