Cashew Tree Pollen: An Unknown Source of IgE-Reactive Molecules

Abstract

Pollinosis is sub-diagnosed and rarely studied in tropical countries. Cashew tree pollen has been reported as an allergen source although the knowledge of its immunoglobulin E (IgE)-reactive molecules is lacking. Therefore, this work aimed to identify IgE-reactive molecules and provide a proteomic profile of this pollen. From the 830 proteins identified by shotgun analysis, 163 were annotated to gene ontology, and a list of 39 proteins filtered for high confidence was submitted to the Allfam database where nine were assigned to allergenic families. Thus, 12 patients from the northeast of Brazil with persistent allergic rhinitis and aggravation of symptoms during cashew flowering season were selected. Using a 2D-based approach, we identified 20 IgE-reactive proteins, four already recognized as allergens, including a homolog of the birch isoflavone-reductase (Bet v 6). IgE-reactivity against the extract in native form was confirmed for five patients in ELISA, with three being positive for Bet v 6. Herein, we present a group of patients with rhinitis exposed to cashew tree pollen with the first description of IgE-binding proteins and a proteomic profile of the whole pollen. Cashew tree pollen is considered an important trigger of rhinitis symptoms in clinical practice in the northeast of Brazil, and the elucidation of its allergenic molecules can improve the diagnostics and treatment for allergic patients.

Precision environmental health monitoring by longitudinal exposome and multi-omics profiling

“…Members of these genera were found to be involved in complex physiological mechanisms and may show adverse health effects. For example, species of Isaria were found to induce cell death ( Chhetri et al 2020 ); species of Sporothrix triggered skin and lung inflammatory reactions ( de Lima Barros et al 2011 ); and the pollen of Tarenaya members generate immunoglobulin E–mediated allergic reactions ( Danella Figo et al 2019 ). In addition, certain types of agrochemicals, PPCPs, and flame retardants that we detected are high-degree chemical stressors known to cause epigenetic alterations, endocrine disruption, impaired nervous system function, oxidative stress, and inflammation ( Peters et al 2021 ).…”

Identification of fructose‐bisphosphate aldolase as new pollen allergens

“…3 Recently, fructose-bisphosphate aldolase, an essential enzyme in glycolysis and gluconeogenesis, was presented as IgE-reactive proteins in several pollen species. [4][5][6] These results gave a good clue for the investigation of the role of fructose-bisphosphate aldolase in pollen allergy. However, the lack of further verifications at the mRNA and protein level, such as no purified natural or recombinant allergens as well as their allergenicity data, no cDNA sequence and no full-length amino acid sequence, making it only a potential and undefined pollen allergen.…”

Precision environmental health monitoring by longitudinal exposome and multi-omics profiling

“…Members of these genera were found to be involved in complex physiological mechanisms and may exhibit adverse health effects. For example, species of Isaria were found to induce cell death 53 , species of Sporothrix triggered skin and lung inflammatory reactions 54 , and the pollen of Tarenaya members are allergens and generate immunoglobulin-E mediated allergic reactions 55 . Also, certain types of agrochemicals, PPCPs, and flame retardants that we detected are high-degree chemical stressors known to cause epigenetic alterations, endocrine disruption, impaired nervous system function, oxidative stress, and inflammation 46 .…”