Olive Pollen Research Articles

Effects of classical and organomineral fertilizer applications on pollen quality and quantity in gemlik olive cultivar

Olive is one of the important plants worldwide in terms of economic and cultural conditions. It is used in fresh consumption, olive oil, cosmetic and pharmaceutic fields and unique numinous plants. Olive can maintain its life for many years even in barren conditions but for an economic cultivation, fertile and preferred cultivars should be used in orchards and optimum maintenance conditions should be provided. At the same time the climate change is also convert the usual behavior of the plants. This study aims to determine the effects of classic and organomineral fertilizers on pollen quality and quantity parameters. In this study, classical fertilizers like Urea+MgSO4 and KNO3+H3BO3+ZnSO4 with Raykat Start, Raykat Growth and Fitomare organomineral fertilizers were sprayed foliarly before flowering on Gemlik olive cultivar and pollen studies were conducted on the flowers formed at full flowering. Within the study, effects of the treatments were evaluated on pollen viability and germination levels, the amount of pollen produced in one flower and the normally developed pollen ratio. As a result of this study, fertilization treatments positively affected pollen quality and quantity with regard to control treatment. In this context, the pollen viability level differed between 74.15% and 89.92%, the pollen germination level between 45.48% and 70.35% and pollen per flower was between 307.238 and 446.761. The lowest data were obtained from control treatments, while the highest were from Raykat group fertilizers. Especially, the 54% increase in pollen germination level with Raykat growth fertilization was one of the most important results of this study. In conclusion, it was determined that the foliar spray of organomineral fertilizers enhanced the pollen properties. Raykat Start, Raykat Growth and Fitomare organomineral fertilizers used in this study significantly increased pollen quality and quantity.

Aerobiology of Olive Pollen (Olea europaea L.) in the Atmosphere of the Iberian Peninsula

Olea europaea L. pollen is one of the main causes of pollinosis and respiratory diseases in the Iberian Peninsula (IP). The aim of this study was to provide a pollen calendar in different regions of the IP, which could help allergists and allergic patients in the management of Olea europaea allergic diseases, and to update/complement what has already been reported on olive trees’ aeropalynology in this region. Airborne Olea pollen dynamics were analyzed over a period of 8 years in a total of 21 localities, 7 in Portugal and 14 in Spain. Airborne pollen monitoring was carried out using the Hirst-type spore trap method and following the recommendations of the Quality Control Working Group of the European Aerobiology Society. The daily pollen count, the annual pollen profile, the Annual Pollen Integral (APIn), the Seasonal Pollen Integral (SPIn) and the Pollen Peak, all expressed in number of pollen grains per cubic metre of air, together with the main pollen season and its characteristics, the Start Day, the End Day and the length of the pollen season, were calculated for each sampling station. Differences in mean Olea pollen concentration between odd and even years were also analyzed. On average, the main pollen season (MPS) started in April/May and ended in June, with Pollen Peaks recorded in May, except in Burgos, where it was recorded in June. The longest MPS occurred in Lisbon, Oviedo and Valencia (53 days) and the shortest in Vitoria (25 days). A high daily pollen concentration (i.e., >200 grains/m3) was recorded between 1 and 38 days along the year in all sampling stations of the southwest quadrant of the IP and in Jaén. A biannual pattern, characterized by alternating years of high and low pollen production, was found in the southwest of the IP. In conclusion, the study provided a deeper understanding of the pollination behaviour of olive trees in the IP and allowed the establishment of a representative Olea pollen calendar for this region. In addition, our results suggest the usefulness of investigating more detailed relationships between annual Olea pollen, allergen sensitization and symptoms, both for allergists involved in the study and management of allergic respiratory diseases caused by this species and for the self-management of disease in allergic subjects.

Pollen-Food Allergy Syndrome: From Food Avoidance to Deciphering the Potential Cross-Reactivity between Pru p 3 and Ole e 7.

Cross-reactivity between nonspecific lipid transfer proteins could cause anaphylaxis, further influencing food avoidance and nutrient deficiencies. The one affecting olive pollen (Ole e 7) and peach (Pru p 3) may underlie a variety of pollen-food syndromes, though a deep molecular analysis is necessary. Three Ole e 7-monosensitised patients (MON_OLE), three Pru p 3-monosensitised patients (MON_PRU) and three bisensitised patients (BI) were selected. For epitope mapping, both digested proteins were incubated with patient sera, and the captured IgE-bound peptides were characterised by LC-MS. The analysis revealed two Ole e 7 epitopes and the three Pru p 3 epitopes previously described. Interestingly, the "KSALALVGNKV" Ole e 7 peptide was recognised by MON_OLE, BI and MON_PRU patients. Conversely, all patients recognised the "ISASTNCATVK" Pru p 3 peptide. Although complete sequence alignment between both proteins revealed 32.6% identity, local alignment considering seven residue fragments showed 50 and 57% identity when comparing "ISASTNCATVK" with Ole e 7 and "KSALALVGNKV" with Pru p 3. This study mapped sIgE-Ole e 7-binding epitopes, paving the way for more precise diagnostic tools. Assuming non-significant sequence similarity, structural homology and shared key residues may underlie the potential cross-reactivity between Ole e 7 and Pru p 3 nsLTPs.

Comparison of Olea pollen sampling between gravimetric and volumetric traps (NW of Morocco)

Olea pollen is considered one of the most critical causes of respiratory allergic disease in the Mediterranean region, contributing to different symptoms in allergic sufferers. Due to the high increase in the prevalence of olive pollen caused by the expansion of cultivated areas especially in the Mediterranean region, the aim of this study was to examine the Olea pollen sampling efficiency between gravimetric and volumetric pollen traps over the period 2018–2022. Our data demonstrated that Olea pollen season start-date was generally recorded earlier with volumetric trap than shown with gravimetric method. Moreover, the peak dates occurred mainly in May for the years studied. Across the entire period, the greatest pollen concentrations were reached in the week 11th and >60 % of the total Olea pollen were already reached after the ninth week of sampling in 2020. In general, the evolution of pollen sampling for both methods demonstrates similar temporal development. Variations in the seasonal pollen integral could be attributed to the elevation above ground level at which the traps were placed, exposure to regional winds, the influence of long-range transported pollen and the mode of pollen transport. The findings indicate that the gravimetric method was equally practical as the volumetric method in estimating airborne pollen.

Retrospective, Real Life Study on the Effectiveness and Safety of a Depigmented-Polymerized Subcutaneous Vaccine Containing a Mixture of Grasses and Olea europaea

Introduction: Allergen immunotherapy is the only modifying treatment of the natural course of respiratory allergic diseases; however, the lack of evidence leads to little inconclusive results. Real life studies are on the rise and are becoming a valuable tool to confirm and complement findings from clinical trials. The objective of this study was to evaluate the effectiveness and safety of a depigmented-polymerized undiluted subcutaneous extract of grass and olive pollen, under routine clinical practice conditions. Methods: This was an observational, retrospective, longitudinal, single-center study on the use of a 2-pollen (grass mix and Olea europaea) undiluted subcutaneous extract over at least 3 consecutive years. Data were collected from 76 patients (n = 44 female; median age: 12.5 years old) diagnosed with allergic rhinoconjunctivitis with/without allergic asthma due to sensitization to both grasses and O. europaea. Primary and secondary effectiveness endpoints were symptom severity, concomitant medication, and immunological profile before and after completing the immunotherapy. A 2-year follow-up of patients’ symptoms and medication history after completing the subcutaneous immunotherapy (SCIT) was performed. Results: There was a significant improvement of symptoms and medication consumption after 3 years of SCIT treatment, and a significant decrease in specific IgE levels for grasses and O. europaea was observed after finishing the treatment. Conclusion: Three years treatment of allergic patients using an undiluted mixture of two allergen extracts was shown to be safe and effective for rhinitis and asthma, with efficacy maintained for at least 2 years after finishing SCIT. These results reinforce the importance of real life clinical data in addition to those from clinical trials, helping to individualize allergic treatments.

Pollen- and Weather-Based Machine Learning Models for Estimating Regional Olive Production

The olive tree is one of the most common type of cultivation in the Mediterranean area, having high economic and social importance. The Alentejo region, Portugal, is an area with a high presence of olive groves, which in 2022 accounted for 201,474 hectares. The aim of this study was to assess the relationship between olive pollen, weather data, and olive tree production, between the years 2002 and 2022. Pollen data were obtained from an urban station located in Évora, in the Alentejo region, and were used to calculate several metrics, such as the Pollen Season Duration (PSD), Seasonal Pollen Index (SPIn), peak value, and weekly pollen accumulation values. Monthly minimum, maximum, and mean temperature and precipitation sums were obtained from the E-OBS observational dataset. Considering the relationship between pollen/weather and olive production, mutual information and correlation analyses were conducted. Subsequently, several machine learning algorithms were trained using pollen and weather datasets, and we obtained suitable forecast models for olive tree production after cross-validation. The results showed high variability in pollen concentrations in Évora over the years. Complex associations were found, with certain weeks of pollen accumulation showing significant mutual information with olive production, particularly during June. The analyzed linear correlation coefficients remained generally low, underscoring the challenge of predicting olive production based on linear relationships. Among the machine learning algorithms employed to predict olive production, Decision Trees, Extreme Gradient Boosting, and Gradient Boosting Regressor were the most robust performers (r2 > 0.70), while linear models displayed a subpar performance (r2 < 0.5), emphasizing the complexity of this approach. These models highlight the roles of maximum and minimum temperatures during March and May and pollen accumulation during the second half of June. The developed models may be used as decision-support tools by growers and stakeholders to further enhance the sustainability of the thriving olive sector in southern Portugal.

Molecular sensitization profile to grass and olive pollens in Portugal.

Background. Grass and olive pollens have overlapping pollination periods and are common allergens in the Iberian Peninsula. The objective is to determine the sensitization pattern to major Phleum pratense and Olea europaea pollens in the Portuguese population with pollen allergic rhinitis (AR) using molecular allergen diagnosis (MAD). Methods. Seasonal AR patients (≥ 12 years), with positive skin prick tests (SPT) to Phleum and Olea were recruited from 16 centers. Using ALEX2, specific IgE to Phl p1, Phl p2, Phl p5, Phl p6, Phl p7, Phl p 12, Ole e1, Ole e7 and Ole e9 were determined. Immunoblotting of Olea allergic patients was performed. Results. Included 175 patients (55.4% female; mean age 31.6 ± 13.3 years; 85.7% adults; 40% asthmatic, Coast 28%/Inland 72% and North 29.1%/Centre 20.6%/South 50.3%). Considering Phleum MAD, 85.7% were sensitized to Phl p1, 45.7% to Phl p2, 50.3% to Phl p5, 45.7%, to Phl p6, 10.9% to Phl p7 and 22.9% to Phl p12. Sensitization to Ole e1 was found in 56.6%, to Ole e7 in 1.7% and Ole e9 in 3.4% patients. Sensitization to Phl p7 was more frequent in asthmatics (17.4% vs 6.6%; p = 0.044). Sensitization to Phl p5, Phl p6, Phl p12 and Ole e1 was more frequent in inland. Regarding sensitization patterns: 53.1% patients were sensitized to both species genuine´ sIgE, 38.3% to Phleum and 3.4% only to Olea species' sIgE. Immunoblotting of Olea allergic patients showed a high intensity band that may correspond to Ole e12. Conclusions. MAD showed "genuine" Grass and Olea sensitization in approximately 50% of our patients.

Pollination and pollen plant diversity by Apis cerana cerana during olive flowering based on DNA metabarcoding

AbstractTo understand the role of Apis cerana cerana in olive tree (Olea europaea L.) pollination, pollinators and pollen carried by bees were collected from 11 experimental plots during the flowering period. The abundance and diversity of pollen plant species were investigated using DNA metabarcoding. A total of 583 pollinators were collected and A. cerana cerana accounts for 46.83%. Further analysis revealed a total of 56 families, 136 genera and 195 plant species in bee pollens. O. europaea is the dominant species accounting for 42.02 ± 34.89% and then followed by Sedum japonicum (8.70 ± 16.42%). Diversity index showed that the abundance and diversity of pollen plant species were the highest in Wanzhou (WZ) and lowest in Hechuan (HC). This suggests that Wanzhou sample plot has a greater abundance of plant species to supplement the bee diet. Excessive presence of miscellaneous flowering plants in olive plantations can distract bees from collecting olive tree pollens. Therefore, their abundances can be reduced appropriately while ensuring food diversity for the bees. Based on the abundance of plants in pollens, we recommend that appropriately planting of S. japonicum, Youngia japonica and Vicia villosa in olive plantations with fewer flowering plants could be an effective supplement of bee food. Our results not only contribute to future studies on olive tree pollination but also provide new ideas for enriching flowering plants in or around olive plantations.

Methylation-driven mechanisms of allergic rhinitis during pollen and non-pollen seasons using integrated bioinformatics analysis.

Allergic rhinitis (AR) is a widespread allergic airway disease that results from a complex interplay between genetic and environmental factors and affects approximately 10%-40% of the global population. Pollen is a common allergen, and exposure to pollen can cause epigenetic changes. However, the mechanism underlying pollen-induced DNA methylation changes and their potential effects on the allergic march are still unclear. The purpose of this study was to explore the methylation-driven mechanisms of AR during the pollen and non-pollen seasons using bioinformatics analysis and to investigate their relationship with asthma. We downloaded DNA methylation and gene expression data from the GEO database (GSE50387: GSE50222, GSE50101) and identified differentially methylated positions (DMPs) and differentially expressed genes (DEGs) during the pollen and non-pollen seasons using the CHAMP and limma packages. Through correlation analysis, we identified methylation-driven genes and performed pathway enrichment analysis to annotate their functions. We incorporated external data on AR combined with asthma (GSE101720) for analysis to identify key CpGs that promote the transformation of AR to asthma. We also utilized external data on olive pollen allergy (GSE54522) for analysis to validate the methylation-driven genes. Weighted correlation network analysis (WGCNA) was employed to identify gene modules significantly correlated with pollen allergy. We extracted genes related to the key methylation-driven gene ZNF667-AS1 from the significant module and performed pathway intelligent clustering using KOBAS-i. We also utilized gene set enrichment analysis to explore the potential function of ZNF667-AS1. We identified 20 and 24 CpG-Gene pairings during the pollen and non-pollen seasons. After incorporating external data from GSE101720, we found that ZNF667-AS1 is a key gene that may facilitate the transformation of AR into asthma during the pollen season. This finding was further validated in another external dataset, GSE54522, which is associated with pollen allergy. WGCNA identified 17 modules, among which the blue module showed significant correlation with allergies. ZNF667-AS1 was located in the blue module. We performed pathway analysis on the genes correlated with ZNF667-AS1 extracted from the blue module and identified a prominent cluster of pathways in the KOBAS-i results, including Toll-like receptor (TLR) family, MyD88, MAPK, and oxidative stress. Gene set enrichment analysis around cg05508084 (paired with ZNF667-AS1) also indicated its potential involvement in initiating and modulating allergic inflammation from the perspective of TLR and MAPK signaling. We identified methylation-driven genes and their related pathways during the pollen and non-pollen seasons in patients with AR and identified key CpGs that promote the transformation of AR into asthma due to pollen exposure. This study provides new insights into the underlying molecular mechanisms of the transformation of AR to asthma.

Identification and semi-quantification of protein allergens in complex mixtures using proteomic and AllerCatPro 2.0 bioinformatic analyses: a proof-of-concept investigation

The demand for botanicals and natural substances in consumer products has increased in recent years. These substances usually contain proteins and these, in turn, can pose a risk for immunoglobulin E (IgE)-mediated sensitization and allergy. However, no method has yet been accepted or validated for assessment of potential allergenic hazards in such materials. In the studies here, a dual proteomic-bioinformatic approach is proposed to evaluate holistically allergenic hazards in complex mixtures of plants, insects, or animal proteins. Twelve commercial preparations of source materials (plant products, dust mite extract, and preparations of animal dander) known to contain allergenic proteins were analyzed by label-free proteomic analyses to identify and semi-quantify proteins. These were then evaluated by bioinformatics using AllerCatPro 2.0 (https://allercatpro.bii.a-star.edu.sg/) to predict no, weak, or strong evidence for allergenicity and similarity to source-specific allergens. In total, 4,586 protein sequences were identified in the 12 source materials combined. Of these, 1,665 sequences were predicted with weak or strong evidence for allergenic potential. This first-tier approach provided top-level information about the occurrence and abundance of proteins and potential allergens. With regards to source-specific allergens, 129 allergens were identified. The sum of the relative abundance of these allergens ranged from 0.8% (lamb’s quarters) to 63% (olive pollen). It is proposed here that this dual proteomic-bioinformatic approach has the potential to provide detailed information on the presence and relative abundance of allergens, and can play an important role in identifying potential allergenic hazards in complex protein mixtures for the purposes of safety assessments.

Agreement of Peru‐Based Allergy Tests for Respiratory Allergens in Allergic Rhinitis Patients

Background. The Peruvian Immunoblot panel, together with traditional skin prick tests (SPT), are widely used in vitro allergy tests in Peru. In addition to this, Peruvian allergists are increasingly adopting multiplex tests such as the ALEX‐2 (Macro Array Diagnostics). Previous studies have revealed limited agreement between Immunoblot and SPT results. Therefore, our study aimed to evaluate the concordance between these three tests in patients with allergic rhinitis (AR) in a private center in Arequipa, Peru. Materials and Methods. We enrolled 35 patients, including children over 3 years and adults, with AR. Clinical and demographic data were collected, and patients underwent allergic sensitization testing using the Immunoblot Peruvian panel (32 allergens), ALEX‐2 (295 allergens), and SPT (12 allergens). Concordance was calculated using Cohen’s kappa coefficient and analyzed with IBM SPSS V26. Results. Among the patients, 34.3% exhibited moderate‐to‐severe persistent AR, and 14.3% had asthma. Additionally, 85.7% reported a family history of AR. Sensitization rates varied notably between the SPT and ALEX‐2, particularly for olive pollen (34.3% vs. 17.4%), Blomia tropicalis (11.4% vs. 17.1%), and grasses (11.4% vs. 28.5%). Remarkably, these allergens were not included in the Peruvian Immunoblot panel. Concordance analysis included seven allergens and showed significant concordance between ALEX‐2 and SPT for five allergens, between Immunoblot and SPT for two allergens, and between ALEX‐2 and Immunoblot for two allergens. Conclusion. This preliminary study shows us a better concordance between ALEX‐2 and SPT rather than between Immunoblot and SPT.

Allergic sensitization does not influence advancement or survival in oral cancer

A history of allergies has been said to be associated with a lower risk of head and neck cancer compared to the general population. However, it is not known whether having an allergic sensitization influences the prognosis and advancement of cancer disease. Thus, the aim of the study was to investigate the relationship between allergic sensitization and oral cancer advancement and patient survival. Allergen-specific IgE antibodies were investigated by ImmunoCAP™ Rapid in consecutive 80 patients with oral cancer. ImmunoCAP Rapid system tests a mix of representative inhalant allergens such as birch, timothy grass, mugwort, house dust mite, cat, dog, cockroach, olive (pollen), wall pellitory and mold. Eighty patients met the inclusion criteria for the study. Fifteen patients (19%) had positive ImmunoCAP test. There was no statistically significant difference in primary tumour size (T-stage) between groups (60% in allergy vs 68% in non-allergy had T1–T2 stage and 40% vs 32% T3–T4, respectively, p = 0.570). 27% of patients with allergy had nodal metastases compared with 37% of patients without allergy (p = 0.557). Both groups had comparable short-term survival. In conclusion, allergic sensitization does not seem to influence either the advancement or the short-term survival of patients with oral squamous cell carcinoma.

Back to basics: likelihood ratios for olive and grass pollen specific IgE in seasonal allergic rhinitis.

Specific IgE (sIgE) is merely a sensitization marker that cannot be used for allergy diagnosis if there are no associated clinical symptoms. As of 2023, there is still no evidence regarding the quantity of sIgE necessary to confirm or exclude clinical disease. Therefore, this study aimed to calculate cut-offs for sIgE, allowing us to effectively diagnose olive or grass pollen allergy and select allergenic immunotherapy (AIT) candidate patients in a region under high olive and grass allergenic pressure. An observational retrospective study consisting of the review of electronic medical records from 1,172 patients diagnosed with seasonal rhino-conjunctivitis and suspected allergy to olive or grass pollen. Symptoms correlated with sIgE to Poaceae and Oleaceae whole extracts and sIgE to genuine allergenic components were evaluated. Optimal cut-off values were calculated using receiver operating characteristic curves. Relevant clinical symptoms and AIT indications were taken into consideration when determining the clinical allergy diagnosis. sIgE to Lolium showed the best area under the curve (AUC) for both diagnosis (0.957) and an indication of AIT (0.872). The optimal cut-off values for grass diagnosis and AIT indication were 1.79 kUA/L and 8.83 kUA/L, respectively. A value of 5.62 kUA/L was associated with a positive likelihood ratio (LR) of 10.08 set for grass allergy. Olea sIgE showed the best AUC for the diagnosis (0.950). The optimal cut-off for diagnosis was 2.41 kUA/L. A value of 6.49 kUA/L was associated with a positive LR of 9.98 to confirm olive pollen allergy. In regard to immunotherapy, Ole e 1 sIgE showed the best AUC (0.860). The optimal cut-off was 14.05 kUA/L. Ole e 1 sIgE value of 4.8 kUA/L was associated with a 0.09 negative LR to exclude olive AIT indication. The sIgE cut-offs found in this population under high olive and grass allergenic pressure reduce the gap between sensitization and clinical allergy, providing a new tool for the diagnosis of seasonal allergic rhinitis/asthma and helping to discriminate patients who will benefit from AIT.

Co-exposure to highly allergenic airborne pollen and fungal spores in Europe

The study is aimed at determining the potential spatiotemporal risk of the co-occurrence of airborne pollen and fungal spores high concentrations in different bio-climatic zones in Europe. Birch, grass, mugwort, ragweed, olive pollen and Alternaria and Cladosporium fungal spores were investigated at 16 sites in Europe, in 2005–2019. In Central and northern Europe, pollen and fungal spore seasons mainly overlap in June and July, while in South Europe, the highest pollen concentrations occur frequently outside of the spore seasons. In the coldest climate, no allergy thresholds were exceeded simultaneously by two spore or pollen taxa, while in the warmest climate most of the days with at least two pollen taxa exceeding threshold values were observed. The annual air temperature amplitude seems to be the main bioclimatic factor influencing the accumulation of days in which Alternaria and Cladosporium spores simultaneously exceed allergy thresholds. The phenomenon of co-occurrence of airborne allergen concentrations gets increasingly common in Europe and is proposed to be present on other continents, especially in temperate climate.

Identifying Similar Allergens and Potentially Cross-Reacting Areas Using Structural Database of Allergenic Proteins (SDAP) Tools and D-Graph.

The Structural Database of Allergenic Proteins (SDAP) provides rapid search tools to identify similarities among allergens, their IgE epitopes, and to determine the potential allergenicity of any novel protein. Many labs have identified IgE-binding proteins and their antibody binding or T cell epitopes using dotspots or microarrays. This chapter describes how to determine the relationship of these proteins and peptides to known allergens using the tools implemented in SDAP. One can also search with these smaller peptide similarity search tool implemented in SDAP to find similar sequences with low property distance (PD) values in the over 1500 sequences of allergens. The sequences can be compared by mapping on the surface of the protein structures provided for nearly all the allergens in SDAP. Once the user has a unique list of similar sequences, they can be graphed in 2D according to interpeptide PD values calculated automatically by the D-graph program. This chapter provides a step-by-step description of how to do this, starting from a protein similar to the Ole e 1 (olive pollen) allergen family.

The distribution of sensitization to common aeroallergens in patients with rhinitis and asthma in Şanlıurfa, Türkiye.

Sensitization to common environmental aeroallergens plays a significant role in the pathogenesis and severity of asthma and allergic rhinitis. Knowledge on the sensitization pattern helps allergen avoidance, prediction of the severity of the disease, and use of specific immunotherapy for the most common allergens. The distribution of sensitization to aeroallergens differs in every region of Türkiye. In this study, it was aimed to investigate the allergen sensitization profiles of patients with asthma and rhinitis in Şanlıurfa, which is in Southeast Türkiye. Patients with rhinitis and asthma who presented to the outpatient clinic of adult immunology and allergy between April 2021- 2022 were retrospectively evaluated. Demographic information (age, sex), rhinitis and asthma duration, location of residence, allergic and non-allergic comorbidities, smoking history and skin prick test results were extracted from medical records. A total of 472 skin prick tests were performed on patients (35.4% males; 64.6% females), with a mean age of 33.8 years, and 120 (25.4%) were negative for skin reaction. The frequency of sensitivity to allergens was: grass (42.6%), cereal mixtures (41.5%), timothy grass (37.9%), cockroach (37.3%), olive tree (35%), house dust mites (Dermatophagoides farinae 27.5%, Dermatophagoides pteronyssinus 20.8%). In patients with only rhinitis (n= 305), the most frequent aeroallergen was pollen (grasses 43.6%; cereal mixtures 43.3%; timothy grass 41.6%; olive pollen 37.4%). In patients with asthma and rhinitis (n= 134), the most frequent aeroallergen was grass (44.8%). In patients with only asthma (n= 33), the most frequent aeroallergens were D. farinae (27.3%) and cockroach (27.3%). The most frequently detected allergens in this study were pollen, cockroach, and house dust mites, respectively. The findings revealed that pollen was the most frequent aeroallergen in subjects with allergic rhinitis with and without asthma. In patients with only asthma, the most frequent aeroallergen was house dust mites.

A New Technique for the Passive Monitoring of Particulate Matter: Olive Pollen Grains as Bioindicators of Air Quality in Urban and Industrial Areas

A new technique for the passive monitoring of particulate matter was developed, exploiting olive pollen as a bioindicator. We tested the pollen bioaccumulation efficiency when exposed to atmospheric particulate at three different sites in the Umbria region (Central Italy). Pollen grains, placed into sampling holders, were exposed in Perugia, a polluted town impacted by traffic emissions; in Terni, an industrial hotspot; and at Monte Martano, a regional rural site. At the end of the exposure period, the daily deposition fluxes of the soluble and insoluble elements and soluble molecular ions present in particulate were determined, and the bioaccumulation factor (BAF) and bioaccumulation index over time (BAIt) were derived to validate the passive monitoring system, distinguish the deposition contribute from natural pollen composition, and interpret the temporal dependence of the pollen exposure to pollutants. We observed BAFs greater than 1, which means that bioaccumulation occurs, and pollen can be considered a good passive sampler for several crustal and anthropic ions and toxic elements at all sites. BAIt values greater than 1 were detected only for some of the ions and metals previously present in the pollen, like Ca, Cr, and Mn at Terni; and nitrate, Ca, and Mn at Monte Martano and Perugia.

Transcriptomic Insight into the Pollen Tube Growth of Olea europaea L. subsp. europaea Reveals Reprogramming and Pollen-Specific Genes Including New Transcription Factors.

The pollen tube is a key innovation of land plants that is essential for successful fertilisation. Its development and growth have been profusely studied in model organisms, but in spite of the economic impact of olive trees, little is known regarding the genome-wide events underlying pollen hydration and growth in this species. To fill this gap, triplicate mRNA samples at 0, 1, 3, and 6 h of in vitro germination of olive cultivar Picual pollen were analysed by RNA-seq. A bioinformatics R workflow called RSeqFlow was developed contemplating the best practices described in the literature, covering from expression data filtering to differential expression and clustering, to finally propose hub genes. The resulting olive pollen transcriptome consisted of 22,418 reliable transcripts, where 5364 were differentially expressed, out of which 173 have no orthologue in plants and up to 3 of them might be pollen-specific transcription factors. Functional enrichment revealed a deep transcriptional reprogramming in mature olive pollen that is also dependent on protein stability and turnover to allow pollen tube emergence, with many hub genes related to heat shock proteins and F-box-containing proteins. Reprogramming extends to the first 3 h of growth, including processes consistent with studies performed in other plant species, such as global down-regulation of biosynthetic processes, vesicle/organelle trafficking and cytoskeleton remodelling. In the last stages, growth should be maintained from persistent transcripts. Mature pollen is equipped with transcripts to successfully cope with adverse environments, even though the in vitro growth seems to induce several stress responses. Finally, pollen-specific transcription factors were proposed as probable drivers of pollen germination in olive trees, which also shows an overall increased number of pollen-specific gene isoforms relative to other plants.

Allergy to cypress and olive pollen: Clinical phenotypes and allergen recognition.

Cypress and olive pollen are the most prevalent sensitizer trees in the Mediterranean area. Some patients exhibit a dual sensitization which has not been well documented yet. To identify the allergens involved in the dual cypress and olive allergy (C+O) and study the relationship between phenotype and allergen sensitization. C+O patients were selected. Monosensitized subjects to olive or cypress were used as reference. Specific IgE to whole extracts and purified allergens from olive and cypress were performed. Immunoblotting was done to analyze IgG and IgE-binding using olive polyclonal antibodies and patients' sera, respectively. Mutual immunoblotting inhibition of olive and cypress extracts, and inhibition of cypress extract immunoblotting with olive allergens were performed. Multiple correspondence analysis and hierarchical cluster classifications were conducted to analyze the relationships between C+O clinical presentation (symptoms, seasonality) and allergen profile. C+O patients were clustered in 4 phenotypes. The most frequent one (58.4%) was rhinoconjunctivitis in winter (February) and spring (May), with asthma in 38% of subjects. Ole e 1 and Cup s 1 were the major allergens. Homologous proteins to Ole e 1, Ole e 9 and Ole e 11 in cypress pollen were identified and these olive allergens inhibit IgE-binding to cypress extract. The exclusive C+O allergy results from co-sensitization to Cup s 1 and Ole e 1, and to cross-reactivity due to Ole e 1-like, Ole e 9-like and Ole e 11-like allergens not described previously, and translates into 4 clinical phenotypes of winter and/or spring or perennial rhinoconjunctivitis with and without asthma.

L’olivier, une richesse méditerranéenne au prix d’une allergie complexe

The olive tree (Olea europea L.) is a characteristic tree of Mediterranean basin countries, responsible for the most frequent pollinosis. This pollinosis is influenced by climate change, which can anticipate flowering dates, increase the quantity of pollen produced, and the pollen season length. The occurrence of olive pollinosis mainly depends on HLA class II, IL-13 and IL-4RA genes; and environment factors, such as socioeconomic and nutritional status, physical activity and exposure to different stimuli. Among deferent categories of molecular allergens involved in olive pollinosis, Ole e 1 is the main allergen, and the presence of homology between these allergens, and those of other species from the Oleaceae family and other different taxons (Poaceae), is responsible for cross-reactions. Polysensitization is a major challenge in the diagnostic and therapeutic approach and highlights the importance of using molecular allergens in the pollinosis diagnostic. Furthermore, allergy to the olive tree has nowadays benefited from progress in specific immunotherapy, thanks in particular to the development of a strategy based on allergenic peptides as an alternative to whole olive tree pollen extracts.