Pollen Extract Research Articles

Evaluation of the protocol for rush subcutaneous immunotherapy with birch pollen extract

We previously reported the effectiveness of rush subcutaneous immunotherapy with birch pollen extract (Birch rSCIT) for pollen-food allergy syndrome (PFAS) and the high rate of systemic reactions (SR) during the rapid escalation phase. In this study, we examined whether modifying the dose escalation protocol of Birch rSCIT would reduce SR and maintain therapeutic effects. Birch rSCIT was introduced in 20 patients with PFAS who experienced systemic symptoms upon ingestion of soybeans. Birch rSCIT was implemented using 3 protocols: 2 protocols (nonstep-up group) increased the target dose to more than 1:2 × 102 (w/v) in 0.05 mL, while 1 protocol (step-up group) increased the target dose to 1:2 × 103 (w/v) in 0.3 mL, and then increased to 1:2 × 102 (w/v) in 0.05 mL using the conventional method in the following week. In the nonstep-up group, 4 out of 5 patients (80%), and in the step-up group, 2 out of 15 patients (13.3%) developed SR during rapid escalation. During the rapid escalation phase, the step-up group had significantly fewer SR than the nonstep-up group (P = 0.014). The median ingestible dose of soy milk in the oral food challenge was 3.5 mL before the treatment and increased significantly to 200 mL 1 year after initiating Birch SCIT (P < 0.01). We confirmed that reducing the target antigen dose in Birch rSCIT improved safety and maintained the therapeutic effect for soybean allergy with PFAS.

Bee pollen from bracatinga (Mimosa scabrella): Effects of gastrointestinal digestion and epithelial transport in vitro on phenolic profile and bioactivities

The main objective of the present work was to assess the phenolic profile of bracatinga (Mimosa scabrella) bee pollen, and its antioxidant and anti-inflammatory activities after gastrointestinal digestion in vitro and epithelial transport in a Caco-2 cell monolayer model. The botanical origin of bee pollen was confirmed by optical microscopy and scanning electron microscopy. As major results, 34 phenolic compounds (13 phenylamides, 14 flavonols, and 7 flavanones) were tentatively identified in the extract of bracatinga bee pollen by HPLC-ESI-QTOF-MS. The aglycone forms of quercetin and p-coumaric acid were identified only after digestion, indicating the breakage of flavonols and phenylamides, respectively. These compounds may have contributed to the decrease in NF-κΒ activation up to 54% and in the release of TNF-α and CXCL2/MIP-2 by 26% and 21%, respectively, in raw 264.7 murine macrophages activated with microbial lipopolysaccharide and treated with the digested fraction. Among all tentatively identified phenolic compounds, five of them were found in the basolateral fraction. These compounds, represented by four aglycone flavonoids (quercetin, kaempferol, naringenin, and herbacetin methyl ether) and a phenolic acid (p-coumaric acid) may be responsible for its outstanding antioxidant activity in Caco-2 cells, as well as for its remaining capacity in mitigating CXCL2/MIP-2 release after transport through the Caco-2 cell monolayer, as an intestinal barrier model. Therefore, our work sheds light on the phenolic profile and bioactivities of an interesting functional food produced by bees throughout a simulated gastrointestinal system.

Skin Prick Tests and Enzyme-Linked Immunosorbent Assays among Allergic Patients Using Allergenic Local Pollen Extracts.

Allergic respiratory diseases are prevalent in the Philippines, with allergic rhinitis and asthma occurring at 20% and 8.7% of the population, respectively. The diagnosis of respiratory allergies is achieved by a combination of patient history and different screening tools, especially for the identification of the allergic triggers such as allergy skin prick test (SPT) and serum-specific IgE enzyme-linked immunosorbent assays (sIgE ELISA). The Philippines, being a tropical country, have a wide variety of plant species with potential to produce allergenic pollen grains. Knowledge of the sensitization profiles of Filipino allergic patients to our local pollen allergens is currently limited. The aim of this study is to determine the sensitization profile of patients with respiratory allergies (allergic rhinitis and/or asthma) through the allergy skin prick test (SPT) using allergenic local pollen extracts. It also aimed to determine if there is a positive agreement between the SPT and sIgE ELISA positivity rate and whether the results have relationship with the pollen purity and the protein content of the extracts. Pollen allergens were extracted from Amaranthus spinosus (pigweed), Mimosa pudica (makahiya), Tridax procumbens (wild daisy), Imperata cylindrica (cogon), Oryza sativa (rice), Pennisetum polystachion (foxtail grass), Sorghum halepense (Johnson grass), Albizia saman (acacia), Cocos nucifera (coconut), Leucaena leucocephala (ipil-ipil), and Mangifera indica (mango). SPT was performed at the Allergy Clinic of the University of the Philippines-Philippine General Hospital on patients with allergic rhinitis and/or bronchial asthma. Blood samples were collected from patients who developed wheal diameters of 3 mm or more than the negative control. Sera were tested against the same pollen extracts using ELISA. Of the one hundred sixty-five (165) patients who submitted for skin prick test, 129 showed positive SPT results to the pollen extracts. Weeds were the most sensitizing (51.9%-58.1%). Blood samples were collected from these patients and tested for sIgE ELISA and among them, 71 were positive in the sIgE ELISA. Highest sensitization rates in sIgE ELISA were found in coconut, pigweed, Johnson grass, and rice. The highest positive agreements or the proportion of patients with positive sIgE ELISA among those with positive SPT were in coconut, followed by Johnson grass, pigweed, and rice. Most of the pollen sensitized patients on SPT are polysensitized. SPT is a safe, simple, and rapid method for the diagnosis of IgE-mediated allergy. The lower number of positive patients in sIgE ELISA may be attributed to the low serum IgE levels and low quantities of effectual allergen components in extracts. Results of both SPT and ELISA must be correlated with a patient's clinical history, particularly the patient's exposures, and physical examination.

The use of metagenomic and untargeted metabolomics in the analysis of the effects of the Lycium barbarum glycopeptide on allergic airway inflammation induced by Artemesia annua pollen

Ethnopharmacological relevanceThe prevalence of allergic airway inflammation (AAI) worldwide is high. Artemisia annua L. pollen is spread worldwide, and allergic diseases caused by its plant polysaccharides, which are closely related to the intestinal microbiota, have anti-inflammatory effects. Further isolation and purification of Lycium barbarum L. yielded its most effective component Lycium barbarum L. glycopeptide (LbGP), which can inhibit inflammation in animal models. However, its therapeutic effect on AAI and its mechanism of regulating the intestinal flora have not been fully investigated. Aim of the studyTo explore LbGP in APE-induced immunological mechanisms of AAI and the interaction mechanism of the intestinal flora and metabolites. MethodsA mouse model of AAI generated from Artemisia annua pollen was constructed, and immunological indices related to the disease were examined. A combination of macrogenomic and metabolomic analyses was used to investigate the effects of LbGP on the gut microbial and metabolite profiles of mice with airway inflammation. ResultsLbGP effectively alleviated Artemisia. annua pollen extract (APE)-induced AAI, corrected Th1/Th2 immune dysregulation, decreased Th17 cells, increased Treg cells, and altered the composition and function of the intestinal microbiota. LbGP treatment increased the number of OdoribacterandDuncaniella in the intestines of the mice, but the numble of Alistipes and Ruminococcus decreased. Metabolite pathway enrichment analysis were used to determine the effects of taurine and hypotaurine metabolism, bile acid secretion, and pyrimidine metabolism pathways on disease. ConclusionOur results revealed significant changes in the macrogenome and metabolome following APE and LbGP intervention, revealed potential correlations between gut microbial species and metabolites, and highlighted the beneficial effects of LbGP on AAI through the modulation of the gut microbiome and host metabolism.

The Impact of High-Fructose Diet and Co-Sensitization to House Dust Mites and Ragweed Pollen on the Modulation of Airway Reactivity and Serum Biomarkers in Rats.

The topic of ragweed pollen (RW) versus house dust mites (HDMs) has often been deliberated, but the increasing incidence of co-sensitization between them has been scarcely addressed. Utilizing Sprague Dawley rats, we explored the effects of co-sensitization with the combination of HDMs and RW pollen extracts in correlation with high-fructose diet (HFrD) by in vitro tracheal reactivity analysis in isolated organ bath and biological explorations. Our findings unveiled interrelated connections between allergic asthma, dyslipidemia, and HFrD-induced obesity, shedding light on their compounding role through inflammation. The increased CRP values and airway hyperresponsiveness to the methacholine challenge suggest a synergistic effect of obesity on amplifying the existing inflammation induced by asthma. One of the major outcomes is that the co-sensitization to HDMs and RW pollen led to the development of a severe allergic asthma phenotype in rats, especially in those with HFrD. Therefore, the co-sensitization to these allergens as well as the HFrD may play a crucial role in the modulation of systemic inflammation, obesity, and airway reactivity.

Identification of cross-reactive IgE-binding proteins from Philippine allergenic grass pollen extracts.

Respiratory allergies are one of the most common allergic diseases that affect Filipinos. Grass pollen accounts for the majority of the outdoor allergens triggering these respiratory allergies. Cross-reactivity among the Philippine grass pollen grains has not been extensively studied. This study aims to investigate the cross-reactivity of our local grasses and identify the cross-reactive allergens. Grass pollen grains were collected and processed into crude allergenic extracts. The IgE-reactivity of these crude allergenic pollen extracts was studied using sera from patients who tested positive for the mentioned extracts. The proteins from the immunoblots of cross-reactive pollen allergen extracts were sequenced and identified. Allergenic pollen proteins were identified as cross-reactive among the grass pollen extracts. Four of these have not been listed yet as grass allergens in the World Health Organization/International Union of Immunological Societies allergen nomenclature database. Local grass pollen allergens are cross-reactive with probable new allergens identified.

Co-sensitizations to Gibberellin Regulated Proteins (GRPs) in Italy: results of a polycentric study.

Background. Gibberellin Regulated Proteins (GRPs) are small glycoproteins that induce allergy to various types of fruit. This study aimed to evaluate co-sensitization to cypress pollen and other molecules responsible for fruit allergy, such as nsLTP (Pru p 3), PR-10 (Bet v1), and Profilin (Bet v2). Methods. Sixty subjects sensitized to peach GRP (Pru p 7) were consecutively recruited from four Italian centers: 28 males and 32 females (mean age 37.9 years; range 11-79). Specific IgE for Pru p 7, Pru p 3, Bet v 1, Bet v 2, cypress pollen extract (Cup s), and Cup a 1 were determined in all subjects. Results. Sensitization rates to Cup s, Cup a 1, Pru p 3, Bet v 1, and Bet v 2 in the entire studied population were 90.0%, 83.3%, 45.8%, 40.0%, and 30.0%, respectively. In subjects residing in Northern Italy, the respective sensitization rates were 96.4%, 80.0%, 50.0%, 73.3%, and 40.0%, while in those residing in Southern Italy, they were 83.3%, 86.7%, 40.0%, 6.7%, and 20.0%. The only significant difference was observed for PR-10 (p less than 0.0001) Co-sensitization to PR-10 was found to be associated with a reduced risk of anaphylaxis (OR: 0.125). Allergic reactions were most commonly triggered by peach (26/40), followed by orange (12/40), with other foods being less frequently implicated. Conclusions. This study confirms a high association between sensitization to Pru p 7 and cypress pollen and highlights a high percentage of co-sensitization to nsLTP, PR-10, and profilin. PR-10 emerged as a protective factor against anaphylaxis.

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.

Antioxidant, Antitumoral, Antimicrobial, and Prebiotic Activity of Magnetite Nanoparticles Loaded with Bee Pollen/Bee Bread Extracts and 5-Fluorouracil.

The gut microbiota dysbiosis that often occurs in cancer therapy requires more efficient treatment options to be developed. In this concern, the present research approach is to develop drug delivery systems based on magnetite nanoparticles (MNPs) as nanocarriers for bioactive compounds. First, MNPs were synthesized through the spraying-assisted coprecipitation method, followed by loading bee pollen or bee bread extracts and an antitumoral drug (5-fluorouracil/5-FU). The loaded-MNPs were morphologically and structurally characterized through transmission electron microscopy (TEM), selected area electron diffraction (SAED), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Dynamic Light Scattering (DLS), and thermogravimetric analysis. UV-Vis spectroscopy was applied to establish the release profiles and antioxidant activity. Furthermore, the antibacterial and antitumoral activity of loaded-MNPs was assessed. The results demonstrate that MNPs with antioxidant, antibacterial, antiproliferative, and prebiotic properties are obtained. Moreover, the data highlight the improvement of 5-FU antibacterial activity by loading on the MNPs' surface and the synergistic effects between the anticancer drug and phenolic compounds (PCs). In addition, the prolonged release behavior of PCs for many hours (70-75 h) after the release of 5-FU from the developed nanocarriers is an advantage, at least from the point of view of the antioxidant activity of PCs. Considering the enhancement of L. rhamnosus MF9 growth and antitumoral activity, this study developed promising drug delivery alternatives for colorectal cancer therapy.

Efficacy and safety of subcutaneous immunotherapy with polymerized allergen mixtures in polyallergic patients – ARES observational study

ABSTRACT Background Administration of allergen mixtures of many components comprises the most common approach for American allergists regarding the management of polyallergic patients. European allergists, however, are more reluctant to this type of treatment due to the potential drawbacks of mixing extracts. Research design and methods To assess the efficacy and safety of subcutaneous immunotherapy (SCIT) with polymerized allergen mixtures without dilutional effect in polyallergic patients. This observational, prospective, multicenter study included patients (between 5 and 60 years) with respiratory allergic diseases that had been prescribed with SCIT with mixtures of two pollen or mite extracts. Changes in Symptoms and Medication Score (SMS) and in rhinitis quality of life questionnaire (RQLQ), subjective clinical improvement, treatment satisfaction and tolerability were assessed after the 1-year treatment. Results A total of 115 patients were included in the assessment. Mean global SMS decreased from 3.5 (SD = 1.1) to 1.6 (SD = 1.2) points, with a mean absolute reduction of 1.6 (SD = 1.3) points in the RQLQ score (p < 0.001, Wilcoxon test). General subjective clinical improvements and a good treatment satisfaction and tolerability were observed. Conclusion SCIT with polymerized allergen mixtures from either pollen or mite extracts proved to be an effective and safe treatment option for polyallergic patients suffering from allergic respiratory diseases.

Functional characterization of complete and immunodominant epitopes of a novel pollen allergen from Parthenium hysterophorus.

Background. Parthenium hysterophorus pollen induces chronic clinical conditions such as allergic rhinitis and bronchial asthma. Among the plethora of proteins in the pollens, only few were reported to induce allergy. Currently sensitization to P. hysterophorus pollen allergen is diagnosed by skin prick test (SPT) using the entire pollen extract instead of using the specific allergen. Methods. In P. hysterophorus sensitized patients, SPT was done using the crude pollen extract, 40 kDa allergenic pollen protein and two commercially synthesized allergen epitopes (17 and 24) of P. hysterophorus. Dot-blot of allergen epitopes was done using P. hysterophorus sensitized sera. Crude pollen extract (1, 1.25, 2.5, 5 and 10 µg/mL), 40 kDa allergenic protein (3 µg/mL), and allergen epitopes (3µg/mL) were used to perform Basophil Activation Test (BAT). Results. Crude pollen extract at 2.5, 5, 10 μg/mL and 40 kDa allergenic protein at 3μg/mL concentrations induced wheal and flare reaction by around 15 minutes, whereas commercially synthesized allergen epitopes at 3μg/mL induced wheal and flare reactions in less than 10 minutes. Allergen epitopes (3 µg/mL) revealed strong reactivity with sensitized patient's IgE in dot-blot analysis. Basophil activation Test using crude pollen extract (2.5, 5, 10 µg/mL), 40 kDa allergenic protein (3 µg/mL), and allergenic epitopes (3µg/mL) indicated significant basophil activation (as measured by CD63 expression) in sensitized patients. Conclusions. The 40 kDa allergenic protein and its allergenic epitopes (17 and 24) induced phenotypic and cellular immune responses in P. hysterophorus sensitized individuals. The tested allergenic epitopes (17 and 24) induced faster wheal and flare reactions in comparison with the crude extract and the 40 kDa allergenic protein. The novel 40kDa allergenic protein and its allergen epitopes identified here may be useful for the development of component-resolved diagnosis (CRD) while also serving as a potential therapeutic lead for desensitization treatment for P. hysterophorus pollen induced allergy.

A Comparative Study of Egyptian Bee Pollen and Propolis Extracts: Impacts on Metabolic Profile, Liver, and Kidney Functions in Diabetic Rats Induced by Streptozotocin

A Comparative Study of Egyptian Bee Pollen and Propolis Extracts: Impacts on Metabolic Profile, Liver, and Kidney Functions in Diabetic Rats Induced by Streptozotocin

Ultrasonic assisted extraction of water-soluble vitamins from minor components of bee pollen with deep eutectic solvents (DESs) as green solvent

In this study, different deep eutectic solvents (DESs) were used for vitamin extraction from bee pollen. The DES combination with the highest total amount of individual vitamins was choline chloride: ethylene glycol (molar ratio 1:2). The response surface method was then used to optimize the extraction conditions. The independent variables used for optimization were ultrasonic power, time, and temperature, while the dependent variables were the total individual amino acids, total individual phenolic compounds, and total individual vitamin contents. Spectrophotometric analyses and antimicrobial activity were also determined in the extracts. In addition, AGREEprep, ComplexGAPI and BAGI tools were used to evaluate the greenness of the method. The results obtained with DES were compared with water, ethanol, and methanol extracts, which were considered control groups. As a result of optimization, the optimum conditions were found to be 75 % for ultrasonic power, 71.5 min for sonication time, and 40 °C for ultrasonic bath temperature. The model’s composite desirability value (d) was found to be 0.81. The predicted value and the experimental values were close to each other. Furthermore, the most dominant vitamin in DES extracts was ascorbic acid, the most dominant amino acid was proline, and the most dominant phenolic compound was myricetin. The amounts of these compounds were higher than those obtained from water, ethanol, and methanol extracts. The spectrophotometric analysis results obtained higher yields with DES compared to the control groups. Antimicrobial activity analysis showed that pollen extracts prepared using choline chloride: ethylene glycol had a weak inhibitory effect for Gram-positive and Gram-negative bacteria but not yeast-like fungal strains. In conclusion, DES has been successfully used to extract vitamins and other bioactive compounds from bee pollen. The results obtained showed that DESs can be an alternative to organic solvents for the extraction of vitamins, which are among the minor components of bee pollen. Besides, the potential of the application different DESs for more efficient extraction of vitamins and components with important pharmaceutical properties from bee pollen needs to be evaluated in detail.

Chronic inflammation in benign prostatic hyperplasia: Pathophysiology and treatment options.

Benign prostatic hyperplasia, a prevalent condition in aging men, is characterized by the proliferation of prostatic epithelial and stromal cells, which leads to bladder outlet obstruction and the exacerbation of lower urinary tract symptoms. There is increasing evidence that chronic prostatic inflammation contributes to the pathogenesis and progression of benign prostatic hyperplasia. This review explores the complex relationship between chronic inflammation and benign prostatic hyperplasia, focusing on the underlying mechanisms, clinical implications, and current therapeutic approaches. The pathophysiology of benign prostatic hyperplasia is multifaceted, involving factors such as hormonal changes, hypoxia, urine reflux into prostatic ducts and stroma, autoimmune responses, and infection-induced inflammation. Inflammatory cytokines, particularly interleukin-17 and interleukin-8, may play key roles in tissue remodeling and smooth muscle contraction within the prostate, thereby influencing benign prostatic hyperplasia progression. Current therapies for benign prostatic hyperplasia include α1-blockers, phosphodiesterase 5 inhibitors, 5α-reductase inhibitors, and plant-based treatments (e.g., pollen extract). These therapies aim to alleviate symptoms by reducing prostatic inflammation, improving blood flow, and inhibiting hormonal pathways involved in prostatic enlargement. However, patients with chronic prostatic inflammation often experience more severe lower urinary tract symptoms and may be resistant to conventional treatments. This resistance has prompted the exploration of alternative therapies targeting inflammation. Chronic prostatic inflammation plays a central role in the pathogenesis and severity of benign prostatic hyperplasia. An understanding of its mechanisms will enable the development of more effective treatments to improve the quality of life among patients with benign prostatic hyperplasia.

In ovo injection of bee pollen extract on hatchability, chick quality, glycogen reserves and production performance in broiler chickens

This study aimed to investigate the effects of in ovo injection of bee pollen (BP) extract on some hatching traits, glycogen reserves and production performance in broilers. A total of 886 eggs was randomly assigned to 5 treatments: the 0.9% NaCl diluent-injected control group, and the groups that were injected with BP extract at 3 different concentrations: BP-1.5%, BP-2.5% and BP-5.0% (7, 12 and 25 mg/egg, respectively). The last group received a carbohydrate solution (CS). At 18 d of incubation, 500 µL of each solution was injected into the air sac of each egg of the injected groups. After hatching, a total of 570 one-day-old chicks were distributed into 5 groups (in ovo injection) with 3 replicates with 38 birds. The in ovo injection of BP at a dose of 5% and CS resulted in lower hatching rates (P < 0.05) as compared with the control group. The level of glycogen in the muscle tissue of newly hatched birds was not significantly different (P > 0.05). Supplementation of embryos with BP extract also caused a significant increase in the length of chicks in the BP-1.5% group (P < 0.001). Hatched chicks from the injected eggs had a lower liver glycogen content than that of the control. Based on the results, it was concluded that high-quality day-old chicks could be obtained by in ovo injection. Supplementation of chicks with 1.5% BP extract had a beneficial effect on BW during the first rearing period and showed a hypocholesterolemic effect in young chicks. At the same time, an adverse effect of a high dose of BP (5%) and a carbohydrate solution administered in ovo on the hatchability level of chicks was shown. The implementation of the carbohydrate mixture resulted in a deterioration of biochemical indices in the plasma of newly hatched chicks, especially in the case of transaminase activity.

Identification and Characterization of Pectate Lyase as a Novel Allergen in Artemisia sieversiana Pollen

Introduction: Artemisia species are widely spread in north hemisphere. Artemisia sieversiana pollen is one of the common pollen allergens in the north of China. At present, seven allergens were identified and had been listed officially from A. sieversiana pollen, but the remaining allergens are still insufficiently studied, which need to be found. Methods: Pectate lyase was purified from the extracts of A. sieversiana pollen by anion exchange, size exclusion, and HPLC-hydrophobic interaction chromatography. The gene of A. sieversiana pectate lyase (Art si pectate lyase) was cloned and expressed in Escherichia coli. The enzyme activity and circular dichroism (CD) spectrum of natural and recombinant proteins were analyzed. The allergenicity of Art si pectate lyase was characterized by enzyme-linked immunosorbent assay (ELISA), Western blot, inhibition ELISA, and basophil activation test. The allergen’s physicochemical properties, three-dimensional structure, sequence profiles with homologous allergens and phylogenetic tree were analyzed by in silico methods. Results: Natural Art si pectate lyase (nArt si pectate lyase) was purified from A. sieversiana pollen extracts by three chromatographic strategies. The cDNA sequence of Art si pectate lyase had a 1191-bp open reading frame encoding 396 amino acids. Both natural and recombinant pectate lyase (rArt si pectate lyase) exhibited similar CD spectrum, and nArt si pectate lyase had higher enzymatic activity. Moreover, the specific immunoglobulin E (IgE) binding rate against nArt si pectate lyase and rArt si pectate lyase was determined as 40% (6/15) in patients’ serum with Artemisia species pollen allergy by ELISA. The nArt si pectate lyase and rArt si pectate lyase could inhibit 76.11% and 47.26% of IgE binding activities to the pollen extracts, respectively. Art si pectate lyase was also confirmed to activate patients’ basophils. Its structure contains a predominant motif of classic parallel helical core, consisting of three parallel β-sheets, and two highly conserved features (vWiDH, RxPxxR) which may contribute to pectate lyase activity. Moreover, Art si pectate lyase shared the highest sequence identity of 73.0% with Art v 6 among currently recognized pectate lyase allergen, both were clustered into the same branch in the phylogenetic tree. Conclusion: In this study, pectate lyase was identified and comprehensively characterized as a novel allergen in A. sieversiana pollen. The findings enriched the allergen information for this pollen and promoted the development of component-resolved diagnosis and molecular therapy of A. sieversiana pollen allergy.

Pollen products collected from honey bee hives experiencing minor stress have altered fungal communities and reduced antimicrobial properties.

Fungi are increasingly recognised to play diverse roles within honey bee hives, acting as pathogens, mutualists, and commensals. Pollen products, essential for hive nutrition, host significant fungal communities with potential protective and nutritional benefits. In this study, we profile the fungal communities and antifungal properties of three pollen products from healthy and stressed hives: fresh pollen collected by forager bees from local plants; stored pollen packed into the comb inside the hive; and bee bread, which is stored pollen following anaerobic fermentation used for bee and larval nutrition. Using amplicon sequencing, we found significant differences in fungal community composition, with hive health and sample type accounting for 8.8% and 19.3% of variation in beta diversity, respectively. Pollen and bee bread extracts had species-specific antimicrobial activity and inhibited the fungal hive pathogens Ascosphaera apis, Aspergillus flavus, and Aspergillus fumigatus, and the bacterial hive pathogen Paenibacillus larvae. Activity was positively correlated with phenolic and antioxidant content and was diminished in stressed hives. The plant source of pollen determined by amplicon sequencing differed in stressed hives, suggesting altered foraging behaviour. These findings illustrate the complex interplay between honey bees, fungal communities, and hive products, which should be considered in hive management and conservation.

NLRP3 promotes allergic responses to birch pollen extract in a model of intranasal sensitization.

Allergic sensitization is an essential step in the development of allergic airway inflammation to birch pollen (BP); however, this process remains to be fully elucidated. Recent scientific advances have highlighted the importance of the allergen context. In this regard, microbial patterns (PAMPs) present on BP have attracted increasing interest. As these PAMPs are recognized by specialized pattern recognition receptors (PRRs), this study aims at investigating the roles of intracellular PRRs and the inflammasome regulator NLRP3. We established a physiologically relevant intranasal and adjuvant-free sensitization procedure to study BP-induced systemic and local lung inflammation. Strikingly, BP-sensitized Nlrp3-deficient mice showed significantly lower IgE levels, Th2-associated cytokines, cell infiltration into the lung, mucin production and epithelial thickening than their wild-type counterparts, which appears to be independent of inflammasome formation. Intriguingly, bone-marrow chimera revealed that expression of NLRP3 in the hematopoietic system is required to trigger an allergic response. Overall, this study identifies NLRP3 as an important driver of BP-induced allergic immune responses.

Birch pollen-induced signatures in dendritic cells are maintained upon additional cytomegalovirus exposure

During the birch pollen season an enhanced incidence of virus infections is noticed, raising the question whether pollen can affect anti-viral responses independent of allergic reactions. We previously showed that birch pollen-treatment of monocyte-derived dendritic cells (moDC) enhances human cytomegalovirus (HCMV) infection. Here we addressed how in moDC the relatively weak pollen response can affect the comparably strong response to HCMV. To this end, moDC were stimulated with aqueous birch pollen extract (APE), HCMV, and APE with HCMV, and transcriptomic signatures were determined after 6 and 24 h of incubation. Infection was monitored upon exposure of moDC to GFP expressing HCMV by flow cytometric analysis of GFP expressing cells.Principle component analysis of RNA sequencing data revealed close clustering of mock and APE treated moDC, whereas HCMV as well as APE with HCMV treated moDC clustered separately after 6 and 24 h of incubation, respectively. Communally induced genes were detected in APE, HCMV and APE with HCMV treated moDC. In APE with HCMV treated moDC, the comparably weak APE induced signatures were maintained after HCMV exposure. In particular, NF-κB/RELA and PI3K/AKT/MAPK signaling were altered upon APE with HCMV exposure. Earlier, we discovered that NF-κB inhibition alleviated APE induced enhancement of HCMV infection. Here we additionally found that impairment of PI3K signaling reduced HCMV infection in HCMV and APE with HCMV treated moDC.APE treated moDC that were exposed to HCMV show a unique host gene signature, which to a large extent is regulated by NF-κB activation and PI3K/AKT/MAPK signaling.

Histological and Immunohistochemical Study of the Possible Protective Effect of Bee Pollen Extract on the Cerebellar Cortex of Valproic Acid-Induced Experimental Model of Autism in Albino Rat Pups.

Histological and Immunohistochemical Study of the Possible Protective Effect of Bee Pollen Extract on the Cerebellar Cortex of Valproic Acid-Induced Experimental Model of Autism in Albino Rat Pups.