Neural networks for increased accuracy of allergenic pollen monitoring.

Monitoring of airborne pollen concentrations provides an important source of information for the globally increasing number of hay fever patients. Airborne pollen is traditionally counted under the microscope, but with the latest developments in image recognition methods, automating this process has become feasible. A challenge that persists, however, is that many pollen grains cannot be distinguished beyond the genus or family level using a microscope. Here, we assess the use of Convolutional Neural Networks (CNNs) to increase taxonomic accuracy for airborne pollen. As a case study we use the nettle family (Urticaceae), which contains two main genera (Urtica and Parietaria) common in European landscapes which pollen cannot be separated by trained specialists. While pollen from Urtica species has very low allergenic relevance, pollen from several species of Parietaria is severely allergenic. We collect pollen from both fresh as well as from herbarium specimens and use these without the often used acetolysis step to train the CNN model. The models show that unacetolyzed Urticaceae pollen grains can be distinguished with > 98% accuracy. We then apply our model on before unseen Urticaceae pollen collected from aerobiological samples and show that the genera can be confidently distinguished, despite the more challenging input images that are often overlain by debris. Our method can also be applied to other pollen families in the future and will thus help to make allergenic pollen monitoring more specific.

Allergenicity at component level of sub-pollen particles from different sources obtained by osmolar shock: A molecular approach to thunderstorm-related asthma outbreaks.

BACKGROUND: The so-called "thunderstorm asthma" (TA) is an uncommon but dramatic outbreak of asthma attacks occurring during a thunderstorm in the pollen and moulds season. Mechanisms which make the pollen able to enter the deeper airways and provoke severe asthma symptoms are still unclear. OBJECTIVE: To test the hypothesis that sub-pollen particles (SPPs) originated from the rupture by an osmotic shock of pollen associated with TA contain allergens. METHODS: After hydration, SPPs released from pollen grains of grass, pellitory, olive, cypress, ragweed and birch were isolated and determined by microscopy. Allergens were determined by in vitro ELISA inhibition tests indirectly using the sera from 10 polyreactive patients. An inhibition <50% was considered as negative, 50%-75% moderate and > 75% complete. RESULTS: The inhibition experiments showed that the SPPs from birch and cypress were unable to inhibit serum IgE reactivity to Bet v 1 and Cup a 1, respectively. Ragweed SPPs inhibited ragweed pollen extract and Amb a 1 by 75.8 ± 0.11% and 81.2 ± 0.15%, respectively. Olive and pellitory SPPs retained almost the whole IgE-binding capability in all cases tested. Grass SPPs inhibited 32 ± 0.06% of Lolium perenne Lol p 1 and 65% of Phleum pratense extracts, but results were highly variable for individual allergens (97.5%-0.03% for Phl p 2, 45.3 ± 0.12% for Phl p 5, 24.7 ± 0.22% for Phl p 6, and 38.3 ± 0.2% for Phl p 1). CONCLUSIONS: Inhibition experiments confirm the hypothesis that SSPs obtained after the osmotic shock of pollen involved in TA, namely grass, pellitory and olive tree pollen, contain allergens and therefore they can induce severe asthma attacks during thunderstorms.

Safety and treatment compliance of subcutaneous immunotherapy: A 30-year retrospective study.

BACKGROUND: Safety and treatment compliance are still considered important shortcomings of subcutaneous immunotherapy (SCIT). OBJECTIVE: To assess the rate of side effects (SE) to SCIT and treatment compliance at a hospital medically supervised facility. METHODS: A retrospective review of patients with allergic rhino-conjunctivitis (ARC) with or without asthma, who received SCIT to mites and pollens from 1988 to 2018, was performed. The information was collected from patient's allergen immunotherapy forms that had been prospectically filled in by expert physicians. RESULTS: Two thousand two hundred patients (50.2% males; mean age 29.4 ±â€¯11.7 years) received 3037 SCIT courses. A total of 91,187 injections were given, with a mean SCIT duration of 2.5 ±â€¯1.9 years. Nine hundred fifty-seven patients (43.5%) were compliant as they completed the minimally required treatment duration of 3 years. A total of 1087 SE (1.2% of all injections; 76.8% local reactions) were reported in 513 patients (23.3%). There were 42 anaphylactic reactions (in 29 patients) during the study period; two of these were severe. Adrenalin was administered only once. No anaphylactic shock was reported. Only 39 patients (1.8%) discontinued SCIT because of SE, the majority of whom (24; 61.5%) because of systemic reactions (urticaria, asthma, anaphylaxis). Parietaria vaccines were the most frequently associated to SE. Female gender, number of vaccines administered (2 vaccine vs. 1 vaccine) and year of SCIT inception (1996-2018 vs. 1988-1995) were independently associated to SE. CONCLUSION: SCIT, although not absolutely free of risk, is safe and well tolerated. There is still room for improvement of treatment compliance.

Antibacterial, Anticandidal, Phytochemical, and Biological Evaluations of Pellitory Plant.

Pellitory plant (Parietaria judaica (PJ)) is one of the most widely used Arabian traditional medicinal plants due to its ability to cure several infectious diseases and other illnesses. The current study is aimed at assessing the phytoconstituents, antilipase, antiamylase, antimicrobial, and cytotoxic characters of the Pellitory plant (Parietaria judaica (PJ)). Phytochemical screening and procyanidin detection were conducted according to the standard phytochemical procedures. Porcine pancreatic lipase and α-amylase inhibitory activities were carried out using p-nitrophenyl butyrate and dinitrosalicylic acid assays, respectively. In addition, antimicrobial activity was determined utilizing a microdilution assay against several bacterial and fungal strains. Besides, the cytotoxic effect against HeLa cell line was tested employing 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. The quantitative test results revealed that the methanol fraction of PJ contains 18.55 ± 0.55 mg of procyanidin and has a potential α-amylase inhibitory activity compared with the antidiabetic drug Acarbose with IC50 values of 15.84 ± 2.25 and 28.18 ± 1.22 µg/ml, respectively. Also, it has a potential antilipase activity compared to the commercial antiobesity drug, Orlistat, with IC50 values of 38.9 ± 0.29 and 12.3 ± 0.35 µg/ml, respectively. The acetone, hexane, and methanol fractions have broad-spectrum antibacterial activity against the screened bacterial strains, while the acetone fraction has shown anticandidal activity with a MIC value of 0.195 mg/ml. The PJ hexane and acetone fractions decreased HeLa cell viability significantly (p value < 0.0001) by approximately 90% at the concentration of 0.625 mg/ml. The revealed outcomes showed that the methanol fraction has strong α-amylase and lipase inhibitory characters. Besides, acetone, hexane, and methanol fractions have broad-spectrum antibacterial activity, while the acetone fraction revealed potent antifungal activity against Candida albicans. Moreover, at low concentrations, hexane and acetone fractions have potent cytotoxic and antiproliferative activity against HeLa cancer cells. Nevertheless, PJ acetone, hexane, and methanol fractions can serve as an effective source of natural products to develop new antiobesity, antidiabetic, antimicrobial, and anticancer agents.

Parietaria major allergens vs pollen in the air we breathe.

BACKGROUND: Parietaria and Urtica are the genera from the Urticaceae family more frequent in Mediterranean and Atlantic areas. Moreover, both genera share pollination periods, and their pollen (of the main species) is so similar that there is no aerobiological evidence of the proportion of each of them in the airborne pollen identification, except in the case of U. membranacea. However, Parietaria is one of the most important causes of pollinosis and Urtica is not. Our aim is determine if airborne Urticaceae pollen concentrations show the aerodynamics of the two major allergens of Parietaria (Par j 1 and Par j 2) as well as the allergen distribution in the different-sized particles. METHODS: The air was sampled during the pollination period of Urticaceae using Hirst Volumetric Sampler and Andersen Cascade Impactor in two cities of Southern Spain (Córdoba and Granada). The samples were analysed by the methodology proposed by the Spanish Aerobiology Network (REA) and the minimum requirements of the European Aeroallergen Society (EAS) for pollen, and by ELISA immunoassay for allergens. RESULTS: The patterns of airborne pollen and Par j 1-Par j 2 were present in the air during the studied period, although with irregular oscillations. Urticaceae pollen and Par j 1-Par j 2 allergens located in PM2.5 showed positive and significant correlation during the period with maximum concentrations (March to April). CONCLUSION: Parietaria aeroallergens show similar pattern of Urticaceae airborne pollen. Urticaceae pollen calendar is as a good tool for allergy prevention. On the other hand, important concentrations of Par j 1 and Par j 2 were located in the breathable fraction (PM2.5), which could explain the asthmatic symptoms in the allergic population to Parietaria.

Assessment of neural networks and time series analysis to forecast airborne Parietaria pollen presence in the Atlantic coastal regions.

Pollen forecasting models are a useful tool with which to predict episodes of type I allergenic risk and other environmental or biological processes. Parietaria is a wind-pollinated perennial herb that is responsible for many cases of severe pollinosis due to its high pollen production, the long persistence of the pollen grains in the atmosphere and the abundant presence of allergens in their cytoplasm and walls. The aim of this paper is to develop artificial neural networks (ANNs) to predict airborne Parietaria pollen concentrations in the northwestern part of Spain using a 19-year data set (1999-2017). The results show a significant increase in the length of time Parietaria pollen is in the air, as well as significant increases in the annual Parietaria pollen integral and mean daily maximum pollen value in the year. The Neural models show the ability to forecast airborne Parietaria pollen concentrations 1, 2, and 3 days ahead. A developed model with five input variables used to predict concentrations of airborne Parietaria pollen 1 day ahead shows determination coefficients between 0.618 and 0.652.

Allergy in adolescent population (14-18 years) living in Campania region (Southern Italy). A multicenter study.

Summary: Adolescents (Ad) constitute a difficult to manage population among individuals suffering from asthma. The aim of our study was to assess the prevalence, clinical characteristics and age of onset of allergic sensitization and clinical symptoms in a sample of atopic Ad living in the Campania region (Southern Italy). Sixteen Allergy units or Centers belonging to the Italian Association of Hospital and Territorial Allergologists (AAIITO, Campania region) participated in this cross-sectional study. A case report form (CRF) was specifically designed for this study and commercial allergen extracts used for screening SPTs were provided by ALK-Abelló Group (Milan, Italy). A total of 443 patients were examined (females, f 220, 49.6 %; males, m 223, 50.3%). Dust mites represent the most common sensitizing agents in allergic Ad living in Campania region (Dermatoph. pteronyssinus 67.4% and Dermatoph. farinae 66.5%), followed by Parietaria (58.9%), grasses (45.8%), Artemisia vulgaris (16.7%), Olea Europaea (32.2%), dog dander (17.1%), cat dander (20.0%), Alternaria alternata (8.1%), Cupressus sempervirens (4.9%), Betula pendula (4.7%), other allergens (19.4%). An interesting comparison has been made between clinical data of our Ad with data of elderly patients (E). The role of allergic sensitization is significantly higher in Ad compared to E. Dermatophagoides pteronyssinus is the first sensitizing allergen in Ad and the last in E. Parietaria constitutes the first sensitizing pollen both in Ad and E, the percentage of sensitization is higher in Ad. Another important difference is the higher prevalence of As, as only symptom, in E compared to Ad (19.7% versus 7.6%). In conclusion, our findings confirm the high prevalence and clinical significance of airway allergic sensitization in the adolescents living in Campania region.

Detection of profilin in SPT extracts that are supposed to contain it.

INTRODUCTION AND OBJECTIVES: Profilin is a panallergen contained in pollen, plant foods and latex. Although cross-reactivity is expected while performing skin prick tests (SPT) with allergens that contain profilin, this is not always noticed. The purpose of this study was to detect if profilin is contained in the commercial SPT extracts of pollen and plant foods which, in their fresh form, contain determined epitopes of profilin. MATERIAL AND METHODS: Commercial SPT extracts of different pharmaceuticals were analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The study included purified palm date profilin, peach (whole, pulp and peel extracts), hazelnut, Olea europea, Parietaria judaica and Phleum pratense. RESULTS: Profilin was detected in all, but peach extracts; it was neither contained in the whole peach extract nor in the ones of peel or pulp. CONCLUSION: The only accurate way to detect sensitization to profilin, while performing SPT, is the use of purified profilin extract. Even if a plant food or pollen contain an identified molecule of profilin, the relevant SPT commercial extract may not.

Parietaria Allergy: An Intriguing Challenge for the Allergist.

Parietaria pollen is the most important cause of pollen allergies in the Mediterranean area, as Parietaria is widespread in this region. Many issues are associated with Parietaria allergy, including the duration of the pollen season (many doctors in fact believe that it lasts throughout the year), pollen load (which seems to be increasing over time), the impact of age (on IgE production and symptom severity), inflammatory changes (after pollen exposure), and the choice of allergen immunotherapy (AIT). In addition, molecular diagnostics allows for the defining of a correct diagnosis, differentiating between mere sensitization and true allergy. This review considers these topics and will hopefully help the allergist in clinical practice. Parietaria allergy is an intriguing challenge for the allergist in clinical practice, but it may be adequately managed by knowing the peculiarities of respective territories and the clinical characteristics of each patient.

Tolerability and positive efficacy results after subcutaneous immunotherapy with Parietaria judaica depot extract.

AIM: To evaluate tolerability and efficacy of Parietaria judaica subcutaneous immunotherapy on patients with allergic rhinoconjunctivitis. PATIENTS & METHODS: 51 patients were assigned to build-up scheme (six increasing doses) of P. judaica depot native extract, plus three maintenance monthly administrations. RESULTS: Out of 470 administered doses, only 3.8% elicited systemic reactions (1.5% nonspecific and 2.3% grade I). Concerning the exploratory efficacy parameters: cutaneous reactivity at the final visit versus baseline was significantly decreased; specific titers of IgG and IgG4 increased significantly and patients showed a significant decrease in the rhinitis symptoms score. CONCLUSION: P. judaica subcutaneous immunotherapy (Allergovac® depot ROXALL Medicina España S.A., Zamudio, Spain) with an abbreviated up-dosing scheme showed an adequate safety and tolerability profile and induced preliminary efficacy changes.

Anaphylaxis secondary to Parietaria judaica (wall pellitory).

Aeroallergens are an unusual cause of anaphylaxis with sparse reports in the literature. We describe a case of suspected anaphylaxis to Parietaria judaica pollen and the difficulties encountered in confirming this diagnosis.

Allergic sensitization prevalence in a children and adolescent population of northeastern Greece region.

OBJECTIVES: To evaluate the prevalence of allergic sensitization in a childhood and adolescent population, to explore age- and gender-specific variations and finally to discover co-sensitivities among allergens. METHODS: A two-stage cross-sectional survey among school-aged children. The two stages of the study involved enrollment of schools and then skin prick testing (SPT) within schools. A total of 675 school children were included in the study. Of those, 231 were diagnosed with allergic rhinitis (AR), according to the medical history as provided by parental-completed questionnaires and positive SPT results. The antigen panel consisted of common allergens and more specifically house dust mites-HDM (Dermatophagoides farinae and Dermatophagoides pteronyssinus), grass mix, trees (olive, cypress and pine), weeds (Parietaria spp.), cat and dog epithelium and moulds (Alternaria spp., Cladosporium spp.). The SPT sensitivity was graded according to SPT-USA Standards. RESULTS: The overall prevalence rate of AR was 34.22%. In total, 93 school children (40.3%) were mono- and 138 (59.7%) were poly-sensitized. Overall, the most prevalent sensitizations in decreasing order were to HDM (59.74%), to grasses (48.9%), to Alternaria (34.6%) and to olive (14.71%). There were no age- and sex-specific differences, except for Alternaria mould that showed a significant prevalence among primary school-aged children and predominance in the female gender, by contrast to grass pollen allergy that was predominant to males. A 32% of SPT-positive individuals were not aware of their allergy, with no statistically significant differences between ages. Co-sensitivities were detected for grass pollens and pine and olive trees, for Alternaria and Cladosporium moulds, for cypress and pine trees, and finally for dog and cat danders. CONCLUSIONS: Given data among school-aged children should be a baseline from which to monitor disease trends and is considered important for the optimal management of AR patients.

Dimerisation increases the immunogenicity of recombinant Parj1/Parj2 allergens.

Purified recombinant Parj1 and Parj2 allergens bind an IgE repertoire common to the Parietaria species, allowing their use as marker molecules for diagnosis and therapy of allergic disease induced by the Urticaceae family. Preclinical studies on the in vivo immunogenicity of recombinant Parj1, Parj2 and their isoforms indicated differential capacity to induce IgG1 antibody responses, as indication of potential clinical use. A recombinant hetero-dimeric hybrid derivative (PjED), encompassing the shorter Parj1 isoform (Parj1.0201) and Parj2 allergen, was characterised. In vivo immunisation with PjED induces IgG1 antibodies capable of binding all the isoforms of Parietaria major allergens, overcoming the poor immunogenicity of single monomeric allergens. This feature makes PjED a promising candidate molecule to be further characterised for clinical applications in the treatment of Parietaria allergy.

Clinical bystander effect exerted by allergen immunotherapy: a hypothesis.

Allergen Immunotherapy (AIT) is able to restore a physiological Th1 response and Tregs function. This effect is allergen-specific, even though it has been reported that it may also be non-specific, such as also extended to allergens not used in AIT. This immunological phenomenon may also be of clinical nature. This case report shows that a poly-allergic patient, successfully treated with Parietaria extract, also achieved a clinical tolerance towards other causal allergens, such as mites and cat. Of course, this was an anecdote, but it is reasonable to prospect the hypothesis that a bystander clinical effect may be observed during AIT in poly-allergic patients.

Multiple IgE recognition on the major allergen of the Parietaria pollen Par j 2.

The interaction between IgE antibodies and allergens is a key event in triggering an allergic reaction. The characterization of this region provides information of paramount importance for diagnosis and therapy. Par j 2 Lipid Transfer Protein is one of the most important allergens in southern Europe and a well-established marker of sensitization in Parietaria pollen allergy. The main aim of this study was to map the IgE binding regions of this allergen and to study the pattern of reactivity of individual Parietaria-allergic patients. By means of gene fragmentation, six overlapping peptides were expressed in Escherichia coli, and their IgE binding activity was evaluated by immunoblotting in a cohort of 79 Parietaria-allergic patients. Our results showed that Pj-allergic patients display a heterogeneous pattern of IgE binding to the different recombinant fragments, and that patients reacted simultaneously against several protein domains spread all the over the molecule, even in fragments which do not contain structural features resembling the native allergen. Our results reveal the presence of a large number of linear and conformational epitopes on the Par j 2 sequence, which probably explains the high allergenic activity of this allergen.

Recent advances in immunotherapy for allergic diseases.

Allergic diseases are a major health problem worldwide. The therapeutic approaches to treat allergic rhinitis (AR) and allergic asthma (AA) fall in three major categories. The first step is allergen avoidance, or reduction of exposure to the offending allergen(s). The second and most widely used therapeutic practice is the prescription of relevant medication to reduce symptoms. The third therapeutic element is specific allergy vaccination, also known as allergen specific immunotherapy. Allergen-specific immunotherapy (SIT) is the only etiologic treatment of allergic disorders that can alter the natural course of the disease. In this review, recent advances in immunotherapy and relevant patents are presented. General vaccine modifications could be applied for any type of allergen. New specific modifications in allergic vaccines have been developed for a variety of allergies such as house dust mites, horse, cat, parvalbumin and from birch, ragweed and parietaria pollen.

Cloning, expression in E. coli and immunological characterization of Par j 3.0201, a Parietaria pollen profilin variant.

Parietaria judaica pollen is one of the main sources of allergens in the Mediterranean area. Its allergenic composition has been studied in detail showing the presence of two major allergens (Par j 1 and Par j 2) and two minor allergens belonging to the profilin and calcium binding protein families of allergens (Par j 3 and Par j 4, respectively). Clinical reports support the hypothesis of a limited cross-reactivity between profilin from Parietaria and unrelated sources. We screened a P. judaica cDNA library to identify novel forms of profilins with allergenic activity. This strategy allowed us to isolate a 767 bp cDNA containing the information for a 131 amino acids protein with homology to profilins from unrelated sources greater than that observed with the already published Parietaria profilins. This profilin was expressed in Escherichia coli as a recombinant protein and its immunological prevalence was studied in a population of Parietaria allergic patients from Southern Europe. Immunoblotting analysis showed that the Parietaria profilin was recognized by IgE from 6.5% of the allergic population. Finally, a selected population of profilin allergic patients was enrolled to demonstrate the cross-reactivity of this novel variant with other profilins from grass and date palm. In conclusion, molecular cloning and immunological studies have allowed the isolation, expression and immunological characterization of a novel cross-reactive profilin allergen from P. judaica pollen named Par j 3.0201.