Grass Pollen Allergic Patients Research Articles

Nanofluidic point-of-care IgE test for subtropical grass pollen for rapid diagnosis of allergic rhinitis

BackgroundWidening of subtropical climate zones globally and increasing grass-pollen exposure provide the impetus for developing a more precise and accessible diagnosis of allergy. ObjectiveTo evaluate the utility of recombinant allergen components of Panicoideae and Chloridoideae pollens for specific IgE testing in a rapid, point-of-care device. MethodsRecombinant (r) Pas n 1 and Cyn d 1 were expressed, purified, and tested in the nanofluidic device for measuring serum specific IgE (spIgE) in a well-characterized Australian cohort. Concentrations and classes of spIgE to rPas n 1 and rCyn d 1, and total IgE were compared with skin prick test results and spIgE with grass pollen. ResultsCorrelations between commercial and academic laboratories for 21 sera were high for rPas n 1 spIgE (r = 0.695) and total IgE (r = 0.945). Higher spIgE to rPas n 1 and rCyn d 1 fluorescence was detected in the patients with grass-pollen allergy and with clinician-diagnosed allergic rhinitis (n = 134) than in participants with other allergies (n = 49) or no allergies (n = 23). Correlation between spIgE concentrations to rPas n 1 (r = 0.679) and rCyn d 1 (r = 0.548), with Bahia and Bermuda grass-pollen spIgE, respectively, was highly significant (p<0.0001). The positive/negative predictive agreements of spIgE classes for rPas n 1 (73%/82.5%) and rCyn d 1 (67.8%/66.3%) between the nanofluidic and ImmunoCAP measurements for Bahia and Bermuda grass pollen, respectively, were substantial. ConclusionPoint-of-care nanofluidic tests for spIgE to rPas n 1 and rCyn d 1 could increase access to more precise clinical diagnosis for patients with allergies in subtropical regions.

Skin Physiology, Mucosal Functions, and Symptoms Are Modulated by Grass Pollen and Ozone Double Exposure in Allergic Patients

Introduction: Along with climate changes, we see an increase in allergic symptoms and the number of pollen-allergic patients in many countries. Increased allergic symptoms are associated with an elevated ozone exposure which may be linked by impaired epithelial barrier function. This study aimed to quantify the clinical effect of ozone and pollen double exposure (DE). We tested whether ozone impairs barrier-related skin physiology and mucosal functions under DE with pollen in grass pollen-allergic patients versus healthy controls. Methods: This case-control study included 8 grass pollen-allergic patients and 8 non-allergic healthy subjects exposed to grass pollen and ozone in the GA²LEN pollen chamber, comparing shorter and longer DE duration. Non-invasive skin physiological parameters were assessed, including stratum corneum hydration, skin redness, surface pH, and basal transepidermal water loss as a parameter for epidermal barrier function. The subjects’ general well-being, bronchial, nasal, and ocular symptoms were documented. Results: Skin physiology tests revealed that DE in allergic patients deteriorates the epidermal barrier function and increases the surface pH and skin redness. DE significantly induced nasal secretion in pollen-allergic versus healthy subjects, which was more pronounced with longer DE. The general well-being was significantly impaired under DE versus pollen or ozone alone, with a negative influence of DE duration. No relevant bronchial symptoms were recorded. Conclusion: Skin physiology and nasal mucosal symptoms are negatively affected by ozone and grass pollen DE in allergic patients. The negative effects showed, in some parameters, a dose (time)-response relationship. The pH can be regarded as a possible modulatory mechanism.

Quality of life in allergic rhinitis patients treatedwith intralymphatic immunotherapy (ILIT): A19-year follow-up.

In 2002-2005, we conducted a phase I/II clinical trial where a new allergy immunotherapy (AIT) route was introduced: intralymphatic immunotherapy (ILIT). Ultrasound guidance allowed injection of allergen directly into inguinal lymph nodes. Grass pollen-allergic patients received 3 injections with 1-month intervals. The short ILIT was more patient-friendly, required lower dosing, and was comparable with SCIT regarding short-term efficacy, which was used as a reference. Nineteen years after ILIT, the same patients were followed up to assess the long-term effect on quality of life and efficacy of the treatment. Patients who received ILIT and SCIT in 2002-2005 and an additional group of patients, who completed SCIT in 2015-2018, were recruited. All participants received a trial-specific in-house questionnaire and a standardized Rhinoconjunctivitis Quality of Life Questionnaire. Data were recorded off- (February 2021) and on- (May-June 2021) season. Descriptive statistics were applied. Of 58 and 54 patients who originally received ILIT or SCIT, 25 (43%) and 29 (54%) patients, respectively, returned the questionnaires for analysis. Four (16%) and 3 (11%) of the ILIT and SCIT patients, respectively, developed complete protection against grass pollen-mediated rhinitis, whereas another 15 (60%) and 20 (69%) expressed satisfaction with the received AIT. In both groups, any persistent symptoms were reported as mild. Medication usage in the ILIT and SCIT groups was comparable. Nineteen (76%) and 23 (79%) patients, respectively, expressed satisfaction with their AIT. Grass pollen ILIT leads to long-term significant improvement in rhinitis-associated quality of life 19 years after treatment, and the ILIT quality-of-life effect was not inferior to that of SCIT.

Comparison of perennial and preseasonal allergoid immunotherapy in grass pollen allergic patients.

The clinical and immunological efficacy of preseasonal allergoid immunotherapy has been previously investigated, however, studies comparing the effectiveness of the two protocols are limited in the literature. The aim of this study is to compare the clinical and immunological efficacy of pre-seasonal and perennial allergoid immunotherapy. This is a prospective cross sectional two-arm study. During the season; symptom and medication scores were filled. Before and at the end of the season; RQLQ was applied, Phl p sIgE, sIgG4 and IL-10 levels were measured. In preseasonal group patients had better symptom control for most of the weeks, particularly during the peak pollen period (April: w-2 & w-4, p = 0.04; May: w-2, p = 0.02; June: w-1, w-2, p = 0.02; w-3, w-5, p = 0.03; July: w-2, p = 0.01; w-3, p = 0.02; w-4, p = 0.04). In the perennial group, sIgG4 [1st time point: preseasonal 0.02 mgA/L vs perennial 0.13 mgA/L (p < 0.0001); 2nd time point: preseasonal 0.52 mgA/L vs perennial 0.33 mgA/L; 3rd time point: preseasonal 0.04 mgA/L vs perennial 0.12 mgA/L (p < 0.0001)] and IL-10 (1st time point: preseasonal 1.45 pg/ml vs perennial 2.03 pg/ml; 2nd time point: preseasonal 2.29 pg/ml vs perennial 2.19 pg/ml; 3rd time point: preseasonal 2.32 pg/ml vs perennial 2.16 pg/ml) levels were higher and more stable. Preseasonal immunotherapy provided better control of symptoms throughout the pollen season. However, the blocking antibody response was stronger and more permanent in the perennial immunotherapy group.

Comparison of perennial and preseasonal allergoid immunotherapy in grass pollen allergic patients.

Few studies have examined the effect of atopic dermatitis (AD) on the resolution of food allergies in Asia, and the predictors of egg allergy resolution are not yet well defined. We evaluated whether AD severity could predict the resolution of egg allergy. This retrospective cohort study included infants under 24 months of age diagnosed with IgE-mediated egg white allergy. We included subjects who completed a 60-month follow-up. Open oral food challenges (OFCs) and serologic tests were performed at the time of initial diagnosis and at 36 ± 3 and 60 ± 3 months. We analyzed 68 patients (39 boys and 29 girls). OFCs were performed in 88.2% of the patients. The egg allergy remission rates were 23.5% and 47.1% by 3 and by 5 years of age, respectively. Persistent egg allergy was significantly associated with moderate to severe AD and house dust mite sensitization. Kaplan-Meier curve analysis revealed that patients with moderate to severe AD had higher persistent egg allergy rates than patients with no and mild AD (p = 0.012). Multivariable analysis identified moderate to severe AD as strongly associated with persistent egg allergy (p = 0.001). In this study, 47.1% of infants had resolved egg white allergies at 60 months. Moderate to severe AD may be a practical and important prognostic factor for persistent egg allergy in clinical settings.

Correlation of the combined symptom and medication score with quality of life, symptom severity and symptom control in allergic rhinoconjunctivitis.

BackgroundThe European Academy of Allergy and Clinical Immunology recommended the Combined Symptom and Medication Score (CSMS) as primary endpoint in clinical trials on allergen‐specific immunotherapy (AIT) in allergic rhinoconjunctivitis. Here, the correlation between the CSMS and the validated standardised Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ(S)), Rhinitis Control Assessment Test (RCAT) and Visual Analogue Scale (VAS) was analysed.MethodsTwo prospective, multicentre, non‐interventional studies on tree pollen, grass pollen and house dust mite allergic patients were performed. The first study comprised 167 patients receiving AIT (AIT population), and the second included 56 patients treated with symptomatic medication only (control population). For up to two seasons (pollen)/exposure periods (house dust mites), participants documented their symptoms and medication intake in a CSMS diary, including VAS. In addition, the standardised RQLQ(S) and the RCAT were completed during study visits.ResultsComparison between CSMS and RQLQ(S) revealed a positive correlation in the AIT population (r = 0.426) and in the control population (r = 0.569). For CSMS and RCAT, a negative correlation with r = −0.409 (AIT) and r = −0.547 (control) was shown. Positive correlation between CSMS and VAS was also demonstrated with r = 0.585 (AIT) and r = 0.563 (control).ConclusionThese results support the assumption that the CSMS correlates with quality of life, symptom severity and symptom control on the one hand, while the moderate strength of correlations on the other hand mirrors distinctions of the CSMS compared to the assessments used here.

Ex Vivo Immunomodulatory Effects of Lactobacillus-, Lacticaseibacillus-, and Bifidobacterium-Containing Synbiotics on Human Peripheral Blood Mononuclear Cells and Monocyte-Derived Dendritic Cells in the Context of Grass Pollen Allergy

Sensing of the intestinal microbiota by the host immune system is important to induce protective immune responses. Hence, modification of the gut microbiota might be able to prevent or treat allergies, mediated by proinflammatory Th2 immune responses. The aim was to investigate the ex vivo immunomodulatory effects of the synbiotics Pollagen® and Kallergen®, containing the probiotic bacterial strains Lactobacillus, Lacticaseibacillus and Bifidobacterium, in the context of grass pollen allergy. Peripheral blood mononuclear cells (PBMCs) from grass pollen–allergic patients and healthy controls were stimulated with grass pollen extract (GPE) and synbiotics and Gata3 expression and cytokine secretion analyzed. Monocyte-derived dendritic cells (MoDCs) cells were matured in the presence of GPE and synbiotics, co-cultured with autologous naïve T cells and maturation markers and cytokine secretion analyzed. GPE stimulation of PBMCs from grass pollen–allergic patients resulted in a significant higher production of the Th2 cytokines IL-4, IL-5, IL-9 and IL-13 compared to healthy controls. Gata3+CD4+ T cell induction was independent of the allergic status. The synbiotics promoted IL-10 and IFN-γ secretion and downregulated the GPE-induced Th2-like phenotype. Co-culturing naïve T cells with MoDCs, matured in the presence of GPE and synbiotics, shifted the GPE-induced Th2 cytokine release towards Th1-Th17-promoting conditions in allergic subjects. The investigated synbiotics are effective in downregulating the GPE-induced Th2 immune response in PBMCs from grass pollen–allergic patients as well as in autologous MoDC-T cell stimulation assays. In addition to increased IL-10 release, the data indicates a shift from a Th2- to a more Th1- and Th17-like phenotype.

Sputum microRNA-screening reveals Prostaglandin EP3 receptor as selective target in allergen-specific immunotherapy.

Several microRNAs (miRs) have been described as potential biomarkers in liquid biopsies and in the context of allergic asthma, while therapeutic effects on the airway expression of miRs remain elusive. In this study, we investigated epigenetic miR-associated mechanisms in the sputum of grass pollen-allergic patients with and without allergen-specific immunotherapy (AIT). Induced sputum samples of healthy controls (HC), AIT-treated and -untreated grass pollen-allergic rhinitis patients with (AA) and without asthma (AR) were profiled using miR microarray and whole-transcriptome microarray analysis of the same samples. miR targets were predicted in silico and used to identify inverse regulation. Local PGE2 levels were measured using ELISA. Two hundred and fifty ninemiRs were upregulated in the sputum of AA patients compared with HC, while only one was downregulated. The inverse picture was observed in induced sputum of AIT-treated patients: while 21miRs were downregulated, only 4miRs were upregulated in asthmatics upon AIT. Of these 4miRs, miR-3935stood out, as its predicted target PTGER3, the prostaglandin EP3 receptor, was downregulated in treated AA patients compared with untreated. The levels of its ligand PGE2 in the sputum supernatants of these samples were increased in allergic patients, especially asthmatics, and downregulated after AIT. Finally, local PGE2 levels correlated with ILC2 frequencies, secreted sputum IL-13levels, inflammatory cell load, sputum eosinophils and symptom burden. While profiling the sputum of allergic patients for novel miR expression patterns, we uncovered an association between miR-3935 and its predicted target gene, the prostaglandin E3 receptor, which might mediate AIT effects through suppression of the PGE2 -PTGER3 axis.

Personalized Pollen Monitoring and Symptom Scores: A Feasibility Study in Grass Pollen Allergic Patients

Background: Pollen is a major trigger for allergic symptoms in sensitized individuals. Airborne pollen is usually monitored by Hirst type pollen samplers located at rooftop level, providing a general overview of the pollen distribution in the larger surroundings. In this feasibility study, grass pollen-sensitized subjects monitored the pollen in their direct environment using a portable pollen sampler (Pollensniffer) and scored their symptoms, to study the relation between symptom severity and personal grass pollen exposure. For comparison the symptoms were also correlated with pollen collected by the rooftop sampler.Methods: After recruitment 18 participants were screened for grass pollen specific (GP-sIgE) of which 12 were eligible. Nine participants completed the study (May, 2018). They were asked to monitor personal pollen exposure using a Pollensniffer on their way to school, work or other destination, and to score their symptoms via a mobile app on a scale from 0 to 10. Daily pollen concentrations were collected by a Hirst type sampler at rooftop level. Pollen grains were analyzed using a microscope.Results: Three of the four participants with high GP-sIgE (≥9.6 kU/l) reported high symptom scores (>4) and an analysis showed a significant correlation (CC) between eye, nose, and lung symptoms and the grass pollen counts collected by the Pollensniffer, as well as the daily grass pollen concentrations monitored by the rooftop sampler (CC≥0.54). In contrast, the participants with low GP-sIgE levels (<9.6 kU/l) reported low symptom scores (≤4) and often other sensitizations were present. For these subjects, no significant positive correlations (CC<0.3) of symptoms with either grass pollen collected by the personal or the rooftop sampler were found.Conclusion: The results of this feasibility study suggest that correlations between the severity of clinical symptoms of grass pollen allergic patients, and grass pollen counts as determined by the Pollensniffer or a rooftop sampler, is restricted to patients with high GP-sIgE levels, high symptom scores, and no relevant other sensitizations. Based on the low numbers of subjects with severe symptoms included in this feasibility study, no conclusions can be drawn on the performance of the Pollensniffer in relating symptoms and pollen exposure in comparison with the rooftop sampler.Trial Registration: The study was approved by the Committee Medical Ethics of the LUMC (approval numbers: NL63953.058.17/ P17.304).

Crystal structure of timothy grass allergen Phl p 12.0101 reveals an unusual profilin dimer

Timothy grass pollen is a source of potent allergens. Among them, Phl p 1 and Phl p 5 are thought to be the most important, as a majority of timothy grass-allergic individuals have IgE antibodies directed against these two allergens. The profilin from timothy grass (Phl p 12) has been registered as a minor allergen, with up to 35% of individuals in populations of grass pollen allergic patients showing IgE binding to Phl p 12. Profilins are primarily minor allergens and are known for a high likelihood of co-sensitization as well as cross-reactivity situations caused by their sequence and structure similarity. The crystal structure of Phl p 12.0101 was determined and it revealed that this allergen may form an unusual dimer not previously observed among any profilins. For example, the Phl p 12 dimer has a completely different geometry and interface when compared with the latex profilin (Hev b 8) dimer that has its crystal structure determined. The structure of Phl p 12.0101 is described in the context of allergenic sensitization and allergy diagnostics. Moreover, the structure of the Phl p 12.0101 dimer is discussed, taking into account the production of recombinant allergens and their storage.

Are Fungal Spores Relevant Outdoor Allergens?

Alternaria alternata spores are important allergens causing "hayfever". Outdoor fungal exposure is primarily associated with increased asthma symptoms and increased risk of asthma exacerbations. In our outpatient-clinic, we investigated patients who presented with symptoms of allergic conjunctivitis and respiratory symptoms in the summertime. We found a sensitisation to Alternaria alternata in about 6 % of the investigated patients. Especially in children and teenagers, the sensitisation is clinically important. The spores of Alternaria alternata are responsible for the development and persistence of nonspecific airway hyperresponsiveness and in a group of patients also for a difficult-to-treat asthma in the summer. We should always bear in mind that prolonged symptoms (after end of June) in grass pollen allergic patients might be caused by additional sensitisation to Alternaria alternata spores or mugwort pollen. In our patients, we were able to show a sensitisation to Alternaria alternata in grass pollen allergic patients rather frequently. In the summertime, high counts of Alternaria spores and pollen often appear simultaneously. Our findings show a considerable effect of Alternaria sensitisation on the asthma morbidity and exacerbations. In this article we refer to the necessity of keeping a patient diary of allergic symptoms and the importance of information from regional pollen traps about the counts of pollen and Alternaria spores. Only then we will be able to differentiate, which allergen is responsible for the severe "hay fever", especially in patients with severe asthma episodes. Before the start of a specific immunotherapy with Alternaria alternata it is recommended to perform a mucosal provocation test, to prove the clinical significance of the sensitisation. It has been shown that also in Germany, there are high counts of Alternaria spores in the summer. The results of the pollen and alternaria count in the year 2009, measured in the regional pollen trap (Treuenbrietzen), are shown in Abb. 1, 2, 3, 4, 5. We have also found broken Alternaria spores. They are associated with increased asthma exacerbations and appear often during thunderstorms and harvesting. An allergen-specific immunotherapy with Alternaria alternata is a safe treatment and it is effective in improving respiratory function. The safety and efficacy is comparable to the one found in the allergen-specific immunotherapy with pollen.

A novel formulation of budesonide nasal spray (Budesolv 10) potentiates clinical performance in grass pollen allergic patients

Abstract Objective Purpose of this DBPC study was to evaluate onset of action and non-inferiority of a novel low dose aqueous solution of Budesonide (“Budesolv 10μg”) to Rhinocort® aqua 64μg (RA) in adult grass pollen allergic patients. Methods Budesonide, a poorly water-soluble corticosteroid, currently marketed as suspension, was reformulated to enhance solubility and local concentration on the target mucosa. Subjects received Budesolv, the market comparator RA and placebo once daily for 8 days. Allergic symptoms were induced by 6h grass pollen challenges in the Vienna Challenge Chamber at days 1 and 8 of each treatment period. First dose was applied after 1:45h to evaluate onset of action of either treatment. Nasal, ocular, asthma symptoms and objective measures of nasal secretion and nasal obstruction were evaluated. A 95% confidence interval (CI) was calculated for difference in means between active treatments. Non-inferiority was stated if the upper limit of the CI did not exceed 115% of the reference. Onset of action was defined as first time point when the difference in nasal symptoms change from baseline between active treatment and placebo was p&amp;lt;0.05. Results 75 patients concluded the study per protocol. The primary endpoint (TNSS; sum of obstruction, itch, sneeze and rhinorrhoea) was met proving non-inferiority of Budesolv compared to RA. A significant difference between Budesolv and placebo was shown for TNSS 2.45 h and for total asthma score 2 h after first dose. On day 8 Budesolv 10μg was significantly better than placebo for all parameters evaluated. Conclusion Non-inferiority of Budesolv compared to Rhinocort® was shown on day 8 of treatment. Early onset of action within 3h after first dose was evident for Budesolv only.

Two grass pollen tablets commercially available for allergy immunotherapy display different IgE epitope repertoires

BackgroundThe distribution of Pooideae species varies across Europe. Especially, Timothy is less represented in Southern than in Northern Europe. Since allergenic cross-reactivity between pollens from different grasses is only partial, grass pollen-allergic patients are expected to display different sensitization profiles, with specific IgE directed against different combinations of allergenic epitopes, depending on their living places in Europe and the grasses they are exposed to. In this context, this study aimed at comparing two tablets commercially available for allergy immunotherapy, namely a 5-grass (Cocksfoot, Meadow-grass, Rye-grass, Sweet vernal-grass and Timothy) and a 1-grass (Timothy) pollen tablets, for their ability to represent the sensitization profiles of patients, depending on whether they live in Southern or Northern Europe.MethodsSera were collected from adult patients living in Spain (n = 19) and Sweden (n = 22). Tablets were compared for their ability to inhibit the binding of patient serum IgE to pollen allergens from twelve grasses commonly distributed throughout Europe, as determined by the areas under the curves obtained by ELISA-inhibition. Tablets were adjusted to an equivalent allergenic activity, based on the CBER/FDA bioequivalent allergy unit.ResultsInhibition of the IgE binding to pollen allergens from twelve grasses was significantly stronger with the 5-grass than with the 1-grass pollen tablet (p < 0.0001), regardless of whether patients were considered as a whole or by geographical area. This difference between tablets was significantly greater for Southern than Northern European patients (p < 0.05).ConclusionsCompared to the 1-grass tablet, the 5-grass tablet generally covers better the sensitization profiles of European patients, especially patients from Southern Europe, in principle less exposed to pollen from Timothy than from other grasses. The 5-grass tablet is therefore expected to elicit larger spectra of blocking antibodies, which might have implications in light of the generally accepted mechanisms of allergy immunotherapy.

Early IL-10 producing B-cells and coinciding Th/Tr17 shifts during three year grass-pollen AIT

Abstract Background Allergen-specific immunotherapy (AIT) is a causative treatment in allergic airway disease, comprising long-term allergen administration and requiring three years of treatment. Mechanisms and biomarkers that translate into clinical efficacy remain urgently needed. Methods In an exploratory observational allergy cohort we phenotyped 32 grass-pollen allergic patients with hayfever undergoing AIT for over three years and controls using local and systemic samples for ex vivo FACS, nasal transcriptomes and in vitro phleum-stimulation at critical time windows six hours after therapeutic allergen administration and during peak-season responses. Findings The up-dosing phase is marked by increased IL-10+ B-cells with allergen-specific PD-L1 up-regulation, while effector Th1/Th17 cells and CCR6+IL-17+FoxP3+T-cells decrease. The conversion phase exhibits Th17 recovery in the absence of Th2 cells. The tolerance-mounting phase after three years of treatment is characterized by induction of Tregs while Th2 and phleum-specific Th17 responses decrease. Notably, high ratios of circulating Breg/Th17 following initial AIT correlate significantly with clinical improvement after three years. Interpretation Our exploratory data hypothezise differential shifts in the hierarchy of tolerance in three distinct phases of AIT characterized by conversion of regulatory against pro-inflammatory mechanisms, of which the Breg/Th17 ratio after initial treatment emerges as potential early prediction of AIT efficacy. Fund This study was partially funded by Allergopharma GmbH & Co. KG, intramural funding and the German Center for Lung Research (DZL).

Grass-Allergic Children Frequently Show Asymptomatic Low-Level IgE Co-Sensitization and Cross-Reactivity to Wheat

Background: Specific immunoglobulin E (IgE) sensitization to wheat is more common than a doctor’s confirmed wheat allergy and is also frequently observed in grass pollen-allergic patients (pollinosis patients). Thus, the objective of this study was to investigate the level and feature of serological IgE cross-reactivity between grass pollen and wheat in a cohort of pollinosis subjects with no diagnosis of wheat allergy. Methods: Seventy-two children, aged 5–17 years, with a doctor’s diagnosis of pollinosis, IgE towards grass pollen, and currently eating wheat were recruited. Serum samples were analyzed for IgE against wheat, timothy grass/wheat-specific allergen components, Pru p 3, and cross-reactive carbohydrate determinants (CCD) and specific IgE-binding inhibition experiments were performed. Results: Sixty percent of the grass pollen subjects were sensitized to wheat with a median of 0.5 kU_A/L. Wheat-sensitized subjects were more often sensitized to the two allergens, Phl p 12 and CCD, known to be cross-reactive between grass and wheat. Sensitizations to seven wheat-specific allergens derived from the gluten fraction were, with the exception of one individual, only found in wheat-sensitized subjects. These subjects also more often reported current and past history of allergy to staple foods (milk, egg, wheat, soy, and fish). Conclusion: Wheat sensitization caused by cross-reactivity but also by sensitization to wheat-specific allergens was common in the grass-allergic children and also associated with allergy to staple foods other than wheat. The results indicate the presence of a subgroup of pollinosis patients with simultaneous sensitization to wheat and food allergy not only caused by cross-reactions.

Lolium perenne peptide immunotherapy is well tolerated and elicits a protective B-cell response in seasonal allergic rhinitis patients.

BackgroundSystemic allergic reactions are a risk for allergen immunotherapy that utilizes intact allergen preparations. We evaluated the safety, efficacy and immune mechanisms of short‐course treatment with adjuvant‐free Lolium perenne peptides (LPP) following a 6‐week dose‐escalation protocol.MethodsIn a prospective, dose‐escalation study, 61 grass pollen–allergic patients received 2 subcutaneous injections of LPP once weekly for 6 weeks. Safety was assessed evaluating local reactions, systemic reactions and adverse events. The clinical effect of LPP was determined by reactivity to the conjunctival provocation test (CPT). Specific IgE, IgG4 and blocking antibodies were measured at baseline (V1), during (V6) and after treatment (V8).ResultsNo fatality, serious adverse event or epinephrine use was reported. Mean wheal diameters after injections were <0.6 cm and mean redness diameters <2.5 cm, independent of dose. Transient and mostly mild adverse events were reported in 33 patients. Two patients experienced a grade I and 4 patients a grade II reaction (AWMF classification). At V8, 69.8% of patients became nonreactive to CPT. sIgG4 levels were higher at V6 (8.1‐fold, P < .001) and V8 (12.2‐fold, P < .001) than at V1. The sIgE:sIgG4 ratio decreased at V6 (−54.6%, P < .001) and V8 (−71.6%, P < .001) compared to V1. The absolute decrease in IgE‐facilitated allergen binding was 18% (P < .001) at V6 and 25% (P < .001) at V8.ConclusionIncreasing doses of subcutaneous LPP appeared safe, substantially diminished reactivity to CPT and induced blocking antibodies as early as 4 weeks after treatment initiation. The benefit/risk balance of LPP immunotherapy remains to be further evaluated in large studies.

Clinical Efficacy of a Recombinant Grass Pollen Vaccine One Year after a 4 Month Treatment Course

Immediate and sustained clinical efficacy of a recombinant grass pollen vaccine (BM32) consisting of IgE epitope peptides of Phl p 1, 2, 5 and 6 was evaluated in terms of optimized treatment schedule of a 4 month pre- seasonal treatment in grass pollen allergic patients (NCT02643641). Four treatment schedules (3, 4, 5 times active vs. Placebo) of BM32 were evaluated during grass pollen seasons 2016 and 2017. Symptom Scores (SS), Medication Scores (MS) and Combined Scores (SMS) of actively treated subjects were compared to placebo. In 2016 scores were correlated with symptoms (TNSS) in the challenge chamber. Symptoms and medication intake were reported daily during entire grass pollen season. SS was reported on a four point scale comprising 4 nasal symptoms (runny nose, blocked nose, sneezing, itchy nose) and 2 ocular symptoms (itchy/red eyes, and watery eyes). It was calculated as the sum of scores divided by 6. In the MS score values were assigned to categories of medication and calculated as predefined in the protocol. 124 subjects were included in the full analysis set. The mean daily SMS during the pollen peak immediately after treatment with 3, 4 or 5 injections of BM32 improved by 15%, 3% and 25 % vs. Placebo. During the grass pollen peak 2017 no further treatment effect could be demonstrated. Correlation coefficient of TNSS in the challenge chamber and SS during season 2016 was .5. Five active injections demonstrated the best immediate clinical efficacy, but no sustained effect. BM32 was safe and well tolerated.

Beta-Expansin of Bermuda, Johnson, and Para grass pollens, is a major cross-reactive allergen for Allergic Rhinitis patients in subtropical climate.

Subtropical grass pollens of Bermuda (BGP), Johnson (JGP), and Para or buffalo grass (PGP), are common causes of pollen allergies in warm climate area. Allergic rhinitis (AR) patients had positive skin prick test (SPT) to extract of these 3 grass pollens. However, no allergenic proteins of 3 grass pollens have never been studied. To identify major allergens of BGP, JGP, and PGP in Thai grass pollen-allergic patients and to examine their sIgE cross-reactivity. Serum of nine AR patients with positive SPT to at least 2 of 3 studied pollens were collected. Based on availability, only ImmunoCAP of BGP and JGP were available to determine a level of sIgE. Profiles of sIgE bound proteins from BGP, JGP, and PGP, were obtained by immunoblot. Major IgE bound protein was identified by liquid chromatography-tandem mass spectrophotometry (LC-MS/MS). Cross-reactivity of purified major allergen of the 3 grass pollens was determined by inhibition of sIgE in both ELISA and immunoblot. AR patients who have positive SPT to extract of BGP, JGP, and PGP, were 9, 8, and 6, respectively. Positive sIgE (> 0.35 kUA/L) to BGP and JGP were found in 9 and 8 patients, respectively. Eight profiles of IgE bound proteins of the 3 grass pollens showed 29-30 kDa pollen protein as major allergen and was identified as beta-expansin (ExpB). Moreover, purified ExpB of the 3 grass pollens cross-inhibited serum sIgE. ~30 kDa ExpB of BGP, JGP, and PGP, is major cross-reactive allergen for AR Thai patients.

RCAT reflects symptom control and quality of life in allergic rhinoconjunctivitis patients.

The Global Allergy and Asthma European Network (GA2 LEN) Taskforce has requested more data on correlations between various patient-reported outcomes (PROs) in clinical trials on allergy. We compared three tools-the Rhinitis Control Assessment Test (RCAT), Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) and Rhinitis Total Symptom Score (RTSS)-to determine whether the RCAT alone is a sufficient primary outcome parameter in clinical trials on allergic rhinoconjunctivitis. In two double-blind, placebo-controlled immunotherapy studies, 33 patients allergic to grass pollen and 94 to birch pollen completed two questionnaires (RCAT and RQLQ) and kept their own symptom diary from which the RTSS was calculated. Upon comparing RCAT and RQLQ results, we found strong correlations of r = -0.871 for grass pollen-allergic patients and r = -0.795 for birch pollen-allergic patients. The comparison between RCAT and RTSS results showed a strong correlation of r = -0.811 (grass pollen-allergic patients) and a moderate correlation of r = -0.539 (birch pollen-allergic patients). In the RCAT, 69.7% of grass pollen-allergic patients and 45.7% of birch pollen-allergic patients receiving guideline-concordant therapy were regarded as having insufficiently controlled symptoms. The strong correlations suggest that the RCAT alone is equivalent to the RQLQ with respect to patients' symptom control and quality of life. Patients with uncontrolled symptoms can be identified using the RCAT. Hence, the physician can decide whether symptomatic therapy can be intensified or allergy immunotherapy should be administered.

Is a positive intracutaneous test induced by penicillin mediated by histamine? A cutaneous microdialysis study in penicillin-allergic patients

BackgroundDiagnostic workup of penicillin allergy comprises skin testing with penicillins, and patients are deemed allergic if skin test is positive. However, the literature suggests that skin test-positive patients may be challenge-negative, indicating that the skin test may be falsely positive.ObjectiveTo investigate real-time histamine release from a positive intracutaneous test induced by penicillin in patients with positive and negative challenges to penicillin.MethodsSkin microdialysis was performed in 21 penicillin-allergic patients with positive skin test, 13 non-allergic volunteers serving as negative controls, and 7 grass pollen-allergic patients serving as positive controls. Histamine was measured by microdialysis after skin test with penicillin/grass/NaCl. Penicillin challenge was subsequently performed in 12 of the patients.ResultsOnly 10/21 patients (47.6%) were skin test positive at microdialysis. During microdialysis 13 single intracutaneous tests were positive and histamine was detected in 4/13 occurring in four challenge positive patients. Thirteen/21 patients (61.9%) were deemed allergic to penicillin; eight had positive skin test. Two patients with positive skin test were challenge negative. In grass pollen allergic patients, 7/7 had a positive intracutaneous test to grass and all released histamine in the wheals. All 13 negative controls had negative intracutaneous test to penicillin and no histamine release.ConclusionHistamine was only detected in the minority of positive intracutaneous tests with penicillin in penicillin-allergic patients. Other mediators may be involved.