To the Editor, Immediate hypersensitivity reactions are related to mast cell and/or basophil activation. The mediators released such as tryptase and histamine are involved in clinical symptoms and are key parameters that contribute to diagnosis. Serum tryptase concentrations peak between 30 minutes and 4 hours following the reaction. Tryptase release is considered a robust marker of mast cell degranulation but is not informative in mild reactions.1 Histamine is released at the early beginning of the reaction but has a short half-life. The concentration value can be altered by pre-analytic conditions.2 Anaphylactic reactions can occur during night and week-end when laboratories can’t take charge of samples. To our knowledge, no thorough study of the stability in whole blood of these markers in anaphylaxis has been published. The aim of our study was to evaluate the impact of whole blood sample storage conditions (temperature and delay before centrifugation and plasma collection) on the reliability of tryptase and histamine measurements.Blood samples from 14 patients suspected of anaphylactic reactions (grade 2 to 4 of the Ring and Messmer scale)3 and from 10 volunteers were collected on EDTA after signed informed consent (CCPPRB Caen Basse-Normandie protocol 2004-32). The description of the patient anaphylactic episodes appears in Table 1.When received in the lab, an aliquot of whole blood was processed for diagnostic (reference measurement) and the remaining was divided in aliquots stored at room temperature (RT) or at +4°C for 24, 72 hours or 7 days (patients) or 2, 6, 24 or 72 hours for controls before centrifugation and plasma collection.Total tryptase concentrations were measured by an automated fluoroimmunoassay (ThermoFisher, Phadia SAS, ). Increased tryptase is defined as ≥ 1.2 x basal value + 2 µg.L-1.4 In our hands, tryptase uncertainties of measurement for low and high concentrations (9 µg.L-1 and 38.2 µg.L-1) are 17% and 16% respectively, in accordance with published results.5 Plasma histamine concentrations were measured by a radioimmunoassay (Beckman Coulter, Immunotech, France). Increased values defined by the manufacturer are >10 nmol.L-1, in accordance with published data.6 In our hands, histamine uncertainties of measurement for low and moderate concentrations (4.7 nmol.L-1 and 12.9 nmol.L-1) were 22% and 25%, respectively.The differences between the concentrations measured before and after storage were compared by paired two-tailed t-tests using SAS software. Results were considered significant for p < 0.05.As shown in Figure 1A, storage conditions did not modify tryptase concentrations (linear regression: slope=1.079, R²=0.9675). Tryptase concentrations appeared stable in whole blood left at +4°C for 7 days or 72 hours at RT.Histamine concentrations in patient samples were not modified during 72h at +4°C (Figure 1B) or at RT (Figure 1C). In the control group at RT, histamine concentrations were significantly increased at 6 hours (p=0.005) although moderately increased and staying within the limits of uncertainty measurement and never reaching the positivity threshold (Figure 1E). After 24 hours at RT a false positivity was observed for 8 of 10 samples (p<0.0001) (Figure 1E). At +4°C, histamine concentrations were significantly increased after 24 hours (p<0.0001) but remained in the limits of uncertainty measurement and under the threshold of positivity (Figure 1D). After 72h at +4°C, histamine concentrations exceeded the limits of uncertainty measurement and the positivity threshold for 4 samples of 10 (Figure 1D).Tryptase and histamine measurements are recommended to prove degranulation in anaphylaxis.7 Anaphylactic reactions occur unexpectedly. It is thus important to master sample shipment and processing before mediator measurement.The knowledge of possible artifacts modifying the measured values is necessary for the biochemist to address accreditation criteria of pre-analytic requirements (ISO 15189 standard) and for the physician to rely on trustable diagnostic data.Tryptase stability in whole blood had not been described. Our data has shown no impact on results after 72h at RT or 7 days at +4°C. Tryptase stability in plasma or serum has been evaluated by the manufacturer who ensured stability for 48h at RT or 5 days at +2°C to +8°C (Thermofisher).8 Thus, measured values of tryptase appear highly reliable.Histamine stability in whole blood had only been evaluated in controls and false positive results may be attributed to passive release from basophil during prolonged storage.2 We observed no impact for patient blood samples after 72h at +4°C or at RT. In contrast, false positive results were observed in controls after storage at RT during 24h or at +4°C during 72h. Histamine is known to be stable in the plasma obtained after centrifugation up to 4 days at RT for patients and controls.9According to these results, we suggest that whole blood samples can be stored at +4°C up to 72h for histamine and 7 days for tryptase when the laboratory is not available immediately. In any case, the biochemist must accept all these unrenewable samples. It is his role to take into account the pre-analytical conditions to interpret the results and provide helpful information to the physician.Keywords : pre-analytic; tryptase; histamine; whole blood.
Background The prevalence of allergy to cat is expanding worldwide. Allergen-specific immunotherapy (AIT) has advantages over symptomatic pharmacotherapy and promises long lasting disease control in allergic patients. However, there is still a need to improve cat AIT regarding efficacy, safety and adherence to the treatment. Here we aim to boost immune tolerance to the major cat allergen Fel d 1 by increasing the anti-inflammatory activity of AIT with the established immunomodulatory adjuvant CpG, but at a higher dose than previously used in AIT. Methods Together with CpG, we used endotoxin-free Fel d 1 as therapeutic allergen throughout the study in a BALB/c model of allergy to Fel d 1, thus mimicking the conditions of human AIT trials. Multidimensional immune phenotyping including mass cytometry was applied to analyze AIT-specific immune signatures. Results We show that AIT with high-dose CpG in combination with endotoxin-free Fel d 1 reverts all major hallmarks of allergy. High dimensional CyTOF analysis of the immune cell signatures initiating and sustaining the AIT effect indicates the simultaneous engagement of both, the pDC-Treg and -B cell axis, with the emergence of a systemic GATA3+ FoxP3hi biTreg population. The regulatory immune signature also suggests the involvement of the anti-inflammatory TNF/TNFR2 signaling cascade in NK and B cells at an early stage and in Tregs later during AIT. Conclusion Our results highlight the potential of CpG adjuvant in a novel formulation to be further exploited for inducing allergen-specific tolerance in patients with cat allergy or other allergic diseases in the future.
To the Editor.The beneficial effects of Allergen Specific Immunotherapy (AIT) relies on the induction of allergen-specific Regulatory T-cells (Tregs) (1). Tregs, a subpopulation of CD4+CD25+T-cells expressing the specific transcription factor Foxp3, are not functionally homogeneous and their detection is complex and uncertain due to FoxP3 intracellular localization. Furthermore, FoxP3+ Tregs might become unstable and halt the production of their functional suppressive cytokines in inflammatory conditions (2) (1). In its place, the surface antigen CD127, whose expression inversely correlates with FoxP3, conveniently identifies Tregs as CD4+CD25+CD127negcells (3) (2), so surmounting the problems of FoxP3 stability and intracellular detection. Tregs also constitutively express the inhibitory antigen CD39, enhanced in highly suppressive memory Tregs (4) (3). Furthermore, HLA-DR expression is a monitor of Treg differentiation status and identifies a functionally and greatly suppressive population (1,5) (1,5). Lack of CD45RA characterizes memory T cells enabled to survive for long periods, even in absence of specific antigen, showing increased activity upon re-exposure and able to induce apoptosis in target cells (6) (3). CD4+CD25highCD39+CD127negcells are subtyped as Resting (CD45RA+/HLA-DRneg: rTreg), Activated (CD45RAnegHLA-DRneg: aTreg) and Effector (CD45RAnegHLA-DRlow/high: eTreg) Tregs (6) (6). This latter subtype includes terminally differentiated Tregs, the most highly suppressive (5) (7) (Supplementary Figure 1). They are different from secreting or type III Tregs expressing CD127 that represent a short-lived terminally differentiated population (5,6,8) . In order verify possible correlations between specific subsets of Treg and the effectiveness of AIT, we applied this analytical approach to study Treg profile in adolescents suffering from mite allergic rhinitis, pre and 12 months post Sublingual Immunotherapy (SLIT) with mite monomeric allergoid, an acid-resistant allergen known to elicit early T reg-activation (7,8). The study was approved by the Ethical Committee of University “G. d’Annunzio”, Chieti-Pescara. All patients and parents signed a written informed consent after having been informed about the procedures of the study.Twenty patients diagnosed with mite-allergic persistent rhinitis with or without asthma were enrolled. Allergic rhinitis (AR) was graded according to ARIA guidelines in 1) intermittent mild, 2) intermittent moderate/severe, 3) persistent mild and 4) persistent moderate/severe. At the enrollment, each patient marked in a 100 mm visual analogic scale (VAS) the level of its health status related to allergy with 0 the best status and 100 the worst.All patients were treated by SLIT with mite monomeric allergoid (LAIS - Lofarma, Milan, Italy) at 1000 UA four times/week every other day, for 12-months. No adverse local and systemic reactions were detected. The effectiveness of SLIT was established comparing VAS, ARIA grading and ACT questionnaire performed after 12-months of treatment with their basal values. Two blood samples were drawn pre/post SLIT to be analyzed for Regulatory T-cells. Clinical and demographic details of the studied population, analytical methods, statistical approach and the outline of the study are detailed in the online supplementary material .Rhinitis scores VAS and ARIA significantly decreased after SLIT (Table 1), with the same statistical significance (Wilcoxon z -3.7236; p = 0.0002). Improvement was evidenced also in the subgroup of asthmatic patients (n=7) since ACT scores significantly increased from the baseline value of 18 (16-19) up to 24 (20-25) after 12 months of treatment (the low number of patients does not allow application of efficient statistics).Tregs were analyzed as frequency of total Treg cells and their three subsets, namely Resting (rTregs), Activated (aTregs) and Effector (eTregs), within the parental population of CD4+cells. Total Tregs did not change significantly; rTreg significantly decreased (Wilcoxon z-3.6214, p<0.0003), while, the abundance of aTregs and eTregs significantly incremented (Wilcoxon z-2.9011, p<0.05 and z-3.077, p=0.002, respectively) (Table 1). A significant negative correlation has been observed between the decrease in rTreg and the increase in aTreg (Spearman’s ρ-0.69391, p<0.02) and increase in eTreg cells (Spearman’s ρ-0.56845, p<0.02) (Figure 3 in supplementary material).HLA-DR resulted significantly up-regulated in all Tregs from 4.93±3.1 to 6.92±5.1 MFI (Wilcoxon z-4.2026, p <0.00001). HLA-DR increased on aTregs from 3.4±3.03 to 4.91±3.2 MFI (Wilcoxon z-3.2479, p=0.001) and on eTregs from 1.54±0.66 to 2.0±1.45 MFI (Wilcoxon z-2.9664, p=0.005). CD39 was found differently expressed in the three subsets of Tregs at baseline, with Resting<Activated<Effector. After 12 months of SLIT, CD39 surface expression was found significantly increased in all Tregs from 6.9±4 to 8.02±5 MFI (Wilcoxon z-3.1049, p=0.001) (HLA-DR and CD39 changes are reported in Table 1). We found some interesting correlations between laboratory data and clinical parameters. Changes in eTregs significantly correlated with both ARIA (Spearman’s ρ=0.58728, p=0.013) (Figure 1A) and VAS (Spearman’s ρ=0.49172, p=0.044) (Figure 1B) variations after SLIT. While a significant negative correlation was found between rTregs and clinical parameter changes after treatment (Spearman’s ρ-0.48482, p=0.0491). Changes in HLA-DR expression on all Treg cells significantly correlated with variation in VAS pre-/post-SLIT (Spearman’s ρ=0.54104, p= 0.01376) (Figure 1C). No other correlations were found except for the lowest increase (< 8%) of memory Tregs (CD45RAneg) detected in patients with the lowest levels of mite-specific serum IgE (not shown).To our knowledge this is the first report on successful SLIT being associated with re-patterning of the differentiation status of Tregs, with high rates of the most suppressive Treg subtypes: activated and effector, characterized by higher expression of HLA-DR and CD39 both playing inhibitory function in Tregs. Moreover, effective SLIT seems to be associated with the generation of cells lacking CD45RA that characterizes memory T cells with increased activity upon re-exposure to the antigen. Our results suggest that SLIT also induced empowerment of Treg inhibitory function, likely compensating the under-representation of Tregs observed in allergic patients (9) (9). In AR children, there are evidences that Tregs have defect in suppressing IgE production and that they can be incremented by mite SLIT.Next step of our study will be to evidence if such relationship between effective SLIT and Treg re-patterning is present in the first months of SLIT, with a view to profiling Tregs for the early identification of SLIT responders/non-responders by mean of a straightforward and non-invasive blood test.
Immediate and non-immediate hypersensitivity reactions to iodinated contrast media (ICM) have been reported to occur in a frequency of about 0.5-3% of patients receiving non-ionic ICM. The diagnosis and management of these patients is controversial among guidelines published by various national and international scientific societies, with recommendations ranging from avoidance or premedication to drug provocation test. This position paper aims to give recommendations for the management of patients with ICM hypersensitivity reactions and analyze controversies in this area. Skin tests are recommended as the initial step for diagnosing patients with immediate and non-immediate hypersensitivity reactions; besides, they may also help guide on tolerability of alternatives. Drug provocation test is the gold-standard; although, as it is a risky procedure, the decision for performing it needs to be taken based on a risk-benefit analysis. Another source of controversy is the role of in vitro tests for diagnosis and pretreatment for preventing reactions.
Modern healthcare requires a proactive and individualized response to diseases, combining precision diagnosis and personalized treatment. Accordingly, the approach to patients with allergic diseases encompasses novel developments in the area of personalized medicine, disease phenotyping and endotyping and the development and application of reliable biomarkers. A detailed clinical history and physical examination followed by the detection of IgE immunoreactivity against specific allergens still represents the state of the art. However, nowadays, further emphasis focuses on the optimization of diagnostic and therapeutic standards and a large number of studies have been investigating the biomarkers of allergic diseases, including asthma, atopic dermatitis, allergic rhinitis, food allergy, urticaria and anaphylaxis. Various biomarkers have been developed by omics technologies, some of which lead to a better classification of the distinct phenotypes or endotypes. The introduction of biologicals to clinical practice increases the need for biomarkers for patient selection, prediction of outcomes and monitoring, to allow for an adequate choice of the duration of these costly and long-lasting therapies. Escalating healthcare costs together with questions on the efficacy of the current management of allergic diseases requires further development of a biomarker-driven approach. Here, we review biomarkers in diagnosis and treatment of asthma, atopic dermatitis, allergic rhinitis, viral infections, chronic rhinosinusitis, food allergy, drug hypersensitivity and allergen-immunotherapy with a special emphasis on specific IgE, microbiome and epithelial barrier. In addition, EAACI guidelines on biologicals are discussed within the perspective of biomarkers.
Background: There is limited information on risk factors for eczema in adults. Recent evidence suggests that air pollution may be associated with increased incidence of eczema in adults. We aimed to assess this possible association. Methods: Ambient air pollution exposures (distance from a major road, nitrogen dioxide [NO2], fine particulate matter with an aerodynamic diameter ≤2.5 µm [PM2.5]) were assessed for the residential address of Tasmanian Longitudinal Health Study participants at ages 43 and 53 years. Eczema incidence (onset after age 43 years), prevalence (at 53 years) and persistence were assessed from surveys, while sensitisation was assessed using skin prick tests. The presence or absence of eczema and sensitisation was classified into four groups: no atopy or eczema, atopy alone, non-atopic eczema, and atopic eczema. Adjusted logistic and multinomial regression models were fitted to estimate associations between ambient air pollution and eczema, and interaction by sex was assessed. Results: Of 3153 participants in both follow ups, 2369 had valid skin prick tests. For males, a 2.3 ppb increase in baseline NO2 was associated with increased risk of prevalent eczema (OR=1.15 [95%CI 0.98-1.36]), both non-atopic (OR=1.39 [1.02-1.90]) and atopic eczema (OR=1.26 [1.00-1.59]). These associations were not seen in females (P for interaction=0.08, <0.01). For both sexes, a 1.6 µg/m3 increase in PM2.5 exposure at follow-up was associated with increased odds of aeroallergen sensitisation (OR=1.15 [1.03-1.30]). Conclusion: Increased exposure to residential ambient air pollutants was associated with an increased risk of eczema, only in males, and aeroallergen sensitisation in both genders.
EDITORIAL The average global temperatures on our planet are increasing due to rising anthropogenic greenhouse gases in the atmosphere, in particular carbon dioxide (CO2).1,2 There is an urgent need to call for action on global warming, which is resulting in extreme weather and related catastrophes.1 ,2 The Earth’s rising temperature is evidenced by warming of the oceans, melting glaciers, rising sea levels, and the diminished snow cover in the Northern Hemisphere. Climate-related factors can affect interactive atmospheric components (chemical and biological) and their interrelationship with human health.Climate change, a physics and meteorological event that affects health in the whole biosphere started to receive attention around the mid-twentieth century. Air pollution is the driving force of the Earth’s warming powered by the greenhouse effect (Figure 1). Environmental changes are occurring in frequency, intensity, type of precipitation, and extreme weather events, such as heatwaves, droughts, floods, blizzards, thunderstorms, sandstorms, and hurricanes. These are real and daunting challenges for the human and biosphere health, impacting the food and water supplies.1 ,2 Urbanization, with its high level of vehicle emissions and westernized lifestyle, is linked to the rising levels of particulate matter in the air, food supplies, soil, freshwater, and oceans. These environmental changes are correlated with the increased frequency of respiratory allergic diseases and bronchial asthma observed over recent decades in most industrialized countries and is continuously rising in developing countries.1-5This issue of Allergy focuses on the interrelationship between climate change, air pollution and human health.3-7Climate change is an important medical aspect in allergology as we are observing an increasing incidence of allergic diseases indirectly related to rising temperatures and are becoming a high socio-economic burden.1-3,8 Allergies and asthma appear to be at the front line of the sequelae of climate change along with infectious and cardiovascular diseases.1,5Cecchi et al. focus on the development and exacerbation of allergic diseases can be explained in terms of the exposome, a concept that includes all the environmental exposures from conception onwards. Multiple factors can trigger a pollen-induced respiratory allergy, such as airborne endotoxin levels and microbial composition of pollen, and these comprise a “pollen exposome”.4,9Susan Prescott has written an editorial in this issue bringing the attention to climate change and bidiversity aspects. At the time of Neil Armstrong’s lunar landing 50 years ago, Prof. Rene Dubos, a renowned microbiologist, delivered the seminal lecture “The Spaceship Earth”. He was ahead of his time and warned of an “altered immunity” driven by environmental problems and loss of biodiversity. Most of his predictions proved correct and we are now understanding at a molecular level the pathophysiological mechanisms involved in allergic diseases.8Climate change indirectly affects allergies by altering the pollen concentrations, allergenic potential, composition, migration of species and growth of new ones. Air pollution and climate change have resulted in the faster growth of allergenic plants, increasing the aeroallergen load for patients with inhalant allergy. Phenological studies indicate longer pollen seasons and emerge earlier in the year.1,4,5,8 Pollen and mold allergies are generally used to evaluate the interrelationship between air pollution and allergic respiratory diseases, such as rhinitis and asthma. Studies show that plants exhibit enhanced photosynthesis and reproductive effects and produce more pollen as a response to high atmospheric levels of CO2. 1,4,8 Pollen allergens have been demonstrated to trigger the release of pro-inflammatory and immunomodulatory mediators that accelerate the onset of allergy and the IgE-mediated sensitization. Lightning storms or wet conditions rupture the pollen grains releasing the allergenic proteins that cause asthma exacerbations in patients with pollinosis (thunderstorm-asthma).1,3,4,7,10 As a result of climate change, patients with seasonal allergic rhinoconjunctivitis and asthma have more intense symptoms and need stronger medication.1,4,8 In addition to respiratory illnesses, Fairweather et al. demonstrate the effect of environmental changes on cardiovascular, brain and mind, gastrointestinal, skin, immunologic and metabolic effects.1,3,4,7 The migration of stinging and biting insects to cooler climates has caused an increase in insect allergies in those areas.Prunicki et al. focus on the contribution of wildfires and deforestation and their contribution to global warming and immunological effects. It should be noted that in the last fifty years, half of the pluvial forests on Earth have been lost. Deforestation and forestation degradation is estimated to occur at a rate of 13 million hectares per year, mostly for agricultural purposes. Wildfires are becoming increasingly frequent, posing a serious risk to human health. The fine particulate matter (PM2.5) in wildfire smoke exacerbates asthma attacks, among other health problems. A study of 67 subjects demonstrated that those exposed to wildfire smoke had significantly higher levels of C-reactive protein and IL-1β compared with controls.6 The elevated levels of these two biomarkers are indicative of airway inflammation.Global warming and climate change need actions throughout the whole world with joined forces of all capabilities. These efforts are sometimes hampered by the unresponsiveness of governmental institutions and the general population, the lack of infrastructure and poverty. An action plan is needed to disseminate information on health-related problems associated with climate change. Patients with pollen allergies or asthma should be educated on the higher health risk during a thunderstorm or pollen season and the need for appropriate medication if staying outdoors. In collaboration with environmental organizations, physicians should take the lead to promote actions to mitigate air pollution and advocate the need to reduce global warming to protect our health.
EDITORIAL Coronavirus disease‐19 (COVID‐19) is a new disease caused by SARS‐CoV2. Since the beginning of 2020, it has become one of the main challenges of our times, causing a high incidence of severe pneumonia, acute respiratory distress syndrome (ARDS), multiorgan failure and death1. At the root of COVID-19 lies the sudden development of ‘cytokine storms’, hyper-inflammatory responses involving the release of pro-inflammatory cytokines (e.g., TNF-α, IL-6, IL-1, IL-8, and MCP-1) that impair the gas exchange function of the lung and lead in select patients, mostly with underlying comorbidities, to multiorgan failure and death1,2. Additional complications triggered by ‘cytokine storms’ include endothelial dysfunction and hypercoagulation, increasing the risk of thromboembolytic events, and life-threatening cardiovascular complications. Anti-inflammatory therapies are thus being considered for alleviating the damaging side effects of hyper-inflammation with many trials including anti-cytokine biologicals, disease-modifying antirheumatic drugs (DMARDs) and corticosteroids being ongoing3. Surprisingly, among them dexamethasone has taken center stage as initial results from the RECOVERY trial, a large multicenter randomized open-label trial for hospitalized patients run in the United Kingdom, revealed notable efficacy in the treatment of critically ill COVID-19 patients4.Dexamethasone is one of the oldest synthetic glucocorticoid agonists synthesized in 1957 and introduced into the clinic in 1961. When administered at 6 mg daily, either orally or intravenously for 10 days, dexamethasone was shown in the RECOVERY trial to improve survival rates of hospitalized patients with severe COVID-19 receiving oxygen or being on mechanical ventilation by a remarkable 30%4. Benefit was restricted to patients requiring respiratory support whereas in milder cases this was not clear. This notable efficacy of dexamethasone treatment goes against the current view of corticosteroid use in respiratory viral infections which remains contradictory. Although corticosteroids improve ventilator weaning and can lower the intensity of the host response to the virus, tempering the ‘cytokine storm’ and limiting immunopathology, they can also reduce viral clearance and lead to more severe disease. Understanding therefore how dexamethasome mediates its effects is of paramount importance.Dexamethasone, as other corticosteroids, is held to mediate its anti-inflammatory and immunosuppressive effects via the glucocorticoid receptor. Upon ligand binding, the receptor-corticosteroid molecule complex moves into the cell nucleus, where it dimerizes and binds to glucocorticoid response elements (GRE), acting as transcriptional repressor or transactivator of diverse sets of genes. This results in the inhibition of inflammatory cell activity, including neutrophils, macrophages and lymphocytes, and the suppression of pro-inflammatory cytokines such as TNF and interleukins and other genes such as cyclooxygenase-2 and inducible nitric oxide synthase5. However, we have recently uncovered that dexamethasone can also induce the D-series proresolving lipid mediator pathway leading to the production of 17-HDHA and the protectins D1 and DX6. These are potent major players of the molecular machinery driving the resolution of inflammation, i.e. the proper regulated termination of pro-inflammatory responses involving the catabolism of pro-inflammatory mediators, the removal of inflammatory cells and the restoration of the tissue in a timely and highly coordinated manner7. Although resolution of inflammation has long been considered to occur spontaneously as a result of the waning of pro-inflammatory responses, this is now known to be an ordered and highly regulated process involving the timely production of enzymatically oxygenated lipid-derived mediators such as protectins, D-series resolvins and maresins derived from the omega-3 fatty acid docosahexaenoic acid (DHA), E-series resolvins derived from eicosapentaenoic acid (EPA), and lipoxins biosynthesized from omega-6 fatty acids following eicosanoid class switching7. Interestingly, certain lipid mediators have been shown to exert additional non-conventional functions; resolvin D4 can attenuate pathologic thrombosis, reduce NETosis and promote clot removal8 which is now recognized as a key pathology of COVID-19 infection, while resolvin E4 (RvE4) stimulates efferocytosis of senescent erythrocytes in hemorrhagic exudates especially under hypoxic conditions that characterize COVID-199. Moreover, corticosteroids have been reported to reduce fibrinogen and procoagulant factors under pro-inflammatory conditions and increase anticoagulant factors10.The ability of viral infections to induce proresolving lipids has been reported earlier. Toll-like receptor 7 (TLR7), a major pattern recognition receptor of viral RNA, activates PD1 and PDX production11. Moreover, influenza virus infection has been demonstrated to drive proresolving lipid mediator networks including the production of PD1 which limits influenza pathogenicity by directly interacting with the RNA replication machinery to inhibit viral RNA nuclear export12,13. Notably, in particularly virulent strains of influenza virus such as the H5N1 avian strain, PD1 formation is not sufficiently upregulated, leading to more efficient viral replication and host demise12. It is therefore plausible that the efficacy of dexamethasone in COVID-19 is due at least in part to its ability to induce proresolving lipid mediators that possess multiple anti-inflammatory and proresolving actions tempering down inflammation and promoting its resolution, preventing coagulation and enhancing viral and bacterial clearance (Figure 1) yet are not immunosuppressive . Whether other corticosteroids beyond dexamethasone can also mediate such effects, and to what extent, is not known. Whether inhalable corticosteroids, such as those given to asthmatic patients, can also induce proresolving lipid mediator networks locally and thus prevent the development of severe SARS‐CoV‐2 infection remains to be determined. There is evidence that asthmatic patients exhibit reduced incidence of severe and/or critical COVID-1914.Recently, COVID-19 patients showed increased association of serum arachidonate-derived proinflammatory lipid mediators, e.g. prostaglandins, in severe COVID -19 infections while some pro-resolving mediators such as resolvin E3 were up-regulated in the moderate COVID-19 group suggesting that an imbalance in lipid mediators with a swift toward pro-inflammatory mediators in severe disease may contribute to COVID-19 disease severity15. Although the involvement of proresolving lipid mediator pathways in COVID-19 is an attractive hypothesis, further evidence from human trials is needed as there are no studies at present reporting the induction or modulation of such networks in the context of the various disease stages and treatments. It is thus of uttermost priority to investigate proresolving lipid mediators in COVID-19, in a temporal and longitudinal manner, as modulating these networks either through drug treatment or direct administration of resolvin and protectins agonists has the potential to affect this highly lethal and devastating disease in a way other approaches cannot. Such studies are therefore eagerly awaited.
To the Editor, Sulforaphane [1-isothiocyanato-4-(methylsulfinyl)butane] is a clinically relevant nutraceutical compound present in cruciferous vegetables (Brassicaceae). It is used for the prevention and treatment of chronic diseases and may be involved in ageing.1Along with other natural nutrients, sulforaphane has been suggested to have a therapeutic value for the treatment of the coronavirus disease 2019 (COVID-19).2 Sulforaphane is an isothiocyanate stored in its inactive form glucoraphanin.3 The enzyme myrosinase, found in plant tissue and in the gut microbiome, is involved in the conversion of glucoraphanin to its active form sulforaphane.4
Dear Editor: I read with interest the report by Antonella et al.1 This report described a case of the acute scrotum caused by Anisakis . As the authors write, this condition is rare in its own right. However, I would like to discuss two other rare aspects of this case: that it occurred during childhood and that acute scrotal disease and anaphylaxis occurred simultaneously.There has been a long debate as to whether anaphylaxis caused by Anisakis occurs with the ingestion of live insect bodies only or with dead insect bodies as well.2 Since several allergen components of Anisakis have been identified and their tolerance to heat has been reported, it is theoretically possible that anaphylaxis could occur with the ingestion of dead larvae body parts. However, some reports suggest that even patients sensitized to Anisakis may not develop allergic symptoms with the ingestion of frozen Anisakis larvae.3Nevertheless, there have been very few cases of gastrointestinal anisakiasis and anaphylaxis occurring simultaneously. In fact, previous literature has shown that in 40 cases of anaphylaxis which occurred due to the ingestion of live fish, upper gastrointestinal endoscopy revealed no difference in phenotype between the 20 cases in which live larvae were found and the 20 cases in which they were not found, and even in the case of live Anisakis bodies, the abdominal symptoms were minor.4 Of the 128 cases included in our previous study, only one could be said to have developed anaphylaxis and gastric anisakiasis simultaneously.5The patient we experienced was a 36-year-old woman with a previous history of gastric anisakiasis. Urticaria, watery diarrhea and vomiting, and respiratory distress developed three hours after eating sashimi (sliced raw fish) of young yellowtail. The patient was rapidly administered adrenaline intramuscular injection, followed by H1/H2 blockers and methylprednisolone, and admitted to the hospital for observation. However, after a day of admission, she continued to complain of intermittent epigastric pain and underwent upper gastrointestinal endoscopy. A live Anisakis larva was found in the gastric cavity, and the epigastric pain disappeared after its removal. This case was negative for fish-specific IgE and positive forAnisakis -specific IgE (ImmunoCAP🄬 fluorescent enzyme immunoassay). Similar cases have been reported recently by Shikino et al.6The reason for such phenotypic variations after the ingestion of liveAnisakis is a direction for future research. From this perspective, it would be very interesting to explore what pathological changes, e.g., eosinophilic granulomatous changes, had occurred in the scrotum or lungs of the boy described in Antonella et al. I believe that these characteristics are important to determine the cause of the respiratory impairment in this case.Further, it is interesting to note that this phenomenon occurred in an 8-year-old boy. Only one in our 128 cases of fish-associated anaphylaxis was under 10 years of age, and this case was positive for the IgE specific to horse mackerel and mackerel.5 Therefore, the group I analyzed did not include cases of Anisakisanaphylaxis under the age of 10 years. The case described in Antonella’s manuscript does not appear to have undergone a specific IgE test or other skin tests. However, given the rarity of Anisakisanaphylaxis in this age group, anaphylaxis due to other culprits such as parvalbumin caused by fish ingestion should also be considered.Ryo Morishima MDDepartment of Neurology, Tokyo Metropolitan Neurological Hospital,Tokyo, JapanReferenceAntonella C, Stellario C, Aurelio M, Domenico S, Domenico S, Ilaria PP, et al. Acute scrotum in a 8-year-old Italian child caused by extraintestinal anisakiasis in a seaside area. Allergy 2020 [in press]Nieuwenhuizen NE. Anisakis – immunology of a foodborne parasitosis. Parasite Immunology 2016 Sep;38(9):548-57. doi: 10.1111/pim.12349. PMID: 27428817Alonso-Gómez A, Moreno-Accillo A, López-Serrano MC, Suarez-de-Parga JM, Daschner A, Cabañas R, et al. Anisakis simplex only provokes allergic symptoms when the worm parasitizes the gastrointestinal tract. Parasitol Res. 2004 Aug;93(5):378-84. doi: 10.1007/s00436-004-1085-9. PMID: 15221464Daschner A, Alonso-Gómez A, Cabañas R, Suarez-de-Parga JM, López-Serrano MC. J Allergy Clin Immunol. 2000 Jan;105(1 Pt 1):176-81. doi: 10.1016/s0091-6749(00)90194-5. PMID: 10629469Morishima R, Motojima S, Tsuneishi D, Kimura T, Nakashita T, Nishino H, et al. Anisakis is a major cause of anaphylaxis in seaside areas: an epidemiological study in Japan. Allergy. 2020 Feb;75(2):441-444. doi: 10.1111/all.13987. PMID: 31315145Shikino K, Ikusaka M. Anaphylaxis induced by Anisakis . Intern Med 2019 Jul 15;58(14):2121. doi: 10.2169/internalmedicine.2428-18. PMID: 30918192
The basophil activation test (BAT) is a functional assay that measures the degree of degranulation following stimulation with allergen or controls by flow cytometry and is directly correlated with histamine release. From the bell-shaped curve resulting from BAT in allergic patients, basophil reactivity (given by %CD63+ basophils) and basophil sensitivity (given by EC50 or similar) are the main outcomes of the test. BAT takes into account all characteristics of IgE and allergen and thus can be more specific than sensitization tests in the diagnosis of allergic disease. BAT reduces the need for in vivo procedures, such as intradermal tests and allergen challenges, which can cause allergic reactions of unpredictable severity. As it closely reflects the patients’ phenotype, it can potentially be used to monitor the natural resolution of food allergies and to predict and monitor clinical response to immunomodulatory treatments, such as allergen-specific immunotherapy and biologicals. Clinical application of BAT requires analytical validation, clinical validation, standardization of procedures and quality assurance to ensure reproducibility and reliability of results. Currently, efforts are ongoing to establish a platform that could be used by laboratories in Europe and in the USA for certification.
Background: The prevalence of tree nut allergy has increased worldwide, and cashew has become one of the most common food allergens. More critically, cashew allergy is frequently associated with severe anaphylaxis. Despite the high medical need, no approved treatment is available and strict avoidance and preparedness for prompt treatment of allergic reactions are considered dual standard of care. In the meantime, Phase III study results suggest investigational epicutaneous immunotherapy (EPIT) may be a relevant and safe treatment for peanut allergy and may improve the quality of life for many peanut allergic children. Objective: We aimed to evaluate the capacity of EPIT to provide protection against cashew-induced anaphylaxis in a relevant mouse model. Methods: A mouse model of IgE-mediated cashew anaphylaxis was first developed. Based upon this model, the efficacy of EPIT was evaluated by applying patches containing cashew allergens to cashew-sensitized mice. Cashew-specific antibody titers were measured throughout treatment. Treated mice were challenged orally to cashew and anaphylactic symptoms were monitored. Additionally, plasma levels of mast-cell proteases (mMCP)-1/7 were quantified from blood samples collected after challenge to evaluate IgE-induced mast-cell activation. Results: EPIT significantly decreased anaphylactic symptoms following challenge and increased cashew-specific IgG2a (equivalent of human IgG1). Interestingly, this protection was associated with a sharp decrease in mast-cell reactivity. Conclusion: We demonstrate that EPIT markedly reduced IgE-mediated allergic reactions in a mouse model of cashew allergy, which suggests that EPIT may be a relevant approach to treating cashew allergy.
This systematic review evaluates the efficacyand safety of omalizumab for chronic spontaneous urticaria (CSU). Pubmed, EMBASE and Cochrane Library were searched for RCTs. Critical and important CSU-related outcomes were considered. The risk of bias and the certainty of the evidence were assessed using GRADE. Ten RCTs including 1620 subjects aged 12 to 75 years old treated with omalizumab for 16 to 40 weeks were evaluated. Omalizumab 150 mg: does not result in clinically meaningful improvement(high certainty) of the urticaria activity score (UAS)7 (mean difference (MD) -5; 95%CI -7.75 to -2.25) and the itch severity score(ISS)7 (MD -2.15; 95% CI -3.2 to -1.1); does not increase (moderate certainty) quality of life (QoL) (Dermatology Life Quality Index (DLQI); MD -2.01; 95%CI -3.22 to -0.81); decreases (moderate certainty) rescue medication use (MD -1.68; 95%CI -2.95 to -0.4). Omalizumab 300 mg:results in clinically meaningful improvements(moderate certainty)of the UAS7 (MD -11.05; 95%CI -12.87 to -9.24), theISS7 (MD -4.45; 95%CI -5.39 to -3.51), and QoL (high certainty)(DLQI; MD -4.03; 95% CI -5.56 to -2.5); decreases (moderate certainty) rescue medication use (MD -2.04; 95%CI -3.19 to -0.88) and drug-related serious AEs (RR 0.77; 95%CI 0.20 to 2.91).
This systematic review evaluates the efficacy, safety and economic impact of dupilumabcompared to standard of care for uncontrolled moderate-to-severe atopic dermatitis (AD). Pubmed, EMBASE and Cochrane Library were searched for RCTs and health economic evaluations. Critical and important AD-related outcomes were considered. The risk of bias and the certainty of the evidence were assessed using GRADE. Seven RCTs including 1845 subjects > 12 years treated with dupilumab16 to 52 weeks were evaluated. For adultsthere is high certainty that dupilumabdecreasesSCORAD (MD -30,72; 95%CI -34,65% to -26,79%) and EASI-75 (RR 3.09; 95%CI 2.45 to 3.89), pruritus (RR 2.96; 95%CI 2.37 to 3.70), rescue medication (RR 3.46; 95%CI 2.79 to 4.30), sleep disturbance (MD -7.29; 95%CI -8.23 to -6.35), anxiety/depression (MD -3.08; 95% CI -4.41 to -1.75) and improves quality of life (MD -4.80; 95% CI -5.55 to -4.06). The efficacy for adolescents is similar. Dupilumab-related adverse events (AEs) slightly increase (low certainty). The evidence for dupilumab-related serious AE is uncertain. The incremental cost-effectiveness ratio ranged from 28,500 £ (low certainty) to 124,541 US$ (moderate certainty).More data on long term safety are needed both for children and adults, together with more efficacy data in the paediatric population.
Nanotechnology is science, engineering, and technology conducted at the nanoscale, which is about 1 to 100 nanometers. It has led to the development of nanomaterials, which behave very differently compared with materials with larger scales and can be applied in a wide range of applications in biomedicine. The physical and chemical properties of materials of such small compounds depend mainly on the size, shape, composition, and functionalisation of the system. Nanoparticles, carbon nanotubes, liposomes, polymers, dendrimers, nanogels, among others, can be nanoengineeried for controlling all parameters, including their functionalisation with ligands, which provide the desired interaction with the immunological system. However, undesired issues related to their toxicity and hypersensitivity responses have impeded more rapid health applications. Through interactions with the immune system, some of these nanostructures show promising applications as vaccines and diagnostics tools. Dendrimeric Antigens, Nanoallergens, and nanoparticles are potential tools for the in vitro diagnosis of allergic reactions. Glycodendrimers, liposomes, polymers, and nanoparticles have shown interesting applications in immunotherapy. There are wide panels of structures accessible, and controlling their physico-chemical properties would allow the obtainment of safer and more efficient compounds for clinical applications goals, either in diagnosis or treatment.
To the Editor, Severe asthma (SA) is a chronic disease affecting around 3-8% of adult asthma population in Europe, with the refractory form estimated to occur in 0.1% of the general population (1,2). SA is characterized by increased use of healthcare resources (i.e. emergency room/hospital admissions, access to intensive care units (ICU), use of biologics) due to exacerbations compared to the less severe form. In the current SARS-CoV-2 pandemic, there is an ongoing debate on the role of asthma and use of immunomodulating drugs, like corticosteroids and biologics, on COVID-19 outcomes. According to available data on COVID-19 hospitalizations, asthma seems to play little role on the clinical severity or access to health resources, unlike other chronic conditions such as hypertension, obesity and chronic obstructive pulmonary disease (3). However, to date, no information is available on the burden of SA on COVID-19 severity and hospitalization rates.A questionnaire was submitted to the Italian Registry of Severe Asthma (IRSA) network (4), assessing the prevalence and clinical characteristics of patients with SA who contracted COVID-19 during the outbreak in Italy (February 24th - May 18th 2020), and 41 out of 78 centers distributed evenly among different Italian regions participated to the survey (Figure 1a).Among the 558 subjects surveyed, 7 subjects contracted COVID-19 (1.25% of the national sample), with an average age of 54.5 years: 5 isolated at home/received home care (71.5%), while 2 subjects were admitted to the hospital (28.5%), none required accessed to ICU and no deaths were reported. All COVID-19 subjects with SA came from 2 regions of Northern Italy (6 Lombardy, 1 Emilia-Romagna, 3.7% of the regional population), all showing one or more comorbidities, and were treated with high-dose inhaled corticosteroids plus long-acting beta-2 agonists (ICS-LABA) and biologics (see Table 1).We then compared our results with data provided by the Italian Department for Civil Protection in the same time period from the affected geographic areas (5), and we observed that the frequency of COVID-19 among subjects referred to IRSA centers strongly correlated with the prevalence of SARS-CoV-2 infection in the corresponding province (Figure 1b). Furthermore, the hospitalization rate in COVID-19-SA subjects was not significantly different from the general population (24.1%, 23.6-24.6 95% C.I.; p=0.25, Chi-squared test). Lastly, we could not observe a significantly increased COVID-19 frequency in subjects undergoing high-dose ICS-LABA and biologics compared to SA treated with ICS-LABA alone (p=0.09, Fisher exact test).These findings from the IRSA registry offer some insights on the susceptibility to SARS-CoV-2 infection, access to healthcare resources and mortality by SA patients.Given the low prevalence of SA in Italy (2), we expected less COVID-19-SA cases per region than what reported by the IRSA survey. However, we observed that the geographic location of COVID-19-SA patients mostly reflected the bimodal distribution of the COVID-19 outbreak in Italy, mainly clustered in Lombardy and neighboring regions, where the highest cumulative COVID-19 cases were recorded (>500/100000 cases per inhabitants) (5). In these areas, the prevalence of positive cases by province also strongly correlated with the frequency of COVID-19-SA patients observed in each IRSA center (Figure 1b), suggesting that patients with SA most likely contract the infection when high circulation of the virus within the area of residence is present. The lack of positive cases reported in Southern regions further proves this hypothesis, and demonstrates the efficacy of the lockdown measures adopted to contain the further spread of the virus.Our results also suggest no increased risk of contracting COVID-19 in SA treated with biologics compared to ICS-LABA alone. Although there is currently no strong evidence that biologics used in asthma might affect the risk of contracting COVID-19, new evidence suggests a protective effect of inhaled corticosteroids against viral entry by ACE2 receptor downregulation, that are usually prescribed at a high dose in SA (6), thus a possible explanation to the lack of observed differences in our cohort.Despite the severity of asthma and reported comorbidities, no ICU admissions were reported, and hospital admissions in COVID-19-SA subjects did not differ from the median rate observed in the same geographic areas (5). Furthermore, we could observe no difference in the median monthly hospitalization rate of SA patients in 2019 compared to 2020 in Lombardy region where both hospital-admitted subjects reside (0.97 vs 0.9%, IRSA data).Our result is consistent with recent literature, showing that asthma in Western countries was not associated with an increased hospitalization rate and ICU admissions due to COVID-19 (3,8). It is still debated if a protective effect of Th2-inflammation in a significant proportion of asthma sufferers (7), or concomitant anti-inflammatory therapy could be the reasons for such outcomes (6). However, if asthma patients with COVID-19 require intubation, the duration of hospitalization was shown to be longer than average (8).As for the role of biologics in COVID-19 disease progression, we could not observe an increase in hospital admissions in patients with SA treated with biologics compared to the general population, with the majority isolating at home and requiring no additional treatment. Considering that, in areas with high prevalence of SARS-CoV-2 infection, 68.2% of SA subjects were treated with either omalizumab or mepolizumab, our observations further prove the safety of biologics during the COVID-19 pandemic.Lastly, we did not observe any deaths in our cohort, but we speculate that this outcome is most likely due to the small sample size and younger average age. In fact, advanced age seems to be the most determining risk factor on mortality due to COVID-19 compared to other causes. (9)Taken together, our results point at a neutral role of SA in the COVID-19 disease course and hospital admissions. One major strengths of our study is that, by using a fast and inexpensive tool, we could outline the salient features of severe asthma and COVID-19 at a national level, while the major weakness is the limited number of SA subjects diagnosed with COVID-19, that could lead to sampling bias and low accuracy. Further confirmation of these results with an increased sample size is therefore warranted