Title: Real-world evidence on the risk of cancer with anti-IL-5 and anti-IL-4Ra biologicalsAuthors : Diogo Mota1; Tiago Azenha Rama1, 2, 3, 4; André Moreira1, 2, 3, 4

In addition to known allergens, other proteins in pollen can aid the development of an immune response in allergic individuals. The contribution of the “unknown” protein allergens is apparent in phylogenetically related species where, despite of high homology of the lead allergens, the degree of allergenic potential can vary greatly. The aim of this study was to identify other potentially allergenic proteins in pollen of three common and highly related allergenic tree species: birch (Betula pendula), hazel (Corylus avellana) and alder (Alnus glutinosa). For that purpose, we carried out a comprehensive, comparative proteomic screening of the pollen from the three species. In order to maximize protein recovery and coverage, different protein extraction and isolation strategies during sample preparation were employed. As a result, we report 2500 - 3000 identified proteins per each of the pollen species. Identified proteins were further used for a number of annotation steps, providing insight into differential distribution of peptidases, peptidase inhibitors and other potential allergenic proteins across the three species. Moreover, we carried out functional enrichment analyses that, interestingly, corroborated high species similarity in spite of their relatively distinct protein profiles. We provide to our knowledge first insight into proteomes of two very important allergenic pollen types, hazel and alder, where not even transcriptomics data is available, and compared them to birch. Datasets from this study can be readily used as protein databases, and as such serve as basis for further functional studies.

Mass cytometry reveals unique subsets of T cells and lymphoid cells in nasal polyps from patients with chronic rhinosinusitis (CRS)

Role of activation of the coagulation system in the pathogenesis of urticariaTaro Yasuma,1 Corina N. D’Alessandro-Gabazza,1 Tetsu Kobayashi,2 John Morser,3 Esteban C Gabazza.1*1Department of Immunology,2Department of Pulmonary and Critical Care Medicine, Mie University Faculty and Graduate School of Medicine, and Mie University Hospital, Edobashi 2-174, Tsu, Mie 514-8507, Japan.3Division of Hematology, Stanford University School of Medicine, 291 Campus Drive, Stanford, CA 94305, United States*Correspondence: Esteban C Gabazza, MD, PhD, Department of Immunology, Mie University Graduate School of Medicine, Edobashi 2-174, Postal Code 514-8507, Tsu-city, Mie, Japan. Tel.: +81 59 231 5017; fax: +81 59 231 5225.E-mail:[email protected] count: 590

Allergy, Editorial

Medical Algorithm: Diagnosis and Managemen of Humoral ImmunodeficienciesAnna Šedivá1, Tomáš Milota1, Jiří Litzman2, Isabella Quinti3, ESID Clinical Working Party, EAACI Primary Immunodeficiency Working Group, Stephen Jolles4Department of Immunology, 2nd Faculty of Medicine Charles University, V Uvalu, University Hospital in Motol, Prague, Czech RepublicFaculty of Medicine, Masaryk University Brno, Czech Republic; Department of Clinical Immunology and Allergology, St Anne´s University Hospital, Brno, Czech RepublicDepartment of Molecular Medicine, Sapienza University of Rome, Rome, ItalyImmunodeficiency Centre for Wales, University Hospital of Wales, Cardiff, UKFor ESID Clinical Working Party:Isabelle Meyts, Department of Pediatrics, Leuven University Hospitals, Leuven, BelgiumSiobhan Burns, Institute of Immunity and Transplantation, University College London, London, United Kingdom; Department of Immunology, Royal Free London NHS Foundation Trust, London, United KingdomAuthor´s contributions:AS prepared the concept and wrote the manuscript, TM edited Figures and wrote the manuscript, JL designed Figures and revised manuscript, IQ designed Figures and revised the manuscript, IM revised manuscript, SB revised manuscript, ST edited Figures and wrote the manuscript.

Letter to EditorTo the EditorEgg-allergic children have higher ovomucoid (OVM)-specific IgD (sIgD) levels compared to the atopic controls.1 Within the egg-allergic group, children with higher levels of OVM-sIgD have a decreased risk of anaphylactic reactions. Ovalbumin (OVA)-sIgD increases in egg-allergic children desensitized by oral immunotherapy (OIT) but not in children unresponsive to OIT or with sustained unresponsiveness to OVA challenge.2 The natural development of tolerance and the acquisition of sustained unresponsiveness by OIT in egg-allergic children are associated with an increase in OVM-specific IgG4 (sIgG4) levels and a decrease in OVM-specific IgE (sIgE) levels.3 To elucidate the potential role of IgD in the outgrowing of egg allergy, we analyzed levels of egg white (EW)-, OVM-, and OVA-sIgD and sIgG4 in sera from 57 egg-allergic children (28 avoided all forms of egg in the diet (complete avoidance of egg: CAE), 18 were able to ingest at least 1/32 cooked whole egg but not one cooked whole egg (partial avoidance of egg: PAE), and 11 outgrew egg allergy (OGE)) and 23 healthy non-egg allergic children (non-egg allergy: NEA) (Table S1). The study was approved by The Research Ethics Committee of University of Fukui (#20110052), and written informed consent was obtained from the parent or guardians.EW-, and OVM-sIgE levels measured using ImmunoCAP (Thermo-Fisher Inc., MA) were higher in the CAE group, followed by the PAE, OGE, and NEA groups (Fig 1, Fig S1). The CAE group exhibited lower serum levels of EW- and OVA-sIgD compared to the NEA group and the PAE group, respectively, and had the lowest OVM-sIgD serum levels among all groups, suggesting that OVM-sIgD levels are associated with outgrowing egg allergy. We observed the lowest serum levels of EW-, OVA-, and OVM-sIgG4 in the CAE group, followed by the PAE and OGE groups. The ratio of OVM-sIgD to OVA-sIgD increased as children outgrew egg allergy, whereas the ratio of OVM-sIgG4 to OVA-sIgG4 did not change. Thus, the production of OVM-sIgD differs from OVM-sIgG4 as children naturally outgrow egg allergy.High-affinity, but not low-affinity, IgE is known to cause anaphylaxis.4 High-affinity IgE is derived from memory IgG1+ B cells, whereas low-affinity IgE is derived from naïve IgM+IgD+ B cells. Considering class switching pathways, switching direction from IgM to IgD, and from IgG1 to IgE or IgG4, elevated OVM-sIgD levels might be associated with low-affinity OVM-sIgE levels as children outgrow egg allergy, resulting in hypo-responsiveness to OVM.A recent study found that OVM-sIgE avidity was more effective at differentiating clinically reactive egg-allergic patients from those tolerant of heated egg compared to EW-sIgE.5 The ratio of OVM-sIgE to OVM-sIgD or sIgG4 in the CAE group was significantly higher compared to the PAE, OGE, and NEA groups (Fig 2). Receiver operating analysis revealed that the ratio of OVM-sIgE to OVM-sIgD discriminated non-tolerant from partially-tolerant egg-allergic patients with the largest area under the curve (AUC = 0.965) compared with levels of OVM-sIgE or the ratio of OVM-sIgE to OVM-sIgG4. The optimal cutoff for the ratio of OVM-sIgE to OVM-sIgD had 86.5% sensitivity and 96.4% specificity to identify high-risk subjects (Table S2).There are several limitations to this study. First, there was a small number of patients. Second, all children were only challenged with heated egg and were instructed to avoid egg of any form if they tested positive with less than 1/32 cooked whole egg. Finally, there was a lack of trajectory of sIgD levels during natural tolerance development.In conclusion, the ratio of OVM-sIgE to OVM-sIgD is a useful marker to identify high-risk egg-allergic patients capable of ingesting a low-dose of cooked whole egg who might be a good candidate for low-dose OIT.

A document by Laura Haya. Click on the document to view its contents.

I thank Dres. Alnaes and Helnes Bergen for their stimulating comment on my medical algorithm on the Diagnosis and Treatment of Radiocontrast Media Hypersensitivity.1 In their comment, they raised attention to the possible addition of desensitization to radiocontrast media (RCM) management, which was not depicted in the algorithm.2 I have been well aware of several reports on desensitization and have already discussed them in a previous paper, however commented there that “successful desensitization of RCM has been reported for immediate hypersensitivity reactions to RCM, but it is only used anectodically” and concluded not to include this procedure into the algorithm.3In addition to the two papers on desensitization to RCM cited by Dr. Alaes, also a handful other cases have been published, some of them older. To my knowledge, at least as far as I can access these case reports, in none of these patients a proper allergy diagnosis and management has been performed and in most, if not all of these patients, desensitization probably was unnecessary. In the described cases, skin testing has not been performed or was even negative indicating a higher probability for a non-allergic immediate hypersensitivity reaction (IHR), in the history before desensitization was performed in several cases the RCM was not changed, but the same not tolerated RCM was given again and radiologists in vain relied on premedication to prevent recurrent attacks, and no skin test-negative RCM was identified and used. None of the cases published convinced me of the need for desensitization. Performing the examination with a skin test-negative RCM would with a high probability be successful.4 I would expect the success of desensitization was rather due to changing to a different isoosmolar RCM (and probably not to adding premedication) than the desensitization procedure itself, as alone changing the implicated RCM to another one in one study reduced the risk of recurrent IHR by 67.1% (odds ratio: 0.329; P = 0.001), whereas steroid premedication did not show protective effects.5Our group of European Network on Drug Allergy experts have highlighted that rapid desensitization is a procedure that can be used to provide a temporary tolerance to a first-line drug when no alternative is available.6 This implies for RCM hypersensitivity that using a skin-test-negative RCM for the next examination as an alternative drug is next step and not immediate desensitization. One problem with desensitization is that too many doctors employ it uncritically and without prior proper allergy workup, best with drug provocation test. The high rate of successful desensitizations without prior confirmation of drug hypersensitivity in the literature is in part explained by the fact that many of those patients would not have reacted anyway. I have yet to find convincing evidence to add desensitization as a standard therapeutic option to the RCM management algorithm.Having said this, I am eagerly following up the literature on RCM desensitization with great interest to be prepared, should I encounter an own patient, who would react severely to an alternative skin test-negative RCM after following the algorithm. Until now, colleagues and I have not met such a patient, however, I would seriously consider desensitization as an option in such a situation. Thus, I thank Dres. Alnaes and Helsen Bergen for bringing up that interesting topic for discussion.

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.

Background: The SQ tree SLIT-tablet has recently been approved for treatment of tree pollen allergy. Health care workers should be provided with detailed safety data for clinical use. Objective: To assess the tolerability and safety of the SQ tree SLIT-tablet in adults and adolescents. Methods: Safety data were pooled from two phase-II and one phase-III double-blinded, randomized, placebo-controlled trials including adults and adolescents with allergic rhinitis and/or conjunctivitis treated before and during one pollen season once-daily with the SQ tree SLIT-tablet (12 SQ-Bet) or placebo. Results: The most frequently reported IMP-related AEs with 12 SQ-Bet were oral pruritis (39% of subjects) and throat irritation (29%). IMP-related AEs were mainly mild or moderate in severity, and the majority resolved without treatment and did not lead to treatment interruption/discontinuation. With 12 SQ-Bet, oral pruritus was more frequent among PFS subjects (45%) than in subjects without PFS (29%). A greater proportion of PFS subjects interrupted treatment (19%) than subjects without PFS (7%). The 12 SQ-Bet did not seem to induce an increased risk of asthma: 7 events were reported in 7 subjects with 12 SQ-Bet and 11 in 10 subjects with placebo. No differences were seen in the risk of moderate to severe IMP-related AEs regardless of age, PFS status and asthma medical history. Conclusions: The 12 SQ tree SLIT-tablet was well tolerated in tree pollen allergic subjects with no major safety concerns detected. This safety profile supports daily at-home sublingual administration once the first dose is tolerated when administered under medical supervision.

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

Similar IgE Binding Patterns in Gulf of Mexico and Southeast Asian Shrimp Species in US Shrimp Allergic PatientsSara Anvari1,2*, Shea Brunner1,2*, Karen Tuano1,2, Brenda Bin Su1,2, Shaymaviswanathan Karnaneed3, Andreas L. Lopata3, Carla M. Davis1,21Baylor College of Medicine, Texas Children’s Hospital, Department of Pediatrics, Section of Immunology, Allergy and Retrovirology, Houston, Texas2Baylor College of Medicine, William T. Shearer Center for Human Immunobiology, Houston, Texas3James Cook University, Australian Institute of Tropical Health and Medicine, Centre for Molecular Therapeutics, Douglas, QLD, Australia*co-first authors

Addressing Beta-lactam Allergy: A Time for actionElizabeth J. Phillips, MD, FIDSA, FAAAAI, Pascal Demoly, MD, PhD, Maria J Torres, MD, PhD1 Department of Medicine, Center for Drug Safety and Immunology, Vanderbilt University Medical Center, Nashville Tennessee USA, 2Institute for Immunology & Infectious Diseases, Murdoch University, Murdoch Australia, 3Division of Allergy, Department of Pulmonology, University Hospital of Montepellier, and IDESP, Univ. Montpellier – Inserm, Montpellier France,4Allergy Unit, Hospital Regional Universitario de Malaga-IBIMA-BIONAND-ARADyAL, and Departmento de Medicina, Universidad de Malaga, Malaga, SpainCorrespondence:Elizabeth J. Phillips, MD, FIDSA, FAAAAICenter for Drug Safety and ImmunologyVanderbilt University Medical Center1161 – 21st Avenue SouthNashville, TN 37232(615) 322-9174 (tel)[email protected] is now 93 years since the discovery of penicillins, and over 75 years since the first use of penicillin. We have entered yet another wave of challenges plagued with antibiotic resistance accelerating at a rate that well exceeds that of new antibiotic development. In the face of these uphill battles, 8-15% of a global population who has had access to care is labeled as penicillin allergic.1 In the United States (US) there are at maximum 6000 specialists who practice allergy out of a total of 700,000 practicing physicians, and not all allergists are proficient in and practice drug allergy. Conservatively out of 30,000,000 who are labeled as penicillin allergic at any one time in the US, this would mean that each allergist would need to delabel a minimum of 6000 patients. In Europe and the United Kingdom, the figures are proportionately identical, with some differences between countries. Even if all patients had equal access to care, this type of scalability remains impossible. This overwhelming burden that threatens to negatively impact healthcare through delays in treatment, higher healthcare utilization and cost, less effective treatment and increased antibiotic resistance and Clostridioides difficile infection, demands a risk-based approach that simplifies the penicillin allergy delabeling process and establishes bridges with non-allergists.1, 2What have we learned that now makes the population level goal of penicillin delabeling achievable? First off, prevention is better than cure. We should critically examine pediatric populations for antibiotic use to address over-prescription of antibiotics including penicillins for viral infections. We should avoid labeling children with benign delayed exanthems that occur in the setting of a likely viral infection as penicillin allergic. When continued treatment is necessary we should in fact encourage “treating through” such reactions. When a label of penicillin allergy seems inevitable in a child we should address this label early and pay particular attention to antibiotic stewardship. New data on serum sickness-like reaction suggests that many of these are likely virally mediated and do not reproduce on ingestion challenge.3 Community based education programs can help disseminate timely information on penicillin allergy to dispel myths and alleviate fears. A label of penicillin allergy should be both viewed and approached as a threat to both individual and public health. On a public health level addressing penicillin allergy should be seen as a broad stewardship tool that provides a level of herd protectiveness against antibiotic resistance. On an individual level a label of penicillin allergy should be approached with the same routineness as any other preventative health check, and primary care physicians and providers should be trained to understand and manage low-risk penicillin allergy labels.4 Patients should regularly discuss their drug allergy passport with their healthcare providers such as pharmacists and physicians. Allergy passports should enable interoperability, high traceability and time-stamped information solving the problem of frequent unavailability and inaccuracy of drug allergy information.5 Risk stratification should occur and if in a low-risk category a patient should be given the option of direct oral challenge and delabeling. Risk stratification to identify by clinical history the low-risk penicillin allergic patients who would be appropriate for simple procedures is key. Several mechanisms now exist to risk stratify those labeled as penicillin allergic in routine clinical practice. These clinical prediction rules provide an evidence base to identify the majority of low-risk penicillin allergy labeled patients who are at low risk for rechallenge reactions.6, 7 In current practice it is likely that less than 1% of such low-risk patients will be at risk for a reaction on ingestion challenge.1, 8To make widespread penicillin allergy delabeling an achievable and scalable goal we must be convinced of the safety of direct ingestion challenges. A randomized study allocated children 5 years or older with low-risk cutaneous reaction to penicillin skin testing followed by amoxicillin challenge versus 2 step direct oral challenge with amoxicillin with tolerance of amoxicillin of 96% of those with direct challenge and only minor reactions in the remainder.9These results have recently been confirmed in an European population of children.10 Aside from the inconvenience and potential need for specialty assessment, for very low-risk patients, the use of skin testing would be expected to perform poorly considering their low pre-test probability of a reaction. Several other studies have demonstrated that a single or two-step direct ingestion challenge with penicillins such as amoxicillin is a safe and practical strategy to remove a label of penicillin allergy.11 Although there is evidence to support the use of risk stratification tools to delabel penicillin allergy under allergist guidance, we require an educational program on drug allergy for primary care physicians as well validation of these risk stratification tools, to show that low-risk penicillin delabeling can be achieved in this setting.Even in the face of risk stratification and safety of direct ingestion challenge, populations are not equal in terms of their medical risk or antibiotic needs. Intuitively populations that serve to benefit from penicillins and other beta lactams have been shown to have inferior outcomes when labeled as penicillin allergic that would benefit from a delabeling intervention. This includes the association of penicillin allergy label and use of an alternative antibiotic with post-operative surgical site infections.12 Other settings where research has shown feasibility in delabeling include children in the emergency department, critically ill populations with high antibiotic needs, and pregnant women where the high rates of surgical delivery and group B Streptococcal colonization in pregnancy create a high demand for penicillin and cephalosporins as safe firstline drugs.1, 13, 14 Increasingly, assessment of unverified penicillin allergy has been recognized as an antibiotic stewardship intervention in immunocompromised states such as transplant and cancer where populations have much to gain by being delabeled.15There is a “time for action” for removal of penicillin allergy labels on a population level but how do we achieve widespread implementation (Figure 1)? Policy changes should be driven by collaboration with Infectious diseases specialists and allergists who should join forces to pair antibiotic allergy management with antibiotic stewardship. In the community we need to educate parents and pediatricians to make them aware of the hazards of both unnecessary antibiotics and penicillin allergy labels for mild rashes that are often related to a viral infection and unlikely to recur. Primary healthcare providers should be given greater incentives to delabel penicillin allergic patients at the point-of-care and armed with decision support tools to facilitate risk stratification. For those whose history is not consistent with allergy this could include direct delabeling without testing. In the future, evidence may support that routine direct ingestion challenge with a penicillin and delabeling is safe in the primary care setting. Finally, by off-loading low-risk reactions to primary care providers we can then prioritize care of the patients with a higher-risk allergy and/or medical history by engagement with specialists who can provide more in-depth assessments and give them the best antibiotic options.Figure 1: Addressing Beta-lactam Allergy: An Implementation Roadmap: There are currently many missed opportunities for community members and healthcare providers to take action forward on the “penicillin allergy delabeling” movement. This includes not only active measures to delabel patients by history and direct oral challenge and to identify high risk patients for prioritized penicillin allergy delabeling but also preventive measures to avoid unnecessary use and exposure to antibiotics and avoidance of unnecessary labeling in those with mild rashes of likely viral origin.

Background Approximately 70 % of individuals allergic to birch pollen (Bet v 1.01 [Bet]) develop a secondary food allergy (e.g. hazelnut: Cor a 1.04 [Cor]), due to allergen cross-reactivity. However, standard immunotherapy for type I allergies often does not improve the food allergy sufficiently. We analyzed the allergen-specific and cross-reactive suppressive capacity of primary human regulatory T cells (Treg) induced by autologous IL-10-modulated dendritic cells (IL-10 DC) in vitro and in vivo. Methods CD4 + T cells of patients with birch pollen and associated hazelnut allergies were differentiated into Bet-specific or non-specific induced Treg (iTreg). After Bet- or Cor- specific restimulation the phenotype, proliferation and suppressive capacity of iTreg subsets were analyzed. iTreg function was further investigated in humanized mouse models of airway and intestinal allergy, generated by engraftment of peripheral blood mononuclear cells from allergic donors into immunodeficient animals. Results After IL-10 DC priming and allergen-specific restimulation (Bet or Cor) non-specific control iTreg remained anergic, whereas Bet-specific iTreg proliferated extensively and exhibited a regulatory phenotype (enhanced expression of CTLA-4, PD-1, TNFR2, IL-10). Accordingly, activated Bet-specific iTreg displayed a high capacity to suppress Bet- and Cor-induced responder T H2 cell responses in vitro, indicating induction of both allergen-specific (birch) and cross-reactive tolerance (hazelnut). In vivo, the beneficial effect of Bet-specific iTreg was verified in humanized mouse models of allergic airway and intestinal inflammation, resulting in reduced allergen-induced clinical symptoms and immune responses. Conclusion Human IL-10 DC-induced iTreg facilitate allergen-specific and cross-reactive tolerance. Therefore, they are potential candidates for regulatory cell therapy in allergic and autoimmune diseases.

Artemisia annua sublingual immunotherapy in children with seasonal allergic rhinitis To the Editor,Artemisia pollen is the main aeroallergen of seasonal allergic rhinitis (SAR) in summer and autumn.1,2Artemisia annua Allergens Sublingual Immunotherapy (SLIT) Drops (Zhejiang Wolwo Bio-Pharmaceutical Co., Ltd., Zhejiang, China, National Drug Approval No.: S20210001) is the only standardized SLIT preparation approved in China for treatingArtemisia-induced allergic rhinitis with or without conjunctivitis (AC).3 In this study, we aimed to evaluate the safety and efficacy of A. annua- SLIT in children with SARs.Pediatric patients with at least a two-year clinical history ofArtemisia pollen-induced SAR with or without AC from Inner Mongolia were included in this randomized, double-blind, placebo-controlled, single-center clinical trial and randomized to receive A. annua -SLIT or placebo at a 2:1 ratio for approximately 28 weeks. The combined score of medication and rhinitis symptoms (CSMS; primary endpoint) and combined score of medication and rhinoconjunctivitis symptoms (CSMRS; secondary endpoint) were recorded to evaluate efficacy; adverse events (AEs) were reported to assess safety.Fifty-seven eligible patients aged 4–18 years were randomized into the SLIT (n=38) and placebo (n=19) groups (Figure 1). Finally, 54 patients (SLIT group: n=36; placebo group: n=18) completed the study with 3 patients withdrew by themselves. No significant differences were observed between the groups in terms of sex, age, atopic status, comorbidity of other allergic diseases, and CSMS and CSMRS scores in the previous pollen season (P >0.05, Table S1).The 2019 pollen season in Inner Mongolia was from 20th July to 7th September (50 days; Figure 2A). The temporal variation of daily CSMRS in both groups showed a similar trend of positive correlation with pollen concentration throughout the pollen season (SLIT group: r=0.66, 95% CI: 0.53–0.76; placebo group: r=0.68, 95% CI: 0.56–0.77). The SLIT group showed significant improvements in CSMS (1.55±0.81 vs. 1.97±0.73) and CSMRS (1.46±0.75 vs. 1.88±0.75) compared with the placebo group (P <0.05, Figure 2B–C). Fifty-three (98.1%) patients experienced AEs [35, SLIT group; 18, placebo group] (Table S2). All AEs were mild or moderate and resolved without any action or by adjusting the dose of the study drug. There were no significant differences in the incidence and severity of AEs between the groups (P >0.05). Epinephrine use was not reported, and no patients withdrew from the trial because of AEs. Furthermore, 94.4% and 100% of patients in the SLIT and placebo groups, respectively, experienced treatment-related AEs (TRAEs), which frequently occurred in the nose, eyes, throat, and tongue in both groups (P >0.05, Figure 2D). The common TRAEs in children with SLIT are shown in Figure 2E. Most TRAEs in the SLIT group were mild, similar to those in the placebo group.To our knowledge, this is the first study to report the efficacy and safety of A. annua -SLIT in a Chinese pediatric population. Our results showed a consistent trend of clinical efficacy improvements withA. annua -SLIT in children similar to those in adults.4 Recently, a cumulative AE incidence of 93.0% was reported with ragweed SLIT in children and adolescents, with no serious AEs.5 The incidence of AEs in our study were comparable to those in the previous study. Lou et al. found that the most common TRAEs in adults with A. annua -SLIT were mild or moderate.4,6 Our results showed a safety profile similar to that in adults. No new safety signals emerged, and no throat irritation was observed in adults.In conclusion, 28-week A. annua -SLIT treatment was effective and safe for children with SAR, with no major safety concerns. Investigating the benefits of A. annua -SLIT in children will not only expand its application for treatment but also provide the basis for intervention in the early phase of SAR.

Needle-free Epicutaneous For t 2 DNA Vaccine is Effective for Preventing and Treating Biting Midge (Forcipomyia taiwana) allergy in a murine modelTo the Editor,Allergen-specific immunotherapy (ASIT) remains the only treatment capable of inducing immune tolerance to the corresponding allergen and potentially treating the root cause of the allergic disease.1 As the treatment course of protein-based vaccines for ASIT is time-consuming, an easily administered epicutaneous anti-allergic DNA-based vaccine is an attractive method, especially in light of the COVID-19 pandemic.2The biting midge, Forcipomyia taiwana , is the most prevalent cause of biting insect allergy in Taiwan. It is a tiny hematophagous midge that attacks en masse. As many as 60% of exposed individuals develop allergic reactions to the bites.3 The midge is widely distributed throughout Taiwan and southern China. For t 2 is the most predominant,with 75% of midge-allergic patients showing specific IgE to For t 2.4 Allergic reactions to midge bites are not limited to humans but also seen in livestock, such as horses, cattle, sheep, and donkeys, causing significant veterinarian problems.E.coli -expressed For t 2 recombinant protein (rFor t 2) was used as an allergen to sensitize and challenge the mice.5For t 2-encoding fragment (GenBank accession EU678971) was amplified by PCR. The PCR products were subcloned into pVAX1 (Life Technologies, Carlsbad, CA) . The experiments were designed using two approaches: therapeutic and prophylactic (Fig 1). The therapeutic approach is to imitate ASIT in human with established allergy while the prophylactic approach to non-allergics. Twenty-five μg For t 2 DNA was determined as the optimal dose after dose-finding experiments (Supplementary Fig S1). For each treatment, the hair of the abdominal area of the mice was removed using a depilatory,tape-stripped,then patched with 25 μg For t 2 DNA vaccine for one hour and removed.A total of three treatments were given spaced one week apart (Fig 1 and Fig S2). For t 2 proteins were detected in the patched skin and the immune organ spleen at 24 hoursand had significantly increased at 48 hours after last treatment (Fig S3). Scratch bouts after rFor t 2 challenge were used as a clinical surrogate of itch. We measured For t 2-specific IgE, IgG1 and IgG2a in the sera as well as mRNA and proteins of IL-13, interferon-gamma, IL-10, and FOXP3 in the culture supernatants of splenocytes after stimulation with various doses of rFor t 2 at 37℃ for 3-5 days by ELISA and real-time quantitative PCR. Histopathology of the challenged skins was examined.After epicutaneous DNA vaccination, the allergen-induced itchin both groups significantly improved, and For t 2-specific IgE and IgG1/IgG2a ratio decreased significantly at week 6 or week 8 (Fig 2). Levels of mRNA and protein of IL-13 decreased significantly, but IFN-gamma and IL-10 remained unchanged. Expression of FOXP3 mRNA increased (Fig 2, protein data not shown). Eosinophils infiltration in the challenged skin significantly decreased (Fig S4).This is the first study to demonstrate an epicutaneous needless anti-allergic DNA vaccine that effectively treats an established allergic condition and prevents the development of an allergic disease using biting midge allergy as a model. After epicutaneous DNA vaccination, in addition to allergen-induced itch, the changes of multiple biomarkers suggest that immune tolerance was induced after the epicutaneous DNA vaccine.Our data show that though the molecular weight of the For t 2 DNA vaccine is as high as 4000 base pairs, it can penetrate the dermal barrier and translate the corresponding protein in the targeted skin and the spleen of the vaccinated mice. It is possible that the DNA vaccine passes the epidermis via the hair follicles as the skin is tape-stripped before epicutaneous vaccination.6The mode of this anti-allergic epicutaneous DNA vaccine may potentially be used in other specific immunotherapies for other allergens.Mey- Fann Lee1Chi-Sheng Wu2 Shyh-Jye Lin3Yi-Hsing Chen2,4*1Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan2Division of Allergy, Immunology and Rheumatology, Taichung Veterans General Hospital, Taichung, Taiwan3School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan4School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan

Subcutaneous adipose tissue (SAT) is the deepest component of the three-layered cutaneous integument. While mesenteric adipose tissue-based immune processes have gained recognition in the context of the metabolic syndrome, SAT has been traditionally considered primarily for energy storage, with less attention to its immune functions. SAT harbors a reservoir of immune and stromal cells that significantly impact metabolic and immunologic processes not only in the skin, but even on a systemic level. These processes include wound healing, cutaneous and systemic infections, immunometabolic and autoimmune diseases, inflammatory skin diseases, as well as neoplastic conditions. A better understanding of SAT immune functions in different processes, could open avenues for novel therapeutic interventions. Targeting SAT may not only address SAT-specific diseases but also offer potential treatments for cutaneous or even systemic conditions. This review aims to provide a comprehensive overview on SAT’s structure and functions, highlight recent advancements in understanding its role in both homeostatic and pathological conditions within and beyond the skin, and discuss the main questions for future research in the field.