Frequency of Euroglyphus maynei sensitization in respiratory allergies: a real-life study with bioinformatic analysis and geographical exploration of allergen prevalence.

BACKGROUND: Dermatophagoides pteronyssinus and Dermatophagoides farinae belong to the family Pyroglyphidae (subfamily: "Dermatophagoidinae") and have the respective allergenic proteins of Der p1, Der p2, and Der p23 and Der f1 and Der f2. Euroglyphus maynei, belongs to the family Pyroglyphidae (subfamily: "Pyroglyphinae") and its main allergenic protein is Eur m1, a source of sensitization. Sensitization to D. pteronyssinus and D. farinae is assessed through skin tests, while sensitization to E. maynei is assessed less frequently. OBJECTIVE: This experimental work aims to analyze the prevalence of sensitization to E. maynei in patients with respiratory allergies treated at M. Albanesi Allergy and Immunology Unit in Bari, Italy, and the sequence homology of major allergenic proteins of E. maynei with D. farinae and D. pteronyssinus was analyzed. METHODS: In this real-life study, 65 patients were enrolled. In particular, patients with respiratory allergy were subjected to skin prick tests for common respiratory allergens, including Euroglyphus maynei. The sequence homology analysis was performed between the major allergenic proteins of E. maynei and those of D. pteronyssinus and D. farinae. RESULTS: Sensitization to E. maynei accounts for 41.5% of patients. All patients with E. maynei sensitization had concomitant sensitization to D. farinae and D. pteronyssinus. The analysis of sequence homology of Der p1 and Der f1 proteins with the sequence of Eur m1 protein demonstrated an identity of 84.4% and 86%, respectively. CONCLUSIONS: Nearly 50% of house dust mites-sensitized patients have a concomitant sensitization to E. maynei. The cross-sensitization could be due to Der f1, Der p1, and Eur m1 similarity.

Dupilumab elicits a favorable response in type-2 inflammatory comorbidities of severe atopic dermatitis.

BACKGROUND: This case is the first report describing rapid, successful treatment of severe atopic dermatitis (AD) and comorbid type-2 inflammatory diseases in the same patient, with dupilumab treatment, with no side-effects. CASE PRESENTATION: We report on effects of dupilumab in a patient with severe AD, a long-standing history of a mild, perennial allergic rhino-conjunctivitis, moderate asthma and chronic rhinosinusitis with nasal polyps (CRSwNP). CONCLUSIONS: Patients suffering from AD, asthma, allergic rhinitis and CRSwNP may be eligible for dupilumab single treatment that is possibly advantageous also from the pharmaco-economic standpoint.

Cost-effectiveness of grass pollen allergen immunotherapy in adults.

BACKGROUND: Major scientific societies, such as the EAACI or the AAAAI, do not express any suggestion on which form of allergen immunotherapy (AIT) is to be preferred (subcutaneous immunotherapy, SCIT, vs sublingual immunotherapy, SLIT). This choice could depend on their relative pharmacoeconomic value. OBJECTIVE: To assess the cost-effectiveness of AIT for grass pollen, administered as SCIT or SLIT. METHODS: We created a Markovian Model, to evaluate, in a hypothetical cohort of adult patients suffering from moderate-to-severe rhino-conjunctivitis with or without allergic asthma, the cost-effectiveness of SLIT (tablets, Grazax® and Oralair® ) or SCIT (various currently available products, plus indirect nonmedical costs, such as travel and productivity costs) in addition to pharmacological therapy, assuming a 9-year horizon to capture AIT long-term effects. The incremental cost-effectiveness ratio (ICER) was calculated assuming pharmacological therapy as the reference comparator. RESULTS: In the base case, SCIT was slightly more expensive, but more effective than SLIT, being the most cost-effective option (ICER for SCIT, €11 418; ICER for SLIT, €15 212). ICERs greater than €120 000 for both SCIT and SLIT were demonstrated in a scenario assuming that low treatment persistence rates, which are common in real-life, lead to absence of long-term AIT clinical benefit. Considering indirect nonmedical costs SLIT resulted more cost-effective than SCIT (ICER for SCIT, €17 318; ICER for SLIT, €15 212). CONCLUSION: In daily practice, AIT for grass pollens may be a cost-effective option only in patients with low discontinuation rates. SCIT, which is less affected by this limitation than SLIT, seems the most cost-effective AIT form.

Benralizumab improves patient reported outcomes and functional parameters in difficult-to-treat patients with severe asthma: Data from a real-life cohort.

In the last decade, an increasing number of randomized controlled trials (RCTs) on biologic therapy in patients with severe asthma have included patient-reported outcomes (PROs) as secondary efficacy measures. The majority of these RCTs showed a benefit in symptoms and quality of life. However, the magnitude of this benefit remains uncertain, because it rarely exceeded the minimal important difference (MID), owing to a significant improvement in the control group (placebo effect). Real-life studies on biologic therapies assessing PRO are scarce. They may support and integrate RCT results through their different experimental design. This real-life retrospective study provides data on 15 patients with difficult-to-treat severe eosinophilic asthma treated with benralizumab up to 6 months. Asthma quality of life questionnaire (AQLQ) and asthma control test (ACT) were assessed and administered at each visit to minimize the Hawthorne effect. Changes in general accepted efficacy measures, such as forced expiratory volume in 1 s (FEV1), peak expiratory flux (PEF), exacerbation rate and blood eosinophils, from baseline were also assessed. AQLQ and ACT improved from 3.9 ± 0.4 to 5.2 ± 0.4 and from 15.6 ± 5.7 to 18.1 ± 5.6, respectively. FEV1 increased of about 250 ml (+14%). PEF increased from 288 ± 107 to 333 ± 133 l/min. The number of exacerbations requiring OCS courses decreased from 2.8 ± 2.2 to 0.5 ± 0.8. Eosinophil counts dropped to 25.6 ± 15 cells/microliter. In conclusion, most patients reported improvements in AQLQ and ACT greater than MID, suggesting that these outcome represent a sensitive tool in real-life effectiveness studies. Our approach reduced the limitations of transition questions and the Hawthorne effect, increasing findings reliability.

Desensitization in Iron Product Allergy.

Iron deficiency is the main cause of anemia in both sexes, with women being more commonly affected. Iron therapy is currently considered an effective and safe remedy to replenish the iron storages. Iron can be administrated both orally and intravenously. In particular, intravenous (IV) iron therapy is widely used when oral iron preparations are either not tolerated or ineffective. Indeed, IV iron improves iron stores more rapidly. Two main immunological responses have been described for iron hypersensitivity reactions (HSRs): IgE-mediated allergy and complement activation-related pseudo-allergy. Here, we report 3 cases of adult patients with iron allergy, who were successfully treated with two different desensitization procedures, respectively. Analysis of these cases demonstrates that, in the presence of HSRs to iron products, desensitization is an effective and safe procedure that prevents treatment discontinuation and hence allows therapeutic target achievement.

Safety of measles, mumps, and rubella vaccine in egg allergy: in vivo and in vitro management.

BACKGROUND: Egg allergy is the second most prevalent form of food allergy in childhood. In spite of the evidence accumulated, inoculating egg allergy children with attenuated vaccines grown on chick embryo cell cultures, such as the measles, mumps, and rubella (MMR) vaccine, is regarded (erroneously) as potentially dangerous or even anaphylactogenic, by many. An issue perceived as particularly conflicting also by Health Professionals. CASE PRESENTATION: A 15-year-old boy, with a history of severe egg allergy in early infancy, who was still sensitized to egg allergens, including baked egg, had never received MMR vaccination, in fear of possible anaphylaxis, in spite of the fact that this vaccination is mandatory in the first year of life, in Italy. Because of that, he was not allowed to attend school, longer, and was referred to us in order to assess the potential risk of MMR vaccination. Upon thorough allergologic workup, sensitization to MMR vaccine components was excluded by an in vivo approach, consisting in skin prick tests, intradermal tests, and subcutaneous injection test, corroborated by vaccine-specific B-lymphocyte proliferation assay, ex vivo. T-cell proliferation in response to MMR vaccine was also excluded. Eventually, the boy was inoculated with MMR vaccine and was readmitted to school. CONCLUSIONS: The diagnostic strategy adopted appears feasible and easy-to-perform and may be adopted in controversial cases (as the one reported), characterized by previous severe allergic reactions to egg. The B-lymphocyte proliferation assay we developed may represent a useful and reliable tool not only in research but also in clinical practice.

Maintenance-Phase Subcutaneous Immunotherapy with House Dust Mites Induces Cyclic Immunologic Effects.

BACKGROUND: Subcutaneous immunotherapy (SCIT) is an effective treatment of respiratory allergies including house dust mite (HDM) and Hymenoptera venom allergy. During the build-up phase, the allergen is administered weekly at increasing doses, while during the maintenance phase, it is administered at a fixed high dose every 4 weeks. Upon SCIT injection, the allergen is driven to the draining lymph nodes where it most likely induces an immune response. Immunologic changes are thus supposedly induced at each injection. OBJECTIVES: It is now established that SCIT induces tolerance in the long term, but the precise underlying immunologic mechanisms remain unclear. Therefore, we wanted to analyze the immunologic changes induced in both innate and adaptive immune cells at each individual SCIT administration during the maintenance phase in HDM-allergic patients. More specifically, we wondered whether the changes in regulatory T cell (Treg) and IgE+ B cell percentages, which are observed at the end of a 3-year course of SCIT, already occurred during the maintenance phase and whether these possible changes were sustained. METHODS: We enrolled 6 patients suffering from HDM allergic rhinitis and undergoing maintenance HDM SCIT for 18-24 months. The same SCIT extract was used for all patients. We collected blood samples at 5 time points: T1 (immediately before a given SCIT injection), T2 (9 days after T1), T3 (29 days after T1 and right before the successive administration), T4 (39 days after T1), and T5 (61 days after T1 and just before the next injection). Six non-allergic age-matched healthy individuals were used as controls. Using flow cytometry, we assessed the following cell subsets in peripheral blood mononuclear cells: CD4 and CD8 T cells, Tregs, B cells, IgE+ B cells, NK and NKT cells, and total and activated basophils. RESULTS: HDM-allergic patients displayed increased percentages of CD4 and CD8 T cells and NK cells compared to healthy controls. In contrast, NKT cells, total B cells, and basophils were diminished. These differences were maintained throughout the time course and seemed to be independent of the periodical SCIT injections. On the contrary, Treg percentages were significantly reduced in all HDM-allergic patients at T1. However, they increased at T2 and T4 (9 days after each SCIT injection) but decreased again at T3 and T5, just before the next one, resulting in cyclic changes. IgE+ B cells were significantly increased at T1, even more increased after each administration (T2, T4), and went back to their initial levels at T3 and T5, also resulting in a cyclic pattern. CONCLUSIONS: Our data suggest that during the SCIT maintenance phase, cycles of expansion/contraction of Tregs and IgE+ B cells occur at each SCIT injection. Therefore, the sustained induction of immune tolerance by SCIT, through the increase of Tregs, seems to depend on the periodical exposure to the allergen, at least during the early steady state.

Immunological characterization of onion (Allium cepa) allergy.

INTRODUCTION: Onion (Allium cepa) handling can induce contact dermatitis, rhinoconjunctivitis and asthma. However, only sporadic reports exist on allergic reactions to onion consumption. AIM: We describe herein a case of a 35-year-old man who had an episode of anaphylaxis following cooked onion ingestion. We evaluated onion-specific IgE, the possible cross-reactivity between onion and peach and lymphocyte proliferation in response to onion. MATERIAL AND METHODS: Specific IgE was evaluated using two techniques: skin test and ImmunoCAP technology. Cross-reactivity between onion and peach was evaluated by IgE-ELISA inhibition test. As for lymphocyte proliferation, blood mononuclear cells were stained with CFSE dye and cultured with an in-house onion extract. Proliferation and phenotype was assessed by flow-cytometry. RESULTS: The skin test and ImmunoCAP confirmed the IgE-dependent response towards onion. The incubation of the patient serum with increasing concentrations of the peach extract reduced only scarcely (~30%) onion-specific IgE. Interestingly, B cells but not T cells showed proliferation in response to onion extract. CONCLUSIONS: In conclusion, our report shows that cooked onion can induce severe allergic reactions, suggesting the presence of thermostable components. Moreover, we applied for the first time a B-cell-based approach to the diagnosis of food allergy. This latter approach might also be applied to other allergic conditions.

Efficacy and safety of allergen immunotherapy in patients with allergy to molds: A systematic review.

BACKGROUND: Allergen immunotherapy (AIT) with mould extracts has been performed for many years but the final demonstration of its clinical efficacy is still missing, due to the small number of studies and their inconsistent results. OBJECTIVE: To systematically review efficacy and safety of AIT for the treatment of respiratory allergies to moulds. DESIGN: The primary outcomes were safety and reduction of symptoms (Symptom Score, SS) and medication use (Medication Score, MS) in patients treated with AIT compared to controls. The strength of the evidence was graded based on the risk of bias, consistency and magnitude of effect, according to the GRADE Working Group's guide. DATA SOURCES: Medline, Web of Science and the Cochrane Library (through September 2017) supplemented with manual searches of reference lists. ELIGIBILITY CRITERIA: Randomized studies of intervention comparing AIT to placebo/pharmacotherapy. Studies not reporting on our outcome of interest or without a control population were excluded. RESULTS: Nine studies (168 children, 99 adults; median sample size, 27) met the inclusion criteria. The risk of bias was moderate-to-high in all but one study. Low strength evidence supports the assumption that AIT is effective in reducing symptoms and medication use, with only four of nine studies reporting higher benefit of AIT vs. comparators. The highest benefit of AIT compared to pharmacotherapy/placebo was reported in studies with a longer follow-up (SMD for MS from -3.96 to -3.97 in favour of AIT) and low risk of bias (VAS for SS: 66.3 ± 13 in AIT group; 186.6 ± 39 in comparators; P < 0.05). No difference was reported with respect to study sample size, route of administration, age of participants. Generalised adverse reactions were reported in 12.5% of participants treated with sublingual immunotherapy, and 37.2% of participants treated with subcutaneous immunotherapy. CONCLUSIONS: Low strength evidence suggests that mould AIT is efficacious for the treatment of respiratory allergies. High-quality studies with an adequate sample size are needed.

Rapid desensitization for brentuximab vedotin (Adceteris®) allergy: a case report.

BACKGROUND: Brentuximab vedotin (BV) is an antibody-drug conjugate formed by an anti-CD30 chimeric IgG1 conjugated with monomethyl-auristatin-E. BV targets the CD30+ cells, which characterize Hodgkin lymphoma as well as anaplastic large cell lymphoma. Once bound to the CD30+ cells BV exerts its cytotoxic effect via the monomethyl-auristatin-E moiety. So far, accounts on immediate adverse reactions to BV remain anecdotal. Moreover, few reports exist on desensitization for BV. CASE PRESENTATION: A 20-year old male patient was diagnosed with Hodgkin lymphoma in July 2014. The first line treatment with adriblastine, bleomicine, vinblastine and dacarbazine lead to a partial remission. Thus, a treatment with BV was started. However, during the second BV infusion, he developed generalized urticaria and dyspnea. In order not to discontinue the treatment with BV, we performed a thorough allergological workup and designed a 12-step rapid desensitization protocol. Overall the desensitization procedure was well tolerated and no major adverse reactions occurred. CONCLUSION: Rapid desensitization is a suitable and safe option in the case of BV allergy and prevents the BV treatment withdrawal.

A 13-year real-life study on efficacy, safety and biological effects of Vespula venom immunotherapy.

BACKGROUND: Hymenoptera venom immunotherapy (VIT) is a clinically effective treatment. However, little is known about its long-term clinical efficacy and biological effects. Several mechanisms have been proposed to account for VIT efficacy, including reduction of specific IgE and induction of allergen-specific IgG4, but the overall picture remains elusive. We investigated Vespula VIT clinical efficacy up to 8 years after discontinuation and the kinetics of Vespula-specific IgE and IgG4. Out of 686 consecutive patients we retrospectively selected and analysed a series of 23 patients with Vespula allergy that underwent a 5-year IT course, followed by a prolonged follow-up. METHODS: Clinical efficacy of VIT was assessed as number and severity of reactions to Vespula re-stinging events. The presence of Vespula-specific IgE and IgG4 was also monitored over time. RESULTS: During the VIT treatment, patients were protected, reporting no reactions or mild reactions in occasion of re-stinging events. This protection was entirely maintained during the follow-up, up to 8 years. Skin reactivity (reflecting mast cell-bound Vespula-specific IgE) and circulating Vespula-specific IgE levels declined substantially during VIT. Notably, this reduction was maintained over time during the follow-up. Moreover, all the patients were analysed for IgG4. A robust induction of Vespula-specific IgG4 was observed during the VIT course, with a substantial decline during the follow-up. CONCLUSIONS: We conclude that Vespula VIT is a clinically effective treatment, which induces long-term protection after discontinuation. The reduction of specific IgE, assessed by skin tests and RAST, closely matches the VIT- induced protection, while the IgG4 induction seems not to be associated with VIT clinical efficacy in the long term.

Conditional ablation of NKp46+ cells using a novel Ncr1(greenCre) mouse strain: NK cells are essential for protection against pulmonary B16 metastases.

To study gene functions specifically in NKp46+ cells we developed novel Cre mice allowing for conditional gene targeting in cells expressing Ncr1 (encoding NKp46). We generated transgenic Ncr1(greenCre) mice carrying an EGFPcre fusion under the control of a proximal Ncr1 promoter that faithfully directed EGFPcre expression to NKp46+ cells from lymphoid and nonlymphoid tissues. This approach allowed for direct detection of Cre-expressing NKp46+ cells via their GFP signature by flow cytometry and histology. Cre was functional as evidenced by the NKp46+ cell-specific expression of RFP in Ncr1(greenCre) Rosa-dtRFP reporter mice. We generated Ncr1(greenCre) Il2rg(fl/fl) mice that lack NKp46+ cells in an otherwise intact hematopoietic environment. Il2rg encodes the common gamma chain (γc ), which is an essential receptor subunit for cytokines (IL-2, -4, -7, -9, -15, and -21) that stimulate lymphocyte development and function. In Ncr1(greenCre) Il2rg(fl/fl) mice, NK cells are severely reduced and the few remaining NKp46+ cells escaping γc deletion failed to express GFP. Using this new NK-cell-deficient model, we demonstrate that the homeostasis of NKp46+ cells from all tissues (including the recently described intraepithelial ILC1 subset) requires Il2rg. Finally, Ncr1(greenCre) Il2rg(fl/fl) mice are unable to reject B16 lung metastases demonstrating the essential role of NKp46+ cells in antimelanoma immune responses.

The high-affinity human IgG receptor FcγRI (CD64) promotes IgG-mediated inflammation, anaphylaxis, and antitumor immunotherapy.

Receptors for the Fc portion of IgG (FcγRs) are mandatory for the induction of various IgG-dependent models of autoimmunity, inflammation, anaphylaxis, and cancer immunotherapy. A few FcγRs have the ability to bind monomeric IgG: high-affinity mouse mFcγRI, mFcγRIV, and human hFcγRI. All others bind IgG only when aggregated in complexes or bound to cells or surfaces: low-affinity mouse mFcγRIIB and mFcγRIII and human hFcγRIIA/B/C and hFcγRIIIA/B. Although it has been proposed that high-affinity FcγRs are occupied by circulating IgG, multiple roles for mFcγRI and mFcγRIV have been reported in vivo. However, the potential roles of hFcγRI that is expressed on monocytes, macrophages, and neutrophils have not been reported. In the present study, we therefore investigated the role of hFcγRI in antibody-mediated models of disease and therapy by generating hFcγRI-transgenic mice deficient for multiple endogenous FcRs. hFcγRI was sufficient to trigger autoimmune arthritis and thrombocytopenia, immune complex-induced airway inflammation, and active and passive systemic anaphylaxis. We found monocyte/macrophages to be responsible for thrombocytopenia, neutrophils to be responsible for systemic anaphylaxis, and both cell types to be responsible for arthritis induction. Finally, hFcγRI was capable of mediating antibody-induced immunotherapy of metastatic melanoma. Our results unravel novel capabilities of human FcγRI that confirm the role of high-affinity IgG receptors in vivo.

Neutrophils mediate antibody-induced antitumor effects in mice.

Tumor engraftment followed by monoclonal antibody (mAb) therapy targeting tumor antigens represents a gold standard for assessing the efficiency of mAbs to eliminate tumor cells. Mouse models have demonstrated that receptors for the Fc portion of immunoglobulin G (FcγRs) are critical determinants of mAb therapeutic efficacy, but the FcγR-expressing cell populations responsible remain elusive. We show that neutrophils are responsible for mAb-induced therapy of both subcutaneous syngeneic melanoma and human breast cancer xenografts. mAb-induced tumor reduction, abolished in neutropenic mice, could be restored in FcγR-deficient hosts upon transfer of FcγR+ neutrophils or upon human FcγRIIA/CD32A transgenic expression. Finally, conditional knockout mice unable to perform FcγR-mediated activation and phagocytosis specifically in neutrophils were resistant to mAb-induced therapy. Our work suggests that neutrophils are necessary and sufficient for mAb-induced therapy of subcutaneous tumors, and represent a new and critical focal point for optimizing mAb-induced immunotherapies that will impact on human cancer treatment.