Evaluating primary end points in peanut immunotherapy clinical trials.

Food immunotherapy has been the focus of several allergy research initiatives over the last decade. Although many questions remain unanswered, the evidence suggests that this treatment might be available in the near future outside clinical trials. Additionally, pharmaceutical companies, in light of promising early-stage results, have shown interest in developing commercially available products, thus increasing the likelihood that new immunotherapy treatments will be introduced, especially for peanut allergy. Given this optimistic scenario and given the prospect of rigorously developed products for peanut allergy treatment, each allergist will need to understand the specificities of these treatments and their expected efficacy and adverse event profiles. Thus it is imperative that allergists understand the differences in efficacy between the different management options, as well as how the end points are measured in the relevant literature. However, given the significant heterogeneity detected among food immunotherapy trials, this task might not be as straightforward as desired. This article aims to dissect how primary efficacy end points are defined and assessed to facilitate understanding of the design of these trials and the potential effect that this variation might have on the reported outcomes.

Encapsulated Limonene: A Pleasant Lemon-Like Aroma with Promising Application in the Agri-Food Industry. A Review.

Limonene, mainly found as a major component in Citrus spp., has been proven to possess a valuable potential as sustainable replacement to synthetic pesticides and food preservatives. This review intends to give a clear overview of the principal emerging applications of limonene in the agri-food industry as antimicrobial, herbicidal and antioxidant agent. To successfully use limonene in a greener agri-food industry, its preservation had become a top concern for manufacturers. In order to elucidate the most efficient and sustainable manner to encapsulate limonene, the different techniques and materials tested up to the present are also reviewed. In general, encapsulation conserves and protects limonene from outside aggressions, but also allows its controlled release as well as enhances its low water solubility, which can be critical for the discussed applications. Other parameters such as scalability, low cost and availability of equipment will need to be taken into account. Further efforts would likely be oriented to the elucidation of encapsulating sustainable systems obtained by cost-efficient elaboration processes, which can deliver effective concentrations of limonene without affecting crops and food products.

Association between Non-Competitive Physical Exercise and Menstrual Disorders.

Menstrual disorders are highly prevalent and generate discomfort, anxiety, and more gynecological visits. There has been an increase in the practice of physical exercise among the general population. This study determined the association between physical exercise and menstrual disorders. An observational analytical study was conducted during 2016 in women of reproductive age from southeast Spain. Information was collected on sociodemographic, gynecological, and nutritional status variables, and the International Physical Activity Questionnaire (IPAQ) was used to gather data on physical exercise. Quantitative/qualitative variables were compared using the non- parametric Mann-Whitney U test and categorical variables with the chi-square (χ2) or Fisher's exact test, followed by multivariate logistic regression analysis. The study included 122 women; physical exercise was practiced by 50%; menstrual disorders were reported by 53.28 %. The practice of physical exercise, h/week of physical exercise, body type, level of physical exercise, and marital status were associated with the presence of menstrual cycle disorders (p˂0.05). This association persisted (p=0.042) after adjustment of the analysis for impaired nutritional status, medication consumption, the presence of disease, age, marital status, age at menarche, and number of children. A high physical activity not related to the practice of sport is associated with menstrual disorders.

Phytotoxic Effects of Commercial Eucalyptus citriodora, Lavandula angustifolia, and Pinus sylvestris Essential Oils on Weeds, Crops, and Invasive Species.

BACKGROUND: essential oils are well known for their pharmacological effectiveness as well as their repellent, insecticide, and herbicide activities. The emergence of resistant weeds, due to the overuse of synthetic herbicides, makes it necessary to find natural alternatives for weed control. The aim of this study was to evaluate the phytotoxic effects of Eucalyptus citriodora, Lavandula angustifolia, and Pinus sylvestris, three common commercial essential oils, on weeds (Portulaca oleracea, Lolium multiflorum, and Echinochloa crus-galli), food crops (tomato and cucumber), and the invasive species Nicotiana glauca. Methods: to determine herbicidal effects, essential oils were tested at different concentrations (0.125-1µL/mL). The index of germination and seedling length data were recorded over 14 days. RESULTS: the in vitro assays showed that L. angustifolia with linalool (38.7 ± 0.1%), 1,8-cineole (26.5 ± 0.1%), and camphor (14.2 ± 0.1%) as the main compounds showed the most phytotoxic effects affecting seed germination in weeds and tomato, and the aforementioned invasive species. L. multiflorum was the most sensitive weed, particularly to lavender essential oil, which decreased the growth of its hypocotyl and radicle by 87.8% and 76.7%, respectively, at a dose of 1 µL/mL. Cucumber was the most resistant food crop, with no significant reduction observed in seed germination and hypocotyl growth with E. citriodora and L. angustifolia essential oils. CONCLUSIONS: lavender essential oil represents a promising candidate for the development of effective and safe herbicides in the management of L. multiflorum affecting cucumber crops.

Prospective assessment of diagnostic tests for pediatric penicillin allergy: From clinical history to challenge tests.

BACKGROUND: Diagnostic guidelines for penicillin allergy in children recommend cumbersome protocols based partially on data from adults, which may be suboptimal for pediatric use. OBJECTIVE: To assess the accuracy of tools for diagnosis of penicillin allergy in children. METHODS: A prospective, multicenter study was conducted in children with reported adverse events related to penicillin, excluding severe reactions. All patients underwent a uniform diagnostic protocol that consisted of clinical history, skin tests, serum specific IgE (sIgE), and, regardless of these results, drug provocation tests (DPTs). RESULTS: A total of 732 children (mean age, 5.5 years; 51.2% males) completed the allergy workup, including DPTs. Amoxicillin triggered 96.9% of all reactions. None of the patients with an immediate index reaction (IR) developed a reaction on DPT. Penicillin allergy was confirmed in 35 children (4.8%): 6 immediate reactions (17%) and 29 nonimmediate reactions (83%) on the DPT. No severe reactions were recorded. The allergist diagnosis based on the clinical history was not associated with the DPT final outcome. In 30 of 33 allergic patients (91%), the results of all skin tests and sIgE tests were negative. A logistic regression model identified the following to be associated with penicillin allergy: a family history of drug allergy (odds ratio [OR], 3.03; 95% confidence interval [CI], 1.33-6.89; P = .008), an IR lasting more than 3 days vs 24 hours or less (OR, 8.96; 95% CI, 2.01-39.86; P = .004), and an IR treated with corticosteroids (OR, 2.68; 95% CI, 1.30-5.54; P = .007). CONCLUSION: Conventional predictors of allergy to penicillin performed weakly. The authors propose straightforward penicillin provocation testing in controlled, experienced centers for the diagnosis of nonsevere penicillin allergy in children.

Efficacy and safety of high-dose rush oral immunotherapy in persistent egg allergic children: A randomized clinical trial.

BACKGROUND: Egg oral immunotherapy is effective but time consuming. OBJECTIVE: To assess the efficacy and safety of egg rush oral immunotherapy (ROIT) with a targeted dose equivalent to a raw egg white. METHODS: Thirty-three persistent egg allergic children confirmed by double-blind, placebo-controlled food challenge (DBPCFC) were randomized to receive egg ROIT immediately after randomization (ROIT1 group), or to continue an egg avoidance diet for 5 months after randomization (control group [CG]). A 5-day build-up phase starting with the highest single tolerated dose at baseline DBPCFC was scheduled and several doses administered daily until achieving a dose of approximately 2,808 mg of egg white protein. In the maintenance phase, patients ate an undercooked egg every 48 hours for 5 months. The CG participants who failed the DBPCFC at 5 months began active treatment. Children from the ROIT1 group plus children from the CG who failed a second DBPCFC at 5 months and then received egg ROIT were randomized to the ROIT2 group. Adverse events (AEs) and immune marker evolution were recorded. RESULTS: A total of 17 (89%) of 19 children in the ROIT1 group and no CG patients were desensitized at 5 months (P < .001). A total of 31 (97%) of the 32 children in the ROIT2 group completed the build-up phase in a median of 3 days (range, 1-14 days), and 30 (94%) of 32 maintained desensitization at 5 months. From baseline to 5 months of treatment, skin prick test, specific IgE, and specific IgE/IgG4 ratio to egg fractions significantly decreased, whereas specific IgG4 increased. During the build-up phase, AEs occurred in 69% of patients (50% had ≤2 AEs) and 31% of doses (2% severe, 55% gastrointestinal). Lower threshold dose in the DBPCFC and higher egg white and ovalbumin specific IgE levels at baseline revealed an association with a higher rate of AEs. CONCLUSION: The proposed 5-day egg ROIT desensitized 94% of the allergic patients, with most AEs being mild or moderate.

Exercise-induced bronchospasm diagnosis in children. Utility of combined lung function tests.

BACKGROUND: The diagnosis of exercise-induced asthma or bronchospasm (EIB) is a complex dare in daily clinical practice. The consensus is that if bronchial hyper-responsiveness (BHR) is demonstrated in a patient with symptoms consistent with EIB, then that patient can be diagnosed with exercise-induced bronchospasm. The aim of this study was to determine which BHR test is the most efficient to diagnose EIB. METHODS: Children under 16, without previous asthma diagnosis, or with stable asthma, complaining of asthma-like symptoms triggered by exercise were included. Bronchodilator, methacholine, mannitol, and exercise tests were performed on all patients, following established protocols. The performance of single and combined tests was determined. RESULTS: Of 46 patients (median age: 12 yr, ranged 8-16 y.o.) were recruited, 30 (70%) previously diagnosed of asthma. BHR was detected in 93.47% of the children. The exercise challenge test detected BHR in 11 of 46 (23.90%) patients, bronchodilator test in 10 of 46 (21.70%), mannitol in 36 of 45 (80%) and methacholine in 41 of 45 (91.11%). The total number of patients with BHR was detected using a combination of the methacholine and mannitol tests. A combination of the methacholine test performed first, followed by the mannitol test, was able to diagnose BHR in 100% of children with lower number of tests (n = 45) than if the order was reversed (n = 50). CONCLUSIONS: Methacholine and mannitol tests detect BHR in most children with suspected EIB. Bronchodilator and exercise tests show a low positivity rate. A combination of the methacholine test, followed by the mannitol test, gives the highest return to identify BHR in children for the diagnosis of EIB.

Anaphylaxis induced by a drug containing lysozyme and papain: influence of papain on the IgE response.

BACKGROUND: This paper reports the case of an egg-allergic pediatric patient who, once desensitized to egg following a successful rush oral immunotherapy protocol, could also tolerate Lizipaina®, a drug containing lysozyme (LYS) and papain, which had previously caused him a severe allergic reaction. Because the LYS amount that elicited the anaphylactic reaction (5 mg) was much lower than that tolerated during a double-blind placebo-controlled food challenge (corresponding to approximately 60 mg of LYS), the possibility that the presence of papain could increase the allergenic potential of LYS was investigated. METHODS: Lizipaina, LYS and LYS hydrolyzed with papain were analyzed by SDS-PAGE under reducing and nonreducing conditions, and Western blotting of sera from egg-allergic patients was performed in order to detect IgE-binding fragments. Finally, sequence identification of the IgE-reactive bands was carried out by MALDI-TOF/TOF. RESULTS: The SDS-PAGE pattern of LYS treated with papain under nonreducing conditions showed the presence of intact LYS that partially disappeared following reduction with ß-mercaptoethanol, releasing IgE-reactive fragments as determined by Western blotting. MALDI-TOF/TOF revealed that papain degraded LYS, giving rise to three IgE-binding fragments: LYS (22-129), LYS (34-96) and LYS (62-128) that likely remained linked through the disulfide bonds present in the LYS molecule. CONCLUSION: The combined administration of LYS with proteolytic enzymes such as papain may have developed a severe allergic reaction in the patient studied, underlining the importance of considering all the components and their interactions when drugs are to be consumed by allergic persons.

Dehydrated egg white: an allergen source for improving efficacy and safety in the diagnosis and treatment for egg allergy.

BACKGROUND: Raw and cooked eggs are used as allergens in oral food challenge (OFC). Raw egg is the best option, as it keeps proteins intact and retains their allergenicity, albeit microbiologically safe manipulation is difficult. Therefore, the use of dehydrated egg white (DEW) could improve the efficacy and safety profile of OFC. The aim of the study was to compare the allergenicity of DEW, a product that undergoes a double heat treatment (pasteurization and drying), with that of raw egg white (REW) and determine the efficacy of DEW in the diagnosis of egg allergy. METHODS: We conducted a prospective study of 40 egg-allergic patients who visited our outpatient clinic. Each patient underwent OFC with DEW and REW to determine the correlation between the tests. DEW and REW extracts were analyzed using SDS-PAGE. We compared the allergenicity of both extracts using IgE immunoblotting with a serum pool from patients with positive OFC results. RESULTS: Ten patients (25%) had positive OFC results with both DEW and REW, and the doses that triggered an allergic reaction in each patient were similar (p > 0.05). All 30 patients (75%) with a negative OFC result with DEW also had negative OFC results with REW. SDS-PAGE and IgE immunoblotting revealed that the protein composition and IgE-binding capacity of both extracts were virtually identical. CONCLUSIONS: This is the first time that it is shown that the allergenicity of commercially available DEW is equivalent to raw egg whites. In vivo and in vitro tests showed that processing of DEW does not affect the allergenicity of egg proteins. DEW is an effective and microbiologically safer source of allergen for the diagnosis of egg allergy. Furthermore, DEW can be used in egg oral immunotherapy.

Analysis of comorbidities and therapeutic approach for allergic rhinitis in a pediatric population in Spain.

BACKGROUND: Allergic rhinitis (AR) is the most common chronic disease in children. The main objective of this study was to analyze the comorbidities and therapeutic approaches for AR in a Spanish pediatric population. METHODS: Children aged 6 to 12 years with AR were included in an observational, cross-sectional, multicenter study. RESULTS: 1,275 children were recruited from 271 centers. AR was intermittent in 59.5% of cases, persistent in 40.5%, seasonal in 60.7%, and perennial in 39.3% of patients. The most frequent comorbidities were conjunctivitis (53.6%), asthma (49.5%), atopic dermatitis (40%), rhinosinusitis(26.1%), otitis media (23.8%), and adenoid hypertrophy (17.3%). Overall, patients with persistent, moderate or severe, AR were more likely to present comobidities, except for food allergy and urticaria. The most common drugs used for treatment of AR were oral antihistamines(76%), nasal corticosteroids(49%) and a combination of both (45%). Antihistamines and nasal corticosteroids were used on demand (<18 days) in 38 and 41% of patients, respectively; for 18-30 days in 22 and 27%; for 1-3 months in 31 and 29%; and for more than 3 months in 8 and 3%, respectively. Eye drops were used in 32% and specific immunotherapy in 21% of patients. CONCLUSION: Comorbidities are frequent in children with AR, supporting the notion of allergy as a systemic disease. Severity and duration of AR were significantly associated with presence of most of comorbidities. The most common drugs used for AR treatment were oral antihistamines, followed by nasal corticosteroids and a combination of both used on demand.

Allergy to goat's and sheep's milk in a population of cow's milk-allergic children treated with oral immunotherapy.

BACKGROUND: Cow's milk oral immunotherapy (CMOIT) is a recognized treatment for persistent cow's milk (CM) allergy. However, further data are necessary on tolerance to milk from other mammals. OBJECTIVE: To describe the clinical and immunologic features of goat's and sheep's milk (GSM) allergy in patients who tolerated CM after CMOIT. METHODS: Fifty-eight CM-allergic patients who successfully underwent CMOIT in our department were evaluated using skin prick test (SPT), specific immunoglobulin (Ig) E determination, enzyme-linked immunoassay (ELISA), and controlled oral challenge to assess allergy to GSM. Statistical analysis was carried out to identify markers of allergy to GSM. RESULTS: Fifteen of 58 (25.9%) patients were allergic to either goat's or sheep's milk or to both, as confirmed by a controlled positive oral challenge. Forty-seven percent of all positive oral challenges were classified as anaphylactic reactions. Specific IgE to CM casein, goat's whole milk, and sheep's whole milk was 13.2, 18.0, and 21.4 kU(A)/l in the group of GSM-allergic patients and 6.6, 6.5, and 6.5 kU(A) /l in the GSM-non-allergic patients (p < 0.05). Decision-making cut-off points based on sIgE for diagnosing symptomatic GSM allergy could not be determined. ELISA inhibition assays showed limited cross-reactivity (up to 77.2%) between CM casein and GSM casein in the group of GSM-allergic patients in contrast with almost 100% in GSM-not-allergic patients. CONCLUSION: We found a high prevalence (26%) of allergy to GSM in our population of CM-allergic children treated with oral immunotherapy. Therefore, tolerance to GSM should be assessed in order to provide accurate nutritional advice and minimize life-threatening accidental intake. Specific IgE to CM casein, goat's and sheep's whole milk is a good marker of this allergy. Although CM oral immunotherapy is a specific treatment for CM allergy, it may not be effective against allergy to the milk of other mammals.

Peanut allergy: Clinical and immunologic differences among patients from 3 different geographic regions.

BACKGROUND: Peanut allergy affects persons from various geographic regions where populations are exposed to different dietary habits and environmental pollens. OBJECTIVE: We sought to describe the clinical and immunologic characteristics of patients with peanut allergy from 3 countries (Spain, the United States, and Sweden) using a molecular component diagnostic approach. METHODS: Patients with peanut allergy from Madrid (Spain, n = 50), New York (United States, n = 30), Gothenburg, and Stockholm (both Sweden, n = 35) were enrolled. Clinical data were obtained either from a specific questionnaire or gathered from chart reviews. IgE antibodies to peanut extract and the peanut allergens rAra h 1, 2, 3, 8 and 9, as well as to cross-reactive birch (rBet v 1) and grass (rPhl p 1, 5, 7, and 12) pollen allergens, were analyzed. RESULTS: American patients frequently had IgE antibodies to rAra h 1 to 3 (56.7% to 90.0%) and often presented with severe symptoms. Spanish patients recognized these 3 recombinant peanut allergens less frequently (16.0% to 42.0%), were more often sensitized to the lipid transfer protein rAra h 9 (60.0%), and typically had peanut allergy after becoming allergic to other plant-derived foods. Swedish patients detected rAra h 1 to 3 more frequently than Spanish patients (37.1% to 74.3%) and had the highest sensitization rate to the Bet v 1 homologue rAra h 8 (65.7%), as well as to rBet v 1 (82.9%). Spanish and Swedish patients became allergic to peanut at 2 years or later, whereas the American children became allergic around 1 year of age. CONCLUSIONS: Peanut allergy has different clinical and immunologic patterns in different areas of the world. Allergen component diagnostics might help us to better understand this complex entity.

Healthy Zerumbone: From Natural Sources to Strategies to Improve Its Bioavailability and Oral Administration.

Zerumbone is a multifunctional compound with antimicrobial, antitumor, hyperalgesic, antioxidant and anti-inflammatory applications, and constitutes a point molecule for the future synthesis of derivatives with improved efficiency. This monocyclic sesquiterpenoid is found in high content in wild ginger (Zingiber zerumbet Smith), a perennial herb with economic importance as an ornamental as well as a medicinal plant. The presence of zerumbone is a distinctive feature that allows identification and differentiation from other species, not only in Zingiber, but also in Curcuma, Alpinia, Boesenbergia, Ethlingera and Ammomum spp., as well as related families (Costaceaee). To successfully use zerumbone in areas such as medicine, food and agriculture, further research on improving its low solubility and bioavailability, as well as its preservation, is a major current priority. In addition, despite its promising pharmacological activities, preclinical and clinical studies are required to demonstrate and evaluate the in vivo efficacy of zerumbone.

On the Move-Sensitive Fluorescent Aptassay on Board Catalytic Micromotors for the Determination of Interleukin-6 in Ultra-Low Serum Volumes for Neonatal Sepsis Diagnostics.

A graphene oxide/nickel/platinum nanoparticle micromotor (MM)-based fluorescent aptassay is proposed to determine interleukin-6 (IL-6) in serum samples from low-birth-weight infants (gestational age of less than 32 weeks and birthweight below 1000 g) with sepsis suspicion. In this kind of patients, IL-6 has demonstrated good sensitivity and specificity for the diagnosis of sepsis, both for early and late onset sepsis. The approach was based on the adsorption of the aptamer for IL-6 tagged with 6-FAM as a fluorescent label (AptIL-6, λem = 520 nm) on the graphene oxide external layer (MMGO-AptIL-6) inducing fluorescence quenching (OFF state) and a subsequent on-the-move affinity recognition of IL-6 from AptIL-6 (IL-6-AptIL-6 complex) recovering the fluorescence (ON state). An aptamer against IL-6 was selected and developed by the systematic evolution of ligands by exponential enrichment technology. This approach displayed a suitable linear range of 0.07-1000 pg mL-1 (r = 0.995) covering the cut-off and clinical practice levels, allowing direct determination without any dilution and simplifying the analysis as well as exhibiting an excellent sensitivity (LOD = 0.02 pg mL-1) in ultralow volumes of diagnostic clinical samples (2 µL). A high agreement between IL-6 levels obtained from our MM-based approach and the method used by the Hospital was obtained (relative error < 3%). The MM-based aptassay is competitive in comparison with that of the Hospital, in terms of a significant reduction of the sample volume (15 times less) and enhanced sensitivity, employing similar analysis times. These results position MM technology with enough potential to achieve high sensitivities in low sample volumes, opening new avenues in diagnosis based on low sample volumes.

Association of miR-21 and miR-335 to microsatellite instability and prognosis in stage III colorectal cancer.

BACKGROUND: MicroRNAs (miRs) are frequently altered in colorectal cancer (CRC) and can be used as prognostic factors. OBJECTIVE: To confirm in stage III CRC patients a reported miR signature that was associated to the presence of metastatic disease. To correlate miR expression with microsatellite instability (MSI) and mutations in RAS and BRAF. METHODS: miR-21, miR-135a, miR-206, miR-335 and miR-Let-7a expression was analyzed by RT-qPCR in 150 patients out of the 329 patients used to analyze MSI and RAS and BRAF mutations. Association with disease free survival (DFS) and overall survival (OS) was analyzed. Data was confirmed by a multivariate analysis. RESULTS: MiR-21 high expression (p= 0.034) and miR-335 low expression (p= 0.0061) were significantly associated with MSI-H. A positive trend (p= 0.0624) between miR-135a high expression and RAS mutations was found. Lower miR-21 expression levels are associated with DFS (HR = 2.654, 95% CI: 1.066-6.605, p= 0.036) and a trend with OS (HR = 2.419, 95% CI: 0.749-7.815, p= 0.140). MiR-21 high expression significantly improves DFS of the poor prognosis group (T4 or N2) (p= 0.03). CONCLUSIONS: Association of increased expression of miR-21 and better prognosis in the poor prognostic group may be of interest and could be explored in future prospective clinical trials.

Identification of IgE sequential epitopes of lentil (Len c 1) by means of peptide microarray immunoassay.

BACKGROUND: Lentils are often responsible for allergic reactions to legumes in Mediterranean children. Although the primary sequence of the major allergen Len c 1 is known, the location of the IgE-binding epitopes remains undefined. OBJECTIVE: We sought to identify IgE-binding epitopes of Len c 1 and relate epitope binding to clinical characteristics. METHODS: One hundred thirty-five peptides corresponding to the primary sequence of Len c 1 were probed with sera from 33 patients with lentil allergy and 15 nonatopic control subjects by means of microarray immunoassay. Lentil-specific IgE levels, skin prick test responses, and clinical reactions to lentil were determined. Epitopes were defined as overlapping signal above interslide and intraslide cutoffs and confirmed by using inhibition assays with a peptide from the respective region. Hierarchic clustering of microarray data was used to correlate binding patterns with clinical findings. RESULTS: The patients with lentil allergy specifically recognized IgE-binding epitopes located in the C-terminal region between peptides 107 and 135. Inhibition experiments confirmed the specificity of IgE binding in this region, identifying different epitopes. Linkage of cluster results with clinical data and lentil-specific IgE levels displayed a positive correlation between lentil-specific IgE levels, epitope recognition, and respiratory symptoms. Modeling based on the 3-dimensional structure of a homologous soy vicilin suggests that the Len c 1 epitopes identified are exposed on the surface of the molecule. CONCLUSION: Several IgE-binding sequential epitopes of Len c 1 have been identified. Epitopes are located in the C-terminal region and are predicted to be exposed on the surface of the protein. Epitope diversity is positively correlated with IgE levels, pointing to a more polyclonal IgE response.

Greater epitope recognition of shrimp allergens by children than by adults suggests that shrimp sensitization decreases with age.

BACKGROUND: Shellfish allergy is a long-lasting disorder typically affecting adults. Despite its high prevalence, there is limited information about allergenic shrimp proteins and the epitopes implicated in such allergic reactions. OBJECTIVE: We sought to identify the IgE-binding epitopes of the 4 shrimp allergens and to characterize epitope recognition profiles of children and adults with shrimp allergy. METHODS: Fifty-three subjects, 34 children and 19 adults, were selected with immediate allergic reactions to shrimp, increased shrimp-specific serum IgE levels, and positive immunoblot binding to shrimp. Study subjects and 7 nonatopic control subjects were tested by means of peptide microarray for IgE binding with synthetic overlapping peptides spanning the sequences of Litopenaeus vannamei shrimp tropomyosin, arginine kinase (AK), myosin light chain (MLC), and sarcoplasmic calcium-binding protein (SCP). The Wilcoxon test was used to determine significant differences in z scores between patients and control subjects. RESULTS: The median shrimp IgE level was 4-fold higher in children than in adults (47 vs 12.5 kU(A)/L). The frequency of allergen recognition was higher in children (tropomyosin, 81% [94% for children and 61% for adults]; MLC, 57% [70% for children and 31% for adults]; AK, 51% [67% for children and 21% for adults]; and SCP, 45% [59% for children and 21% for adults]), whereas control subjects showed negligible binding. Seven IgE-binding regions were identified in tropomyosin by means of peptide microarray, confirming previously identified shrimp epitopes. In addition, 3 new epitopes were identified in tropomyosin (epitopes 1, 3, and 5b-c), 5 epitopes were identified in MLC, 3 epitopes were identified in SCP, and 7 epitopes were identified in AK. Interestingly, frequency of individual epitope recognition, as well as intensity of IgE binding, was significantly greater in children than in adults for all 4 proteins. CONCLUSIONS: Children with shrimp allergy have greater shrimp-specific IgE antibody levels and show more intense binding to shrimp peptides and greater epitope diversity than adults.

Continuous and Daily Oral Immunotherapy for Peanut Allergy: Results from a 2-Year Open-Label Follow-On Study.

BACKGROUND: The randomized, controlled PALISADE trial demonstrated the benefit of daily oral immunotherapy with Peanut (Arachis Hypogaea) allergen powder-dnfp (PTAH, formerly AR101) in peanut-allergic children and adolescents. OBJECTIVE: ARC004, the open-label follow-on study to PALISADE, used 5 dosing cohorts to explore PTAH treatment beyond 1 year and alternative dosing regimens in peanut-allergic individuals. METHODS: Active arm (PTAH-continuing) PALISADE participants who tolerated 300-mg peanut protein at the exit double-blind placebo-controlled food challenge and placebo arm (PTAH-naive) participants could enter ARC004. PTAH-continuing participants were assigned to receive daily (cohorts 1 and 3A) or non-daily (cohorts 2, 3B, and 3C) dosing regimens; PTAH-naive participants were built up to 300 mg/d PTAH, followed by maintenance dosing. At study completion, participants underwent an exit double-blind placebo-controlled food challenge with doses up to 2000 mg peanut protein. Data were assessed using descriptive statistics. RESULTS: Overall, 358 (87.5%) eligible participants (4-17 years) entered ARC004 (PTAH-continuing, n = 256; PTAH-naive, n = 102). Among PTAH-continuing participants, exposure-adjusted adverse event rates were 12.94 to 17.54/participant-year and 25.95 to 42.49/participant-year in daily and non-daily dosing cohorts, respectively; most participants (83%) experienced mild or moderate adverse events. Daily dosing cohorts appeared to have higher desensitization rates than non-daily dosing cohorts. Of all PTAH-continuing cohorts, cohort 3A had the longest daily dosing duration and the highest desensitization rates. Changes in immune markers with PTAH continuation demonstrated ongoing immunomodulation. Outcomes in PTAH-naive participants mirrored those of the PALISADE active arm. CONCLUSIONS: Continued daily PTAH treatment beyond 1 year showed sustained safety and efficacy. Ongoing immunomodulation was observed during the second year of treatment.

Sarcoplasmic calcium-binding protein is an EF-hand-type protein identified as a new shrimp allergen.

BACKGROUND: Shellfish allergy is a long-lasting disorder usually persisting throughout life. Despite its high prevalence, there is limited information about allergenic shrimp proteins. OBJECTIVE: Characterization of shrimp allergens. METHODS: Fifty-two adults and children with a history of immediate allergic reactions to shrimp and elevated serum IgE to shrimp were selected for this study. Tryptic digests from a 20-kd IgE-binding protein were analyzed by LC-MS/MS, identifying the protein as a sarcoplasmic-calcium-binding protein. cDNA encoding sarcoplasmic calcium-binding protein (SCP) from a shrimp cDNA library (Litopenaeus vannamei) was amplified by PCR, cloned into an expression vector, and sequenced. Recombinant SCP was tested with patients' sera. ELISA inhibition experiments determined the fraction of total shrimp IgE recognizing SCP. A functional assay with a rat basophilic leukemia cell line was used to determine the capacity for mediator release induced by SCP. RESULTS: Immunoblotting demonstrated IgE binding by 31 of 52 (59.6%) of the sera to a 20-kd shrimp protein. The protein was identified as a SCP. Amplified cDNA encoding SCP was isolated and sequenced. Open reading frame translation provided the complete amino acid sequence of shrimp SCP. Recombinant SCP was recognized by serum IgE from 20 of 52 (38.4%) subjects, of whom 17 of 20 (85%) were children. ELISA inhibition of pooled sera IgE reactivity to BS extract using recombinant SCP was significant (as high as 79%). For some subjects, mediator release induced by recombinant SCP was higher than that induced by recombinant tropomyosin. CONCLUSION: We have identified and cloned a new shrimp allergen, Lit v 4.0101, an SCP, which appears to be of particular importance in the pediatric population.