[The impact of today's environment on allergies: can we take action?] / Incidence de l'environnement actuel sur les allergies : peut-on agir ?

Allergic diseases have risen sharply in recent decades. After some epidemiological data, we take a look at the various hypotheses explaining this allergy "epidemic". Changes in our environment, such as pollution, are a source of climate change and an increase in allergic diseases through inflammation of epithelial barriers. Allergy prevention, a public health emergency, relies on environmental actions at both individual and collective levels.

Extracellular vesicles of the probiotic bacteria E. coli O83 activate innate immunity and prevent allergy in mice.

BACKGROUND: E. coli O83 (Colinfant Newborn) is a Gram-negative (G-) probiotic bacterium used in the clinic. When administered orally, it reduces allergic sensitisation but not allergic asthma. Intranasal administration offers a non-invasive and convenient delivery method. This route bypasses the gastrointestinal tract and provides direct access to the airways, which are the target of asthma prevention. G- bacteria such as E. coli O83 release outer membrane vesicles (OMVs) to communicate with the environment. Here we investigate whether intranasally administered E. coli O83 OMVs (EcO83-OMVs) can reduce allergic airway inflammation in mice. METHODS: EcO83-OMVs were isolated by ultracentrifugation and characterised their number, morphology (shape and size), composition (proteins and lipopolysaccharide; LPS), recognition by innate receptors (using transfected HEK293 cells) and immunomodulatory potential (in naïve splenocytes and bone marrow-derived dendritic cells; BMDCs). Their allergy-preventive effect was investigated in a mouse model of ovalbumin-induced allergic airway inflammation. RESULTS: EcO83-OMVs are spherical nanoparticles with a size of about 110 nm. They contain LPS and protein cargo. We identified a total of 1120 proteins, 136 of which were enriched in OMVs compared to parent bacteria. Proteins from the flagellum dominated. OMVs activated the pattern recognition receptors TLR2/4/5 as well as NOD1 and NOD2. EcO83-OMVs induced the production of pro- and anti-inflammatory cytokines in splenocytes and BMDCs. Intranasal administration of EcO83-OMVs inhibited airway hyperresponsiveness, and decreased airway eosinophilia, Th2 cytokine production and mucus secretion. CONCLUSIONS: We demonstrate for the first time that intranasally administered OMVs from probiotic G- bacteria have an anti-allergic effect. Our study highlights the advantages of OMVs as a safe platform for the prophylactic treatment of allergy. Video Abstract.

Maternal fish oil and/or probiotics intervention: Allergic diseases in children up to two years old.

BACKGROUND: As n-3 long-chain polyunsaturated fatty acids and probiotics possess immunomodulatory properties, theoretically they could lower the risk of allergic diseases. But their effects remain controversial. We aimed to study the effects of fish oil and probiotics separately or in combination from early pregnancy onwards to lower the risk of allergic diseases in the infants. METHODS: In this double-blind trial, women (n = 439) in early pregnancies were randomized into four intervention groups: fish oil + placebo, probiotics + placebo, fish oil + probiotics, and placebo + placebo. Fish oil (1.9 g docosahexaenoic acid and 0.22 g eicosapentaenoic acid) and probiotic (Lacticaseibacillus rhamnosus HN001 and Bifidobacterium animalis ssp. lactis 420, 1010 colony-forming units each) supplements were provided for daily consumption from randomization up to 6 months postpartum. All analyses were adjusted with pet ownership. RESULTS: No difference between the infants in the four intervention groups were found regarding physician-diagnosed food allergy, atopic eczema, or atopy at the age of 12 or 24 months (all p > .05). The probiotic intervention was associated with lower odds of recurrent wheezing at 24 months (OR 0.39, 95% CI 0.18-0.84, p = .017), but not at 12 months. CONCLUSIONS: The use of fish oil and/or probiotics from early pregnancy onwards did not lower the odds of childhood allergic diseases or atopy, with the exception of the probiotic intervention which decreased the risk of recurrent wheezing when the infants were two years old. This suggests that the incidence of asthma could also decrease later in childhood and thus these outcomes need to be clarified in further investigations.

Full Breastfeeding and Allergic Diseases-Long-Term Protection or Rebound Effects?

A previous follow-up of the GINIplus study showed that breastfeeding could protect against early eczema. However, effects diminished in adolescence, possibly indicating a "rebound effect" in breastfed children after initial protection. We evaluated the role of early eczema until three years of age on allergies until young adulthood and assessed whether early eczema modifies the association between breastfeeding and allergies. Data from GINIplus until 20-years of age (N = 4058) were considered. Information on atopic eczema, asthma, and rhinitis was based on reported physician's diagnoses. Adjusted Odds Ratios (aOR) were modelled by using generalized estimating equations. Early eczema was associated with eczema (aORs = 3.2-14.4), asthma (aORs = 2.2-2.7), and rhinitis (aORs = 1.2-2.7) until young adulthood. For eczema, this association decreased with age (p-for-interaction = 0.002-0.006). Longitudinal models did not show associations between breastfeeding and the respective allergies from 5 to 20 years of age. Moreover, early eczema generally did not modify the association between milk feeding and allergies except for rhinitis in participants without family history of atopy. Early eczema strongly predicts allergies until young adulthood. While preventive effects of full breastfeeding on eczema in infants with family history of atopy does not persist until young adulthood, the hypothesis of a rebound effect after initial protection cannot be confirmed.

A Review on Maternal and Infant Microbiota and Their Implications for the Prevention and Treatment of Allergic Diseases.

Allergic diseases, which are closely related to the composition and metabolism of maternal and infant flora, are prevalent in infants worldwide. The mother's breast milk, intestinal, and vaginal flora directly or indirectly influence the development of the infant's immune system from pregnancy to lactation, and the compositional and functional alterations of maternal flora are associated with allergic diseases in infants. Meanwhile, the infant's own flora, represented by the intestinal flora, indicates and regulates the occurrence of allergic diseases and is altered with the intervention of allergic diseases. By searching and selecting relevant literature in PubMed from 2010 to 2023, the mechanisms of allergy development in infants and the links between maternal and infant flora and infant allergic diseases are reviewed, including the effects of flora composition and its consequences on infant metabolism. The critical role of maternal and infant flora in allergic diseases has provided a window for probiotics as a microbial therapy. Therefore, the uses and mechanisms by which probiotics, such as lactic acid bacteria, can help to improve the homeostasis of both the mother and the infant, and thereby treat allergies, are also described.

From Amish farm dust to bacterial lysates: The long and winding road to protection from allergic disease.

Allergic diseases typically begin in early life and can impose a heavy burden on children and their families. Effective preventive measures are currently unavailable but may be ushered in by studies on the "farm effect", the strong protection from asthma and allergy found in children born and raised on traditional farms. Two decades of epidemiologic and immunologic research have demonstrated that this protection is provided by early and intense exposure to farm-associated microbes that target primarily innate immune pathways. Farm exposure also promotes timely maturation of the gut microbiome, which mediates a proportion of the protection conferred by the farm effect. Current research seeks to identify allergy-protective compounds from traditional farm environments, but standardization and regulation of such substances will likely prove challenging. On the other hand, studies in mouse models show that administration of standardized, pharmacological-grade lysates of human airway bacteria abrogates allergic lung inflammation by acting on multiple innate immune targets, including the airway epithelium/IL-33/ILC2 axis and dendritic cells whose Myd88/Trif-dependent tolerogenic reprogramming is sufficient for asthma protection in adoptive transfer models. To the extent that these bacterial lysates mimic the protective effects of natural exposure to microbe-rich environments, these agents might provide an effective tool for prevention of allergic disease.

Quality of systematic reviews on timing of complementary feeding for early childhood allergy prevention.

BACKGROUND: Only rigorously prepared analyses can provide the highest level of evidence to inform decision-making. Several recent systematic reviews (SRs) examined the hypothesis that the early introduction of specific allergenic complementary foods (CFs) to infants may lead to a lower incidence of one or more allergic outcomes. However, the methodological rigour and quality of reporting of SRs in this area has not yet been systematically evaluated. METHODS: We comprehensively searched PubMed, Medline (Ovid), and Web of Science Core Collection on 13th January 2022, using a pre-specified and tested search syntax for SRs with RCT evidence on the early introduction of allergenic CFs as a means for allergy prevention in infants and children. We examined the quality and risk of bias (RoB) using AMSTAR-2 and ROBIS tools, examined adherence to the Preferred Reporting Items for SRs and Meta-Analyses (PRISMA), and checked whether certainty of the evidence was assessed. RESULTS: Twelve SRs were included. Application of both tools resulted in similar overall judgements in terms of direction and extent for nine of the 12 SRs. Nine SRs were found to be of critically low to low quality according to AMSTAR-2 and to be at high RoB according to ROBIS. One SR received a moderate quality rating (AMSTAR-2) and high RoB rating (ROBIS). However, for two SRs, judgements between AMSTAR-2 and ROBIS were at stark variance. Only two SRs fully adhered to the PRISMA checklist. Six SRs evaluated the certainty of the body of RCT evidence. Several SRs failed to consider unpublished studies either by an explicit a priori exclusion or by inadequate search strategies. CONCLUSIONS: Well-conducted SRs are important for decision-making and informing guideline development, the quality of their methodology should therefore be considered. The methodological rigour and the reporting quality of SRs on the timing of CF for allergy prevention must be improved. REGISTRATION: https://osf.io/7cs4b .

Erroneous detection of desensitization doses in the prevention of hypersensitivity reactions.

BACKGROUND: Desensitization protocols have empirically established their efficacy and safety in eliminating most of the hypersensitivity reactions to drugs and other allergens. Without such procedures, the offending drugs can otherwise be lethal, for some patients, when singularly administered at therapeutic doses. These binding events and the subsequent signaling cascades have been extensively modulated by different desensitization methods, without any clear explanation as to why it is necessary to use increasing allergen doses. PURPOSE: To use a novel theoretical approach in order to model the desensitization algorithms currently in practice, that seeks to shed light on the mechanism behind their clinical efficacy. METHOD: An approach using signal processing concepts is applied in this work to introduce aliasing as the erroneous detection of higher drug doses responsible for the efficacy of desensitization procedures. RESULTS: Available experimental data is modeled and correct predictions as to the efficacy of the drug treatment procedures are produced. CONCLUSIONS: Desensitization algorithms may benefit from using concepts from signal processing theory in order to avoid hypersensitivity reactions.

Prevention of Laboratory Animal Allergy and Impact of COVID-19 on Prevention Programs in the United States: A National Survey 10-Year Update.

OBJECTIVE: Laboratory animal allergy (LAA) is common and preventable. This study provides a 10-year update on LAA prevention programs in the United States and the effect of COVID-19 on prevention practices. METHODS: An electronic survey was e-mailed to designated institutional officials at laboratory animal facilities identified by the National Institutes of Health Office of Laboratory Animal Welfare. Results were compared with the prior survey. RESULTS: A total of 141 institutions employing 58,224 laboratory animal workers responded. Results were similar to the prior survey with wide variation in practices. Medical surveillance increased (58%-71%), but N95 respirator use decreased (17%-13%). As before, only 25% of institutions knew their LAA incidence and prevalence rates. COVID-19 had a small time-limited effect on personal protective equipment use. CONCLUSIONS: Universal use of evidence-based practices and improved medical surveillance would provide greater worker protection from LAA.

Hypovitaminosis D in infants: Evidence that increased intake of vitamin D reduces the incidence of allergic and respiratory disorders.

AIM: The study assessed the relationship between vitamin D status in infants and the presence of allergic and/or respiratory disorders. MATERIALS AND METHODS: The study cohort comprised 81 hospitalized infants presenting at the Pediatric Clinic, University Clinical Center Kragujevac, Serbia, between January 2011 and June 2016. RESULTS: The age of the infants ranged from 29 days to 12 months. All infants received prophylactic doses of vitamin D3 of 400 IU/daily until the end of the first year of life regardless of whether they are fed with adapted infant formula (n = 20) or breast milk (n = 37) or concurrently both (n = 24), up to the 5th month of life. The mean level of plasma 25(OH)D was 29.65 ng/mL. Hypovitaminosis D (mean serum level of 25(OH)D < 30 ng/mL) was found in n = 38 infants of which 6 presented with severe vitamin D deficiency (level below 10 ng/mL), 13 presented with vitamin D deficiency (level between 10 and 20 ng/mL) and 19 had vitamin D insufficiency (levels between 20 and 30 ng/mL). The median vitamin D serum level in infants with allergic disease (n = 16) was 32.35 ng/mL and in infants with respiratory disease (n = 65) 28.99 ng/mL. CONCLUSION: Daily vitamin D3 supplementation with 400 IU in infants until the end of the first year of life is too low to provide optimal defense against respiratory and/or allergic conditions.

Allergy: Mechanistic insights into new methods of prevention and therapy.

In the past few decades, the prevalence of allergic diseases has increased worldwide. Here, we review the etiology and pathophysiology of allergic diseases, including the role of the epithelial barrier, the immune system, climate change, and pollutants. Our current understanding of the roles of early life and infancy; diverse diet; skin, respiratory, and gut barriers; and microbiome in building immune tolerance to common environmental allergens has led to changes in prevention guidelines. Recent developments on the mechanisms involved in allergic diseases have been translated to effective treatments, particularly in the past 5 years, with additional treatments now in advanced clinical trials.

[Evaluation of the "Health management guideline on occupational allergy in nursing occupations and its primary prevention" by nursing managers].

OBJECTIVE: Individuals in nursing occupations are often exposed to various materials such as rubber products and drugs, and they comprise a population at high risk of developing occupational allergies. We therefore created a "Health management guideline on occupational allergy in nursing occupations and its primary prevention" (hereinafter referred to as "HMG") and conducted a questionnaire survey to elucidate its potential use and the challenges of implementing it in clinical practice. SUBJECTS AND METHODS: The HMG includes the following content: A. Basic knowledge of occupational allergies; B. Common occupational allergies in nursing occupations; C. Occupational allergies triggered by specific antigens in nursing occupations; D. Eczema and skincare for hands; and E. Health management for occupational allergies. A questionnaire survey was conducted on one nursing manager each from 80 hospitals, with at least 400 beds. The survey included questions to gauge the level of understanding the content described in the HMG and opinions on incorporating the management method. The ethics committee of the researcher's institution approved the study. RESULTS: Responses were obtained from 30 nursing managers. Over 70% responded that they understood the instructions for [occupational allergies], [common occupational allergies in nursing occupations], and [eczema and skincare for hands] presented in the HMG, and 100% said they either understood or mostly understood them. For [work management], 57% said they understood the content and 90% wanted to incorporate it. Furthermore, 10% responded that they wanted to incorporate the guidelines but did not believe it was feasible, given that "achieving general awareness and efforts involving other occupations are difficult." For [work environment management], 53% said they understood the content and 83% wanted to incorporate it. Additionally, 17% responded that they wanted to incorporate it but did not believe it was feasible, amid concerns that "allergen monitoring is difficult in reality" and "installation of local ventilation systems seems difficult." DISCUSSION AND CONCLUSIONS: The HMG was postulated to be useful in providing knowledge on occupational allergy and health management methods, and for employing in clinical practice. The study recommended that in order to specifically incorporate the management methods, it is imperative that the entire hospital, including staff from other occupations, understand the guidelines and make adjustments accordingly.

Rastreamento da hipersensibilidade metálica pelos profissionais e estudantes de saúde na prática clínico-cirúrgica / Seguimiento de la hipersensibilidad metálica por profesionales y estudiantes de salud en la práctica clínico-quirúrgica / Screening of metallic hypersensitivity by health professionals and students in clinical-surgical practice

Objetivo: investigar o rastreamento da hipersensibilidade metálica realizada pelos profissionais e estudantes de saúde durante a prática clínico-cirúrgico. Método: estudo exploratório-descritivo realizado com 228 profissionais e estudantes da área da saúde, por meio de questionário eletrônico semiestruturado, aplicado durante abril e maio de 2021, analisado por meio da estatística descritiva e da frequência de palavras. Resultados: 11,0% dos participantes realizaram a investigação sobre a hipersensibilidade metálica. 67,1% declararam que muito provavelmente poderiam incluir essa temática durante a triagem em seus atendimentos. Falta de conhecimento sobre alergia a metais e causas multifatoriais durante a prática clínico-cirúrgica foram citadas como barreiras para a implementação do rastreamento da hipersensibilidade metálica. Conclusão: pouco se evidencia o rastreamento da hipersensibilidade metálica em pacientes durante a prática clínico-cirúrgica dos profissionais e estudantes de saúde.

Objetivo: investigar el rastreo de la hipersensibilidad metálica realizada por los profesionales y estudiantes de salud durante la práctica clínico-quirúrgica. Método: estudio exploratorio-descriptivo realizado con 228 profesionales y estudiantes del área de la salud, por medio de cuestionario electrónico semiestructurado, aplicado durante abril y mayo de 2021, analizado por medio de la estadística descriptiva y de la frecuencia de palabras. Resultados: 11,0% de los participantes realizaron la investigación sobre la hipersensibilidad metálica. El 67,1% declaró que muy probablemente podrían incluir esa temática durante la selección en sus atenciones. La falta de conocimientos sobre la alergia a los metales y las causas multifactoriales durante la práctica clínico-quirúrgica se citaron como barreras para la implementación del seguimiento de la hipersensibilidad metálica. Conclusión: poco se evidencia el rastreo de la hipersensibilidad metálica en pacientes durante la práctica clínico-quirúrgica de los profesionales y estudiantes de salud.

Objective to investigate the screening of metallic hypersensitivity performed by health professionals and students during clinical-surgical practice. Method: an exploratory-descriptive study conducted with 228 health professionals and students, through a semi-structured electronic questionnaire, applied during April and May 2021, analyzed through descriptive statistics and the frequency of words. Results: 11.0% of participants conducted research on metallic hypersensitivity. 67.1% stated that they could very likely include this theme during screening in their care. Lack of knowledge about metal allergy and multifactorial causes during clinical-surgical practice were cited as barriers to the implementation of metallic hypersensitivity screening. Conclusion: there is little evidence of metallic hypersensitivity screening in patients during the clinical-surgical practice of health professionals and students.

Probiotics' Efficacy in Preventing Asthmatic Allergic Reaction Induced by Air Particles: An Animal Study.

Global air pollution and diesel exhaust particles (DEPs) generated by intratracheal instillation aggravate asthma. In this study, we evaluated the effect of probiotics via tracheal- or oral-route administration on allergies or asthma. We continuously perfused rats daily, using the oral and tracheal routes, with approximately 106-108 CFU probiotics, for 4 weeks. During this period, we used OVA-sensitized rats to build the asthma models. We orally or intratracheally administered Lactobacillus paracasei 33 (LP33) to the rats, which reduced the number of total inflammatory cells, lymphocytes, and eosinophils in the bronchoalveolar-lavage fluid, the IgE concentration, and the cytokine levels of TH2 cells, but we found no significant difference in the cytokine levels of TH1 cells. LP33 can be used to prevent asthmatic allergic reactions induced by aerosol particles. Nevertheless, the dosage form or use of LP33 needs to be adjusted to reduce the irritation of lung tissues, which may produce lesions of the trachea. We observed that DEP dosage can alleviate emphysema, and that LP33 has a substantial effect on improving or slowing allergic asthma.