Efficacy and safety of the probiotic Lactobacillus paracasei LP-33 in allergic rhinitis: a double-blind, randomized, placebo-controlled trial (GA2LEN Study)

Probiotics and their Beneficial Health Effects

Probiotics are living microorganisms that are present in cultured milk and fermented food. Fermented foods are a rich source for the isolation of probiotics. They are known as good bacteria. They have various beneficial effects on human health including antihypertensive effects, antihypercholesterolemic effects, prevention of bowel disease, and improving the immune system. Microorganisms including bacteria, yeast, and mold are used as probiotics but the major microorganisms that are used as probiotics are bacteria from the genus Lactobacillus, Lactococcus, Streptococcus, and Bifidobacterium. Probiotics are beneficial in the prevention of harmful effects. Recently, the use of probiotics for the treatment of various oral and skin diseases has also gained significant attention. Clinical studies indicate that the usage of probiotics can alter gut microbiota composition and provoke immune modulation in a host. Due to their various health benefits, probiotics are attaining more interest as a substitute for antibiotics or anti-inflammatory drugs leading to the growth of the probiotic market.

HMGN2 and Histone H1.2: potential targets of a novel probiotic mixture for seasonal allergic rhinitis

Background

Allergic rhinitis (AR) is a common nasal inflammatory disorder that severely affects an individual's quality of life (QoL) and poses a heavy financial burden. In addition to routine treatments, probiotic intervention has emerged as a promising strategy for preventing and alleviating allergic diseases. The main objective of this study was to determine the effect of a novel multi-strain probiotic mixture on AR symptoms and investigate potential targets underlying the probiotic intervention.

Methods

A randomized, double-blind, placebo-controlled clinical study was conducted on AR patients who were allergic to autumnal pollens (n = 31). Placebo or a novel probiotic mixture, composed of Lactobacillus rhamnosus (L. rhamnosus) HN001, L. acidophilus NCFM, Bifidobacterium lactis (B. lactis) Bi-07, L. paracasei LPC-37, and L. reuteri LE16, was administered after 2 months. The therapeutic efficacy was evaluated by a symptom assessment scale. Before and during the pollen season, blood samples were collected, and peripheral blood mononuclear cells (PBMCs) were isolated for further tandem mass tags (TMTs)-based quantitative proteomic analyses. Potential targets and underlying pathological pathways were explored using bioinformatics methods.

Results

During the pollen season, the rhinoconjunctivitis symptom score of participants who were administered probiotics (probiotic group, n = 15) was significantly lower than those administered placebo (placebo group, n = 15) (P = 0.037). The proteomic analyses identified 60 differentially expressed proteins (DEPs) in the placebo group, and subsequent enrichment analyses enriched a series of pathways and biological processes, including signaling pathways of inflammation, coagulation cascade, lipid, carbohydrate and amino acid metabolic pathways, and transcription and translation processes. Least Absolute Shrinkage and Selection Operator (LASSO) regression extracted five main elements, namely, GSTO1, ATP2A2, MCM7, PROS1, and TRIM58, as signature proteins. A total of 17 DEPs were identified in the probiotic group, and there was no pathway enriched. Comparison of DEPs in the two groups revealed that the expression levels of the high-mobility group nucleosome-binding domain-containing protein 2 (HMGN2) and Histone H1.2 presented an opposite trend with different interventions.

Conclusion

Our data showed that AR symptoms alleviated after treatment with the novel multi-strain probiotic mixture, and the proteomic analyses suggested that HMGN2 and Histone H1.2 might be targets of probiotic intervention for seasonal AR.

Probiotics and the Potential of Genetic Modification as a Possible Treatment for Food Allergy

Food allergy is a common condition that affects millions of people worldwide. It is caused by an abnormal immune response to harmless food antigens, which is influenced by genetics and environmental factors. Modulating the gut microbiota and immune system with probiotics or genetically modified probiotics confers health benefits to the host and offers a novel strategy for preventing and treating food allergy. This systematic review aims to summarize the current proof of the role of probiotics in food allergy and propose a promising future research direction of using probiotics as a possible strategy of treatment for food allergy.

A, Chadha B. Comparative Case Study of Efficacy of Oral Bilastine Monotherapy to Concomittant Administration of Oral Bilastine with Probiotic in Patients with Allergic Rhinitis

Introduction

Allergic rhinitis continues to pose a global burden in both adult and paediatric population and requires adequate medical therapy to avoid long term complications making it a challenging concern. This prompts the need to find a suitable and appropriate treatment regimen for this condition.

Aim

To study the clinical efficacy of Oral Bilastine and Probiotics in patients with allergic rhinitis. To compare the effectiveness of Bilastine monotherapy to Oral Bilastine combined with Probiotics in patients with allergic rhinitis.

Materials and Methods

Total of 100 patients were selected and randomized into two groups- Group 1 and Group 2 and were treated with Oral Bilastine 20 mg OD and Oral Bilastine 20 mg with Oral Probiotics OD (Lactobacillus fermentum & L. paracasei - 4 billion cells) respectively to maintain uniformity. Baseline scoring and follow up scoring after 6 weeks was done using the Total symptom score, Absolute eosinophil count and Nasal smear eosinophil count and were evaluated and documented as per their response to treatment.

Results

A significant reduction was observed in the severity of symptoms especially nasal obstruction, sneezing in patients of both groups along with extra nasal symptoms, with average mean score in Group 1 being 7.72 before treatment that reduced to 3.66 and that of Group 2 from 9.32 to 5.02. The mean score of Group 2 was greater in both before and after treatment which is highly significant. (p < 0.001).

Conclusion

Monotherapy with Oral Bilastine has proven in relieving allergic symptoms. Addition of Oral Probiotics along with Bilastine has shown to have synergistic effect in further improving overall symptoms in allergic rhinitis.

Efficacy and safety of gastrointestinal microbiome supplementation for allergic rhinitis: A systematic review and meta-analysis with trial sequential analysis

BACKGROUND

Allergic rhinitis (AR) is a non-infective chronic inflammatory disease of nasal mucosa.

PURPOSE

To evaluate the efficacy and safety of gastrointestinal microbiome supplementation (GMS) for patients with allergic rhinitis (AR), concerning improvement on symptoms and signs, laboratory outcomes, quality of life, and medication scores.

METHODS

Five English databases were searched up to Dec 12th, 2022. Probiotics, prebiotics, and synbiotics were main therapies or adjuvants in experimental groups. Systematic reviews and meta-analyses were conducted based on the Cochrane systematic review method by using RevMan 5.4 Software, with meta-influence analyses, subgroup-analyses, meta-regression, and publication bias performed for exploration of heterogeneity by Stata V.14. Trial sequential analyses were performed by TSA 0.9, and quality of the results was accessed through the GRADE-pro GDT.

RESULTS

Finally, extracted from 53 articles, 65 RCTs involving 3,634 participants with sound worldwide representativeness were included. Primary results showed better improvement in GMS groups on TNSS (WMD=1.05, P for WMD=0.004, 95%CI:0.34 to 1.76), overall nasal condition (WMD=1.25, P for WMD<0.001, 95%CI:0.90 to 1.61), overall quality of life (WMD=6.16, P for WMD<0.001, 95%CI:4.92 to 7.40) and medication score (WMD=0.42, P for WMD=0.42, 95%CI:-0.06 to 0.90).However, GMS groups were inferior than the controls concerning reduction on serum total IgE (WMD=-1.81) and ratios of serum Th1/Th2 (WMD=-1.06). Meta-regressions suggested significant (p<0.05) variations of the effects in some comparisons. In addition, results of sub-group analyses firstly revealed potential influence between final results and the variables above. Instantly after intervention, the GRADE levels of evidence were sound, including "High ⨁⨁⨁⨁" in 10, "Moderate ⨁⨁⨁◯" in 33, and "Low ⨁⨁◯◯" in nine comparisons. However, overall certainties decreased obviously during follow-ups.

CONCLUSION

Overall, our pooled results firstly revealed that GMS yielded acceptable benefits for patients with AR compared with controls with sound certainties, after balancing the benefits and harms.

Assessment of a Multispecies Probiotic Supplement for Relief of Seasonal Allergic Rhinitis: A Randomized Double-Blind Placebo-Controlled Trial

Background: Early phase clinical research provided initial support for the use of a multispecies probiotic supplement to improve quality of life (QoL) in adults with seasonal allergic rhinitis (AR) and reduce the use of AR symptom relieving medication. This study aimed to confirm these early phase findings in a double-blind randomized placebo-controlled trial. Methods: Individuals, aged 18-65 years, with a minimum 2-year history of AR, moderate-to-severe AR symptoms, and a positive radio-allergosorbent test to Bermuda (Couch) Grass were randomized to receive either a multispecies probiotic supplement (total colony-forming units 4 × 10⁹/day) or placebo twice daily for 8 weeks. A mini-rhinoconjunctivitis quality of life questionnaire (mRQLQ) scale was administered at screening, days 0, 28, and 56. The proportion of participants with a >0.7 improvement in mRQLQ was the primary outcome. Participants also completed a daily symptom and medication diary during the supplementation period. Results: There were 165 participants randomized, with 142 included in the primary outcome analysis. The percentage of participants meeting the threshold for a clinically meaningful reduction in the mRQLQ from days 0 to 56 was not significantly different between groups (61% vs. 62%, p = 0.90). However, 76 participants had a clinically meaningful improvement in QoL (decrease in mRQLQ >0.7) prior to the start of supplementation (screening to day 0). Conclusion: Changes in self-reported QoL and other disease severity metrics between screening and the start of supplementation limited the ability to discern an effect of supplementation and highlight the need for adaptive clinical trial designs in allergy research. Clinical Trial Registration: The trial was registered with the Australia and New Zealand Clinical Trials Registry (ACTRN12619001319167).

Lacticaseibacillus paracasei GM-080 Ameliorates Allergic Airway Inflammation in Children with Allergic Rhinitis: From an Animal Model to a Double-Blind, Randomized, Placebo-Controlled Trial

Background: Probiotics may facilitate the clinical management of allergic diseases. However, their effects on allergic rhinitis (AR) remain unclear. We examined the efficacy and safety of Lacticaseibacillus paracasei GM-080 in a mouse model of airway hyper-responsiveness (AHR) and in children with perennial AR (PAR) by using a double-blind, prospective, randomized, placebo-controlled design. Methods: The production of interferon (IFN)-γ and interleukin (IL)-12 was measured by using an enzyme-linked immunosorbent assay. GM-080 safety was evaluated via the whole-genome sequencing (WGS) of virulence genes. An ovalbumin (OVA)-induced AHR mouse model was constructed, and lung inflammation was evaluated by measuring the infiltrating leukocyte content of bronchoalveolar lavage fluid. A clinical trial was conducted with 122 children with PAR who were randomized to receive different doses of GM-080 or the placebo for 3 months, and their AHR symptom severity scores, total nasal symptom scores (TNSSs), and Investigator Global Assessment Scale scores were examined. Results: Among the tested L. paracasei strains, GM-080 induced the highest IFN-γ and IL-12 levels in mouse splenocytes. WGS analysis revealed the absence of virulence factors or antibiotic-resistance genes in GM-080. The oral administration of GM-080 at 1 × 10⁷ colony forming units (CFU)/mouse/day for 8 weeks alleviated OVA-induced AHR and reduced airway inflammation in mice. In children with PAR, the oral consumption of GM-080 at 2 × 10⁹ CFU/day for 3 months ameliorated sneezing and improved Investigator Global Assessment Scale scores significantly. GM-080 consumption led to a nonsignificant decrease in TNSS and also nonsignificantly reduced IgE but increased INF-γ levels. Conclusion: GM-080 may be used as a nutrient supplement to alleviate airway allergic inflammation.

The efficacy and safety of Yupingfeng Powder with variation in the treatment of allergic rhinitis: Study protocol for a randomized, double-blind, placebo-controlled trial

Background: Allergic rhinitis (AR) is an upper airways chronic inflammatory disease mediated by IgE, which affects 10%-20% of the population. The mainstay for allergic rhinitis nowadays include steroids and antihistamines, but their effects are less than ideal. Many patients therefore seek Chinese medicine for treatment and Yupingfeng Powder is one of the most common formulae prescribed. In this study, we aim to investigate the efficacy and safety of Yupingfeng Powder with variation for the treatment of allergic rhinitis. Study design: This is a double-blind, randomized, placebo-controlled trial. A 2-week screening period will be implemented, and then eligible subjects with allergic rhinitis will receive interventions of either "Yupingfeng Powder with variation" granules or placebo granules for 8 weeks, followed by post treatment visits at weeks 12 and 16. The change in the Total Nasal Symptom Score (TNSS) will be used as the primary outcome. Discussion: This trail will evaluate the efficacy and safety of Yupingfeng Powder in treating allergic rhinitis. The study may provide the solid evidence of Yupingfeng Powder with variation can produce better clinical efficacy than the placebo granules. Trial registration: ClinicalTrials.gov, identifier NCT04976023.

Role of Probiotics in Patients with Allergic Rhinitis: A Systematic Review of Systematic Reviews

Introduction  Allergic rhinitis (AR) is estimated to affect up to 30% of the world population. With the rise in cases, newer treatment modalities have been explored. Probiotics have shown to reduce symptoms of AR and improve quality of life. A few systematic reviews have been published aiming to assess the role of probiotics in AR. Objectives  To consolidate the recent evidence with an overview of systematic reviews by extracting data regarding subjective outcomes (from quality of life questionnaires, the Total Nasal Symptom Score, the Total Ocular Symptom Score, the Daily Total Symptom Score, the incidence of AR, and the Rhinitis Total Symptom Score) and objective outcomes (levels of antigen-specific immunoglobulin E [IgE], total IgE, interleukin 10 [IL-10], interferon gamma [IFNG], eosinophil, and the T helper 1/T helper 2 [Th1/Th2] ratio). Data Synthesis  We conducted a literature search on the PubMed, EBSCO CINAHL, EBSCO Dentistry & Oral Sciences Source, and Cochrane Library up to April 14, 2020. The qualitative assessment was performed using the Assessing the Methodological Quality of Systematic Reviews (AMSTAR-2) tool. A total of 419 titles were screened, and 3 systematic reviews met our eligibility criteria. Probiotics in the treatment of AR have been shown to improve quality of life, the total nasal and ocular symptom scores, the daily total symptom scores and Th1/Th2 ratio. No difference was ascertained for rhinitis total symptom score, and the rates of antigen-specific IgE, total IgE, IL-10, INFG and eosinophil. Conclusion  The present review showed that there is considerable evidence that probiotics are useful in the treatment of AR. Further randomized trials targeting the limitations of the currently-available evidence can help ascertain the usefulness of probiotics in cases of AR.

Effects of Probiotics on Allergic Rhinitis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

BACKGROUND

The prevalence of allergic rhinitis has been estimated to range from 10 to 30% in adults and up to 40% in children. Probiotics have been tested as for this condition, but no census on which probiotic types are most effective.

OBJECTIVE

Our aim of this study was to provide probiotic strain-specific evaluation for the treatment of allergic rhinitis.

METHODS

Databases (PubMed, Google Scholar, and ScienceDirect) were searched (from inception to October 2020) to identify randomized controlled trials (RCTs) of probiotic treatments in allergic rhinitis patients. A systematic review was done comparing types of reported outcomes, clinical and immunological parameters and safety data. A meta-analysis was done for probiotics with at least two RCTs per probiotic strain(s) and sharing a common outcome.

RESULTS

A total of 13 randomized, double-blind, placebo-controlled trials (N = 1591 participants) were included in the systematic review. Overall, 8 of 9 probiotic types alleviated at least one clinical symptom of allergic rhinitis. The meta-analysis results showed that, neither L. paracasei Lp33 (SMD = -1.61, 95% CI -4.67, 1.45) nor L. rhamnosus GG (SMD = -1.00, 95% CI -3.01, 1.00) had significant efficacy for reducing nasal symptom scores.

CONCLUSIONS

Our analysis showed probiotics produced a slight improvement in some clinical and immunological measurements on allergic rhinitis. Due to the diversity of outcome measurements and lack of sufficient trials for each probiotic strain, future trials are needed with similar study design and uniform outcomes to better compare the effect of probiotics on allergic rhinitis.

Genomic Insight Into Lacticaseibacillus paracasei SP5, Reveals Genes and Gene Clusters of Probiotic Interest and Biotechnological Potential

The Lacticaseibacillus paracasei species is comprised by nomadic bacteria inhabiting a wide variety of ecological niches, from fermented foodstuffs to host-associated microenvironments. Lc. paracasei SP5 is a novel strain, originally isolated from kefir grains that presents desirable probiotic and biotechnological attributes. In this study, we applied genomic tools to further characterize the probiotic and biotechnological potential of the strain. Firstly, whole genome sequencing and assembly, were performed to construct the chromosome map of the strain and determine its genomic stability. Lc. paracasei SP5 carriers several insertion sequences, however, no plasmids or mobile elements were detected. Furthermore, phylogenomic and comparative genomic analyses were utilized to study the nomadic attributes of the strain, and more specifically, its metabolic capacity and ability to withstand environmental stresses imposed during food processing and passage through the gastrointestinal (GI) tract. More specifically, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Carbohydrate-active enzyme (CAZymes) analyses provided evidence for the ability of the stain to utilize an array of carbohydrates as growth substrates. Consequently, genes for heat, cold, osmotic shock, acidic pH, and bile salt tolerance were annotated. Importantly bioinformatic analysis showed that the novel strain does not harbor acquired antimicrobial resistance genes nor virulence factors, in agreement with previous experimental data. Putative bacteriocin biosynthesis clusters were identified using BAGEL4, suggesting its potential antimicrobial activity. Concerning microbe-host interactions, adhesins, moonlighting proteins, exopolysaccharide (EPS) biosynthesis genes and pilins mediating the adhesive phenotype were, also, pinpointed in the genome of Lc. paracasei SP5. Validation of this phenotype was performed by employing a microbiological method and confocal microscopy. Conclusively, Lc. paracasei SP5 harbors genes necessary for the manifestation of the probiotic character and application in the food industry. Upcoming studies will focus on the mechanisms of action of the novel strain at multiple levels.

The Efficacy and Safety of Probiotics for Allergic Rhinitis: A Systematic Review and Meta-Analysis

Background

Probiotics have proven beneficial in a number of immune-mediated and allergic diseases. Several human studies have evaluated the efficacy and safety of probiotics in allergic rhinitis; however, evidence for their use has yet to be firmly established.

Objective

We undertook a systematic review and meta-analysis aiming to address the effect and safety of probiotics on allergic rhinitis.

Methods

We systematically searched databases [MEDLINE (PubMed), Embase, and the Cochrane Central Register of Controlled Trials] from inception until June 1, 2021. Qualified literature was selected according to inclusion and exclusion criteria, the data were extracted, and a systematic review and meta-analysis was conducted.

Results

Twenty-eight studies were included. The results showed that probiotics significantly relieved allergic rhinitis symptoms (standardized mean difference [SMD], -0.29, 95% confidence interval (CI) [-0.44, -0.13]; p = 0.0003, I ² = 89%), decreased Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) scores compared with the control group (SMD, -0.64, 95% CI [-0.79, -0.49], p < 0.00001, I ² = 97%), and increased T helper cell 1(Th1)/Th2 ratio (mean difference [MD], -2.47, 95% CI [-3.27, -1.68], p < 0.00001, I ² = 72%). There was no significant change in overall or specific IgE levels between probiotic-treated and placebo-treated subjects (SMD, 0.09, 95% CI [-0.16, 0.34], I ² = 0%, and SMD, -0.03, 95% CI [-0.18, 0.13], p = 0.72, I ² = 0%, respectively).

Conclusions

To sum up, probiotic supplement seems to be effective in ameliorating allergic rhinitis symptoms and improving the quality of life, but there is high heterogeneity in some results after subgroup analysis and clinicians should be cautious when recommending probiotics in treating allergic rhinitis.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, PROSPERO (CRD42021242645).

Efficacy and Safety of Lactobacillus reuteri CCFM1040 in Allergic Rhinitis and Asthma: A Randomized, Placebo-Controlled Trial

The coexistence of allergic rhinitis (AR) and asthma reinforces the concept of “one airway, one disease,” which has prompted the exploration for a single intervention to treat both diseases. Lactobacillus reuteri CCFM1040 (CCFM1040) was found to be an inhibitor of the common pathogenesis of AR and asthma in our previous studies. This study presented a randomized, placebo-controlled trial to investigate the clinical effects of CCFM1040 on both diseases. The total symptom score (TSS), the quality of life (QoL), and the modulation in the gut microbiota of patients with AR, the Asthma Control and Test (ACT) of patients with asthma, and the safety of both AR and asthma were measured. In patients with AR, CCFM1040 numerically decreased TSS, Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), 3 nasal scores in TSS (nasal congestion, watery eyes, and rhinorrhea), and sleep and significantly improved (P = 0.014) non-nose/eye symptoms. The ACT score was numerically increased in patients with asthma (from partially controlled to well-controlled). Significant microbial (from class level to genus level) and metabolic differences (P < 0.05) were found in patients with AR. No adverse reactions were observed. No effect on the blood and urine routine indexes. CCFM1040 has a potential benefit on both diseases. Further studies based on these findings will help to optimize the management of AR and asthma.

Effects of therapeutic probiotics on modulation of microRNAs

Probiotics are beneficial bacteria that exist within the human gut, and which are also present in different food products and supplements. They have been investigated for some decades, due to their potential beneficial impact on human health. Probiotics compete with pathogenic microorganisms for adhesion sites within the gut, to antagonize them or to regulate the host immune response resulting in preventive and therapeutic effects. Therefore, dysbiosis, defined as an impairment in the gut microbiota, could play a role in various pathological conditions, such as lactose intolerance, gastrointestinal and urogenital infections, various cancers, cystic fibrosis, allergies, inflammatory bowel disease, and can also be caused by antibiotic side effects. MicroRNAs (miRNAs) are short non-coding RNAs that can regulate gene expression in a post-transcriptional manner. miRNAs are biochemical biomarkers that play an important role in almost all cellular signaling pathways in many healthy and disease states. For the first time, the present review summarizes current evidence suggesting that the beneficial properties of probiotics could be explained based on the pivotal role of miRNAs. Video Abstract.

Administration of Lactobacillus paracasei HB89 mitigates PM2.5-induced enhancement of inflammation and allergic airway response in murine asthma model

PM2.5 causes abnormal immune response and asthma in animals. In this study, a Balb/c mouse animal model was exposed to PM2.5 to induce asthma. Lactobacillus paracasei HB89 was fed at the same time, in order to observe whether L. paracasei HB89 mitigates respiratory tract allergies stimulated by PM2.5. The results showed that PM2.5 stimulated a significant increase in white blood cells and immunoglobulin (IgE) in OVA-induced allergic Balb/c mice, and IgE in the blood further triggered the release of histamine in the lung immune cells. This not only increased overall immune cell counts, but the lymphocyte counts also increased significantly, resulting in significant inhibitions of cytokines INF-r and TGF-β, and induction of IL-4, IL-5, IL-13 and IL-17a. After feeding with HB89, apart from the absence of observable changes in body weight, the total white blood cell count in the animal blood and IgE response were also be reduced; the proliferation of immune cells in the lungs caused by PM2.5 was slowed down; and histamine and cytokines INF-r and TGF-β were secreted in large quantities, but IL- 4, IL-5, IL-13, IL-17a were inhibited, which effectively reduced the possibility of asthma induction.

Probiotics in Medicine: A Long Debate

During the last years probiotics gained the attention of clinicians for their use in the prevention and treatment of multiple diseases. Probiotics main mechanisms of action include enhanced mucosal barrier function, direct antagonism with pathogens, inhibition of bacterial adherence and invasion capacity in the intestinal epithelium, boosting of the immune system and regulation of the central nervous system. It is accepted that there is a mutual communication between the gut microbiota and the liver, the so-called “microbiota-gut-liver axis” as well as a reciprocal communication between the intestinal microbiota and the central nervous system through the “microbiota-gut-brain axis.” Moreover, recently the “gut-lung axis” in bacterial and viral infections is considerably discussed for bacterial and viral infections, as the intestinal microbiota amplifies the alveolar macrophage activity having a protective role in the host defense against pneumonia. The importance of the normal human intestinal microbiota is recognized in the preservation of health. Disease states such as, infections, autoimmune conditions, allergy and other may occur when the intestinal balance is disturbed. Probiotics seem to be a promising approach to prevent and even reduce the symptoms of such clinical states as an adjuvant therapy by preserving the balance of the normal intestinal microbiota and improving the immune system. The present review states globally all different disorders in which probiotics can be given. To date, Stronger data in favor of their clinical use are provided in the prevention of gastrointestinal disorders, antibiotic-associated diarrhea, allergy and respiratory infections. We hereby discuss the role of probiotics in the reduction of the respiratory infection symptoms and we focus on the possibility to use them as an adjuvant to the therapeutic approach of the pandemic COVID-19. Nevertheless, it is accepted by the scientific community that more clinical studies should be undertaken in large samples of diseased populations so that the assessment of their therapeutic potential provide us with strong evidence for their efficacy and safety in clinical use.

Probiotics as a functional food ingredient in allergic diseases: regulation of CD4+ T helper cell differentiation

Allergic diseases are increasing worldwide, associating with increased health costs and decreased quality of life. Allergy is immune-related diseases caused by an allergic immune response to innocuous substance in the environment. At present, research has focussed on the study of the relevance to the microbiome and the phenotypes of allergy, including the relationships among the gastrointestinal microbiome, immune function, and allergic sensitisation. Probiotics as functional food ingredient are thought to secrete functional metabolites that have antibacterial effects on ameliorating intestinal health and CD4+ T helper cells-mediated immunity. This review will summarise the role of probiotics in the immune regulation and flora balance, highlighting recent advances in our understanding of the imbalance of Th subsets and cytokine leading to the immunopathology of allergic reactions. Finally, we discussed the unresolved problems and future research directions in order to promote the clinical application of probiotics immunotherapy.

A critical review of antibiotic resistance in probiotic bacteria

Probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit upon the host. At present, probiotics are gaining popularity worldwide and are widely used in food and medicine. Consumption of probiotics is increasing with further in-depth research on the relationship between intestinal flora and host health. Most people pay more attention to the function of probiotics but ignore their potential risks, such as infection and antibiotic resistance transfer to pathogenic microbes. Physiological functions, effects and mechanisms of action of probiotics were covered in this review, as well as the antibiotic resistance phenotypes, mechanisms and genes found in probiotics. Typical cases of antibiotic resistance of probiotics were also highlighted, as well as the potential risks (including pathogenicity, infectivity and excessive immune response) and corresponding strategies (dosage, formulation, and administration route). This timely study provides an avenue for further research, development and application of probiotics.

Bio-functional properties of probiotic Lactobacillus: current applications and research perspectives

Lactic acid bacteria as a starter culture are very important component in the fermentation process of dairy and food industry. Application of lactic acid bacteria as probiotic bacteria adds more functionality to the developed product. Gut colonizing bacteria have attractive benefits related to human health. Bio-functional properties such as antimicrobial activity, anti-inflammatory, ACE-inhibitory, antioxidant, antidiarrheal, antiviral, immunomodulatory, hypocholesterolemic, anti-diabetic and anti-cancer activities are the most applicable research areas of lactic acid bacteria. Different strains of Lactobacillus are generally consumed as probiotics and colonize the gastrointestinal tract. Sometimes these bacteria may possess antimicrobial activity and may positively influence the effect of antibiotics. Use of Lactobacillus spp. for the development of functional foods is one of the promising areas of current research and applications. Individual bacterial species have unique biological activity, which may vary from strains to strains and identification of this uniqueness could be helpful in the development of functional and therapeutic food products.

Probiotic NVP-1703 Alleviates Allergic Rhinitis by Inducing IL-10 Expression: A Four-week Clinical Trial

Although several recent studies reported that probiotics might be beneficial for allergic rhinitis (AR), the effect of probiotics on AR is not consistent and have not been reproduced between studies. We aimed to determine the efficacy and safety of probiotic NVP-1703, a mixture of Bifidobacterium longum and Lactobacillus plantarum, in subjects with perennial AR. Adult subjects with perennial AR received either NVP-1703 (n = 47) or placebo (n = 48) for four weeks. Total nasal symptom scores (TNSS), rhinitis control assessment test (RCAT), blood eosinophil count, allergen-specific IgE, and immunological parameters in serum and urine were compared at baseline and after four weeks. TNSS changes from baseline at weeks 1, 3, and 4 were significant between the NVP-1703 and placebo groups (p = 0.033, 0.031, and 0.029, respectively). RCAT score showed significant differences between the NVP-1703 and placebo groups (p = 0.049) at week 4. Dermatophagoides farinae-specific IgE levels and serum IL-10 levels were significantly different between the NVP-1703 and placebo groups (p = 0.033 and p = 0.047, respectively). IL-10/IL-4 and IL-10/IL-13 ratios were different between the NVP-1703 and placebo groups at week 4 (p = 0.046 and 0.018, respectively). NVP-1703 treatment reduced urinary prostaglandin F_2α and leukotriene E₄ levels (p > 0.05). Therefore, NVP-1703 can be treatment option for perennial AR.

Synopsis

Akute entzündliche Reaktionen bzw. der akute Infekt mit Restitutio ad integrum laufen in einer perfekt modulierten Kaskade ab, bei dem eine akute inflammatorische Einleitungsphase von einer antiinflammatorischen Phase und einer Entzündungsauflösungsphase abgelöst werden.

Effects of a probiotic treatment (Enterococcus faecalis) and open-label placebo on symptoms of allergic rhinitis: study protocol for a randomised controlled trial

INTRODUCTION

Several studies suggest that gut microbiota may play an important role in allergic diseases. The present trial aims to examine effects of the probiotic Enterococcus faecalis on symptoms of allergic rhinitis in patients. Effects of this probiotic on the immune system have been reported by several studies, but the majority of the previous trials were animal studies. In addition, it is well known that symptoms in allergic rhinitis are prone to exhibit high placebo responses. Moreover, recent studies report that even placebos without deception (open-label placebos) are highly effective in reducing symptoms of allergic rhinitis. Our study design combines both new approaches to assess effects on allergic symptoms in patients. The objective of this study is to compare the effects of a probiotic treatment (E. faecalis) with effects seen by open-label placebo, concealed placebo treatment and no treatment control.

METHODS AND ANALYSIS

A total of 120 patients with allergic rhinitis will be randomly assigned to one of four different groups: a double-blind probiotic/placebo group (groups 1 and 2), an open-label placebo group (group 3) and a no-treatment group (group 4) to control for spontaneous variation of symptoms. The primary outcome is the evaluation of allergic symptoms using the Combined Symptoms Medication Score. Furthermore, health-related quality of life is examined (Rhinitis Quality of Life Questionnaire). Secondary outcomes include a visual analogue scale on allergic burden and a second quality of life questionnaire. This report describes the study design of the randomised controlled trial.

ETHICS AND DISSEMINATION

The study design was approved by the ethical committee of the UKT Department of Psychosomatic Medicine and Psychotherapy, Tübingen, Germany. The trial is registered at the German Clinical Trials Register (www.drks.de, DRKS00015804). The trial results will be published in peer-reviewed journals and at conferences.

TRIAL REGISTRATION NUMBER

German Clinical Trials Register (www.drks.de, DRKS00015804); Pre-results.

Efficacy of probiotic in perennial allergic rhinitis under five year children: A randomized controlled trial

Objective:

To determine the efficacy of probiotic (Lactobacillus Paracasei, LP-33) and compare it with cetirizine for the treatment of perennial allergic rhinitis in under five year’s children.

Methods:

The randomised clinical trial was conducted at Kharadar General Hospital, Karachi, from Dec 2016 to Nov 2017. Children aged 6 to 60 months, clinically presented with allergic rhinitis were included in the study. Total 212 children, randomized into intervention group A (received probiotic LP-33) and control group B (received cetirizine) for six weeks, were included in the analysis. Baseline allergic rhinitis symptoms (rhinorrhea, sneezing, nasal blocking, coughing, feeding & sleeping difficulties) were assessed after two and six weeks follow up and correlated both groups by using Pearson chi-square test. A p value of <0.05 were considered statistically significant.

Results:

Total 212 children were analysed, out of them 113 (53.3%) were male. Mean age of study participant was 26 ± 16.64 months and mean body weight was 10.1 ± 3.26 Kg. More than 95% cases have shown significant improvement in their baseline symptoms (rhinorrhea, sneezing, nasal blocking, coughing, feeding difficulties and sleeping difficulties) in both intervention (L-33 Probiotic) and control (Cetirizine) groups. Statistically there was no difference in effectiveness of probiotic and cetirizine treatment for perennial allergic rhinitis (P > 0.05).

Conclusions:

Probiotic (LP-33) was equally effective as cetirizine in under five year’s children for the treatment of perennial allergic rhinitis. Probiotic has additional benefit to treat allergic rhinitis without causing any major side effect in children reported by the study.

A significant decrease in the gene expression of interleukin-17 following the administration of synbiotic in patients with allergic rhinitis who underwent immunotherapy: A placebo-controlled clinical trial

Background:

Allergic Rhinitis (AR) is the most common allergic disease worldwide. The present study, evaluated effects of synbiotic on gene expression of interferon-gamma (IFN-γ), interleukin-4 (IL-4), interleukin-10 (IL-10), interleukin-17 (IL-17), transforming growth factor beta (TGF-β), and forkhead box P3 (FoxP3) in AR patients who received concomitant immunotherapy in a placebo-controlled clinical trial.

Materials and Methods:

Twenty AR patients were randomized in synbiotic and placebo groups and received cluster immunotherapy for 2 months. RNA was extracted from peripheral PBMCs, then the cDNA synthesized. Subsequently, SYBR Green real-time Reverse transcription polymerase chain reaction technique was employed for studying the expression of mentioned genes. In addition, SNOT-22 and mini-Rhinoconjunctivitis Quality of Life Questionnaire questionnaires were completed by patients. Data were analyzed before and also 2 and 6 months after intervention.

Results:

Clinical symptoms and quality of life were improved with immunotherapy, but there was no significant difference between the placebo and synbiotic groups. Gene expression of IFN-γ, TGF-β, and FoxP3 was increased whereas the gene expression of IL-4 and IL-10 decreased, but not significant. Interestingly, the gene expression of IL-17 in the synbiotic group was significantly decreased versus placebo after 2 months (P = 0.001) and also at the end of intervention (P = 0.0001) comparing with the time zero.

Conclusion:

Significant reduction in the IL-17 gene expression following administration of synbiotic versus placebo shows the importance of synbiotic in control of the immunopathogenesis of AR. Further studies with more samples are recommended. In addition, evaluating the effects of synbiotic in patients who do not undergo immunotherapy is suggested to get a better conclusion.

Chinese herbal medicine bi min fang for allergic rhinitis: protocol for a double-blind, double-dummy, randomized controlled trial

BACKGROUND

People with allergic rhinitis (AR) often seek help from Chinese medicine due to dissatisfaction with conventional treatments. Lung-spleen qi deficiency syndrome (LSQDS) is the most common type of AR, and the Chinese herbal medicine formula bi min fang (BMF) is commonly prescribed for AR patients with LSQDS. However, direct evidence supporting its efficacy and safety is not available, and its potential mechanism of action remains unclear.

METHODS/DESIGN

This paper presents a double-blind, double-dummy, randomized controlled trial. After a 2-week run-in period, 80 AR patients with LSQDS will be recruited and randomly allocated to the BMF group or the control group in a 1:1 ratio. The patients in the BMF group will receive BMF and the placebo for levocetirizine hydrochloride orally, while the control group participants will receive levocetirizine hydrochloride and the placebo for BMF orally. All participants will receive 4 weeks of treatment and 12 weeks of follow-up. The primary outcome is a change in the Total Nasal Symptom Score (TNSS). Secondary outcomes include changes in scores for the standard version of the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ(S)), and visual analog scale (VAS); changes in serum levels of the cytokines interleukin-4, interferon-γ, transforming growth factor β-1, and interleukin-17; and changes in the gut microbiota composition in the stool. The TNSS, RQLQ(S), and VAS will be recorded at the beginning of, middle of and after the treatment period and at the end of each month in the 3-month follow-up period. Blood and stool samples will be collected at baseline and the end of the treatment. The aforementioned four cytokines will be detected in the serum using enzyme-linked immunosorbent assays, and the stool gut microbiota will be detected using 16S ribosomal ribonucleic acid sequencing. Any side effects of the treatment will be recorded.

DISCUSSION

The results of this trial will provide consolidated evidence of the effect of BMF on AR and the potential mechanism by which BMF acts. This study will be the first to explore the mechanism of action of Chinese herbal medicine on the gut microbiota in AR.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR-IPR-17010970 . Registered on 23 March 2017.

Treatment of allergic rhinitis using mobile technology with real-world data: The MASK observational pilot study

BACKGROUND

Large observational implementation studies are needed to triangulate the findings from randomized control trials as they reflect "real-world" everyday practice. In a pilot study, we attempted to provide additional and complementary insights on the real-life treatment of allergic rhinitis (AR) using mobile technology.

METHODS

A mobile phone app (Allergy Diary, freely available in Google Play and Apple App stores) collects the data of daily visual analog scales (VAS) for (i) overall allergic symptoms, (ii) nasal, ocular, and asthma symptoms, (iii) work, as well as (iv) medication use using a treatment scroll list including all medications (prescribed and over the counter (OTC)) for rhinitis customized for 15 countries.

RESULTS

A total of 2871 users filled in 17 091 days of VAS in 2015 and 2016. Medications were reported for 9634 days. The assessment of days appeared to be more informative than the course of the treatment as, in real life, patients do not necessarily use treatment on a daily basis; rather, they appear to increase treatment use with the loss of symptom control. The Allergy Diary allowed differentiation between treatments within or between classes (intranasal corticosteroid use containing medications and oral H1-antihistamines). The control of days differed between no [best control], single, or multiple treatments (worst control).

CONCLUSIONS

This study confirms the usefulness of the Allergy Diary in accessing and assessing everyday use and practice in AR. This pilot observational study uses a very simple assessment (VAS) on a mobile phone, shows novel findings, and generates new hypotheses.

Microbiome and Allergic Diseases

Allergic diseases, such as respiratory, cutaneous, and food allergy, have dramatically increased in prevalence over the last few decades. Recent research points to a central role of the microbiome, which is highly influenced by multiple environmental and dietary factors. It is well established that the microbiome can modulate the immune response, from cellular development to organ and tissue formation exerting its effects through multiple interactions with both the innate and acquired branches of the immune system. It has been described at some extent changes in environment and nutrition produce dysbiosis in the gut but also in the skin, and lung microbiome, inducing qualitative and quantitative changes in composition and metabolic activity. Here, we review the potential role of the skin, respiratory, and gastrointestinal tract (GIT) microbiomes in allergic diseases. In the GIT, the microbiome has been proven to be important in developing either effector or tolerant responses to different antigens by balancing the activities of Th1 and Th2 cells. In the lung, the microbiome may play a role in driving asthma endotype polarization, by adjusting the balance between Th2 and Th17 patterns. Bacterial dysbiosis is associated with chronic inflammatory disorders of the skin, such as atopic dermatitis and psoriasis. Thus, the microbiome can be considered a therapeutical target for treating inflammatory diseases, such as allergy. Despite some limitations, interventions with probiotics, prebiotics, and/or synbiotics seem promising for the development of a preventive therapy by restoring altered microbiome functionality, or as an adjuvant in specific immunotherapy.

Microbial Delivery Vehicles for Allergens and Allergen-Derived Peptides in Immunotherapy of Allergic Diseases

Allergen-specific immunotherapy represents the only available curative approach to allergic diseases. The treatment has proven effective, but it requires repetitive administrations of allergen extracts over 3-5 years and is often associated with adverse events. This implies the need for novel therapeutic strategies with reduced side effects and decreased treatment time, which would improve patients' compliance. Development of vaccines that are molecularly well defined and have improved safety profile in comparison to whole allergen extracts represents a promising approach. Molecular allergy vaccines are based on major allergen proteins or allergen-derived peptides. Often, such vaccines are associated with lower immunogenicity and stability and therefore require an appropriate delivery vehicle. In this respect, viruses, bacteria, and their protein components have been intensively studied for their adjuvant capacity. This article provides an overview of the microbial delivery vehicles that have been tested for use in allergy immunotherapy. We review in vitro and in vivo data on the immunomodulatory capacity of different microbial vehicles for allergens and allergen-derived peptides and evaluate their potential in development of allergy vaccines. We also discuss relevant aspects and challenges concerning the use of microbes and their components in immunotherapy of allergic diseases.

House dust mite-related respiratory allergies and probiotics: a narrative review

The socio-economic burden of allergic respiratory conditions on continental Europe is even higher than that of mainstream diseases, such as diabetes and cardiovascular disease, as allergic rhinitis alone accounts for billions of Euros in healthcare expenses across Europe. House dust mites (HDM) are one of the most common triggers behind allergic rhinitis and asthma. The role of probiotics in the treatment and prevention of some allergic conditions, such as atopic dermatitis, is already well recognized, whereas evidence about their efficacy in patients with respiratory allergies—while increasing—is still limited. Here the current evidence for the use of probiotics in patients with allergic rhinitis and/or asthma is discussed.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

Probiotics (Lactobacillus gasseri KS-13, Bifidobacterium bifidum G9-1, and Bifidobacterium longum MM-2) improve rhinoconjunctivitis-specific quality of life in individuals with seasonal allergies: a double-blind, placebo-controlled, randomized trial

Background: Rhinoconjunctivitis-specific quality of life is often reduced during seasonal allergies. The Mini Rhinoconjunctivitis Quality of Life Questionnaire (MRQLQ) is a validated tool used to measure quality of life in people experiencing allergies (0 = not troubled to 6 = extremely troubled). Probiotics may improve quality of life during allergy season by increasing the percentage of regulatory T cells (Tregs) and inducing tolerance.Objective: The objective of this study was to determine whether consuming Lactobacillus gasseri KS-13, Bifidobacterium bifidum G9-1, and B. longum MM-2 compared with placebo would result in beneficial effects on MRQLQ scores throughout allergy season in individuals who typically experience seasonal allergies. Secondary outcomes included changes in immune markers as part of a potential mechanism for changes in MRQLQ scores.Design: In this double-blind, placebo-controlled, parallel, randomized clinical trial, 173 participants (mean ± SEM: age 27 ± 1 y) who self-identified as having seasonal allergies received either a probiotic (2 capsules/d, 1.5 billion colony-forming units/capsule) or placebo during spring allergy season for 8 wk. MRQLQ scores were collected weekly throughout the study. Fasting blood samples were taken from a subgroup (placebo, n = 37; probiotic, n = 35) at baseline and week 6 (predicted peak of pollen) to determine serum immunoglobulin (Ig) E concentrations and Treg percentages.Results: The probiotic group reported an improvement in the MRQLQ global score from baseline to pollen peak (-0.68 ± 0.13) when compared with the placebo group (-0.19 ± 0.14; P = 0.0092). Both serum total IgE and the percentage of Tregs increased from baseline to week 6, but changes were not different between groups.Conclusions: This combination probiotic improved rhinoconjunctivitis-specific quality of life during allergy season for healthy individuals with self-reported seasonal allergies; however, the associated mechanism is still unclear. This trial was registered at clinicaltrials.gov as NCT02349711.

Probiotics and Allergic Rhinitis: A Simon Two-Stage Design to Determine Effectiveness

BACKGROUND

Allergic rhinitis (AR) is a chronic upper respiratory disease affecting 10-30% of the population worldwide. It associated with significant economic and medical burden. Probiotics have received attention in recent years as a novel strategy to treat infectious/immune conditions, including AR. However, substantiation of these health claims by regulatory bodies has been rejected due, in part, to inadequate clinical trial design. While randomized controlled trials are considered the gold standard for assessing clinical efficacy, such trials require a priori preclinical data on effect size, which may be a reason for the conflicting results in the probiotic and AR literature. Progressive clinical trial designs, such as the Simon Two-Stage Design, are showing promise within the area of integrative and alternative medicine, particularly in relation to probiotic supplementation, to obtain empirical data for the design of clinical trials that meet regulatory requirements.

METHODS

This Phase II study uses a Simon Two-Stage Design to determine the response rate of patients with AR to a probiotic supplement. Patients will consume a multispecies probiotic twice daily for 8 weeks, and will attend an allergy clinic at the beginning and end of the intervention period for assessment. Symptom improvement following probiotic supplementation will be measured by the mini-Rhinoconjunctivitis Quality of Life Questionnaire. Secondary outcomes include twice-weekly symptom and medication diaries, objective determination of nasal congestion via Nasal Rhinomanometry, and change in frequency of medication usage.

DISCUSSION

This study provides an exemplar of the value of using a progressive study design in the complementary and alternative medicine setting. A Simon Two-Stage Design was adopted to investigate whether a multispecies probiotic supplement, not yet trialed in the context of AR, has promise as a therapeutic intervention and warrants the design of larger placebo-controlled studies.

Viruses and bacteria in Th2-biased allergic airway disease

Allergic airway diseases are typically characterized by a type 2-biased inflammation. Multiple distinct viruses and bacteria have been detected in the airways. Recently, it has been confirmed that the microbiome of allergic individuals differs from that of healthy subjects, showing a close relationship with the type 2 response in allergic airway disease. In this review, we summarize the recent findings on the prevalence of viruses and bacteria in type 2-biased airway diseases and on the mechanisms employed by viruses and bacteria in propagating type 2 responses. The understanding of the microbial composition and postinfectious immune programming is critical for the reconstruction of the normal microflora and immune status in allergic airway diseases.

Dietary modifications for refractory chronic rhinosinusitis? Manipulating diet for the modulation of inflammation

BACKGROUND

An endotype of chronic rhinosinusitis (CRS) refractory to medical and surgical management is characterized by persistent T-helper 1/T-helper 17 inflammation of the sinus mucosa, which potentially facilitates colonization with dysbiotic microbial flora. Dietary interventions that target reduction of systemic inflammation are increasingly recommended as adjuncts to ongoing medical therapy in chronic disorders with a strong inflammatory component, such as cardiac disease, diabetes, and metabolic syndrome. Inflammation-reducing dietary modifications may thus be of benefit in patients with refractory CRS (RCRS).

OBJECTIVE

To identify nonpharmacologic approaches that implicate modification of dietary factors, potentially reducing systemic level of inflammation in RCRS.

METHODS

A systematic review of the literature was undertaken to identify dietary strategies for reducing inflammation in metabolic syndrome, diabetes, and cardiac disease. Mechanistic-based strategies for reducing systemic inflammation were identified and categorized to identify potential therapeutic avenues, which would be applicable to RCRS.

RESULTS

Principal mechanisms for altering inflammation at the systemic level via dietary manipulation center around (1) increased consumption of foods with anti-inflammatory properties, and (2) modulation of the gut microbiome to reduce short-chain fatty acid secretion by dysbiotic gut flora. Recommended dietary modifications to reduce systemic markers of inflammation or to improve RCRS include alteration of macronutrient intake, alterations in consumption of meat and fats, consumption of prebiotics and probiotics, and a low-salicylate diet in the context of aspirin-exacerbated respiratory disease.

CONCLUSION

Dietary modifications may offer a potential nonpharmacologic means of reducing inflammation in patients with RCRS and hence may represent a complementary adjunct to existing medical therapies. Additional prospective studies are required to further validate the concept of dietary modifications in patients with RCRS to support the findings.

The Use of Adjuvants for Enhancing Allergen Immunotherapy Efficacy

One key approach to increase the efficacy and the safety of immunotherapy is the use of adjuvants. However, many of the adjuvants currently in use can cause adverse events, raising concerns regarding their clinical use, and are geared toward productive immune responses but not necessarily tolerogenic responses. Thus, novel adjuvants for immunotherapy are needed and are being developed. Essential is their potential to boost appropriate tolerogenic adaptive immune responses to allergens while limiting side effects. This review provides an overview of adjuvants currently in clinical use or under development and discusses their therapeutic effect in enhancing allergen-induced tolerance.

Do probiotics have a role in the treatment of allergic rhinitis? A comprehensive systematic review and meta-analysis

OBJECTIVE

To investigate clinical evidence for the efficacy of probiotics in the treatment of allergic rhinitis (AR).

METHODS

A systematic search was conducted to review the results of all randomized, double-blind, placebo-controlled trials by following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement. Primary outcome measurements were total nasal and ocular symptom scores (SS) and quality of life (QoL) questionnaires. Secondary outcome measurements were individual nasal SS and immunologic parameters.

RESULTS

Twenty-two randomized, double-blind, placebo-controlled studies were included. Seventeen trials showed significant benefit of probiotics clinically, whereas eight trials showed significant improvement in immunologic parameters compared with placebo. All five studies with Lactobacillus paracasei (LP) strains demonstrated clinically significant improvements compared with placebo. Probiotics showed significant reduction in nasal and ocular SS (standardized mean difference [SMD], -1.23, p < 0.001; and SMD, -1.84, p < 0.001; respectively), total, nasal, and ocular QoL scores compared with placebo (SMD, -1.84, p < 0.001; SMD, -2.30, p = 0.006; and SMD, -3.11, p = 0.005; respectively). Although heterogeneity was high, in subgroup analysis, SMD for total nasal and ocular symptoms with patients with seasonal AR and for nasal QoL scores for studies with LP-33 strain were significant and homogenous. Scores of nasal blockage, rhinorrhea, and nasal itching were significantly lower in the probiotic group compared with placebo. The meta-analysis studies SS the Japanese guidelines revealed a significant, homogenous SMD score of -0.34 for individual nasal SS, above the minimal important clinical difference value of 0.3. The T-helper 1 to T-helper 2 ratio was significantly lower in the probiotic group compared with placebo (SMD, -0.78; p = 0.045).

CONCLUSION

Despite high variability among the studies, synthesis of available data provided significant evidence of beneficial clinical and immunologic effects of probiotics in the treatment of AR, especially with seasonal AR and LP-33 strains. With the rising pool of studies, the most promising strains in specific allergies can be revealed and adjuvant therapy with probiotics can be recommended for the treatment of AR.

Oral administration of Lactobacillus paracasei NCC 2461 for the modulation of grass pollen allergic rhinitis: a randomized, placebo-controlled study during the pollen season

Background

The efficacy of Lactobacillus paracasei NCC 2461 in modulating allergic rhinitis was previously evaluated in two exploratory clinical studies. Oral administration with NCC 2461 reduced specific subjective symptoms following nasal provocation tests with controlled grass pollen allergen concentrations. Our aim was to confirm the anti-allergic effect of NCC 2461 in grass pollen allergic subjects exposed to natural doses of allergens during the pollen season.

Findings

A double-blind, randomized, placebo-controlled, parallel study was conducted with 131 grass pollen allergic subjects from May to July 2012 in concomitance with the pollen season in Berlin. NCC 2461 or placebo was administered daily for an 8-week period to adult subjects with clinical history of allergic rhinitis to grass pollen, positive skin prick test and IgE to grass pollen. During the 8 weeks, symptoms and quality of life questionnaires were filled out, and plasma was collected for IgE analysis at screening and at the end of the intervention. All subjects were included within a 5-day interval, ensuring exposure to similar air pollen counts for each individual during the trial period. The results obtained show that symptoms increased with pollen loads, confirming a natural exposure to the allergen and presence of pollen-induced allergic rhinitis in the subjects. However, no significant differences were observed in allergic rhinitis symptoms scores, quality of life, or specific IgE levels between subjects receiving NCC 2461 as compared to placebo administration.

Conclusion

In contrast to previous findings, oral administration of NCC 2461 did not show a beneficial effect on allergic rhinitis in a field trial. The influence of study design, allergen exposure and intervention window on the efficacy of NCC 2461 in modulating respiratory allergy should be further evaluated.

Electronic supplementary material

The online version of this article (doi:10.1186/s13601-015-0085-4) contains supplementary material, which is available to authorized users.

Allergy associations with the adult fecal microbiota: Analysis of the American Gut Project

BACKGROUND

Alteration of the gut microbial population (dysbiosis) may increase the risk for allergies and other conditions. This study sought to clarify the relationship of dysbiosis with allergies in adults.

METHODS

Publicly available American Gut Project questionnaire and fecal 16S rRNA sequence data were analyzed. Fecal microbiota richness (number of observed species) and composition (UniFrac) were used to compare adults with versus without allergy to foods (peanuts, tree nuts, shellfish, other) and non-foods (drug, bee sting, dander, asthma, seasonal, eczema). Logistic and Poisson regression models adjusted for potential confounders. Odds ratios and 95% confidence intervals (CI) were calculated for lowest vs highest richness tertile. Taxonomy associations considered 122 non-redundant taxa (of 2379 total taxa) with ≥ 0.1% mean abundance.

RESULTS

Self-reported allergy prevalence among the 1879 participants (mean age, 45.5 years; 46.9% male) was 81.5%, ranging from 2.5% for peanuts to 40.5% for seasonal. Fecal microbiota richness was markedly lower with total allergies (P = 10(-9)) and five particular allergies (P ≤ 10(-4)). Richness odds ratios were 1.7 (CI 1.3-2.2) with seasonal, 1.8 (CI 1.3-2.5) with drug, and 7.8 (CI 2.3-26.5) with peanut allergy. These allergic participants also had markedly altered microbial community composition (unweighted UniFrac, P = 10(-4) to 10(-7)). Total food and non-food allergies were significantly associated with 7 and 9 altered taxa, respectively. The dysbiosis was most marked with nut and seasonal allergies, driven by higher Bacteroidales and reduced Clostridiales taxa.

INTERPRETATION

American adults with allergies, especially to nuts and seasonal pollen, have low diversity, reduced Clostridiales, and increased Bacteroidales in their gut microbiota. This dysbiosis might be targeted to improve treatment or prevention of allergy.

Evaluation of the potential anti-allergic effects of heat-inactivated Lactobacillus paracasei V0151 in vitro, ex vivo, and in vivo

The efficacy of Lactobacillus paracasei V0151 (V0151), isolated from the faeces of a child, to modulate immune responses was investigated. In RAW 264.7 cells expressing an inducible nitric oxide synthase (iNOS)-directed luciferase gene, heat-inactivated V0151 stimulated iNOS expression followed by nitric oxide production. V0151 significantly elevated interferon gamma, interleukin (IL)-10, tumour necrosis factor alpha, and IL-1β production in human peripheral blood mononuclear cells. In splenocytes isolated from ovalbumin (OVA)-sensitised BALB/c mice treated with OVA and V0151 at different bacterium-to-cell ratios (1:1, 10:1, and 20:1) for 96 h, IL-2, IL-4, IL-5, and IL-13 production was dose-dependently downregulated, whereas IL-12 was dose-dependently upregulated. Collectively, our findings indicate that V0151 might regulate pro-inflammatory factors in macrophages and splenocytes. Furthermore, the T helper 1/T helper 2 (Th1/Th2) balance was also skewed toward Th1 dominance through the elevation of Th1 cytokine production.

A systematic review and meta-analysis of probiotics for the treatment of allergic rhinitis

BACKGROUND

Probiotics have proven beneficial in a number of immune-mediated and allergic diseases. Several human studies have evaluated the efficacy of probiotics in allergic rhinitis; however, evidence for their use has yet to be firmly established. The current systematic review seeks to synthesize the results of available randomized trials.

METHODS

In a systematic review and meta-analysis, the Medline, EMBASE, and Cochrane Library databases were reviewed and randomized controlled trials (RCTs) were extracted based on defined inclusion criteria. The effect of probiotics on Rhinitis Quality of Life (RQLQ) scores, Rhinitis Total Symptom Scores (RTSS), as well as total and antigen-specific serum immunoglobulin E (IgE) levels were evaluated by meta-analysis.

RESULTS

A total of 23 studies with 1919 patients were identified, including 21 double-blind RCTs and 2 randomized crossover studies. Multiple probiotic strains, study populations, and outcome measures were used in individual trials. Seventeen studies showed a significant clinical benefit from the use of probiotics in at least 1 outcome measure when compared to placebo, whereas 6 trials showed no benefit. Among the trials eligible for meta-analysis, the use of probiotics resulted in a significant improvement in RQLQ scores compared to placebo (standard mean difference [SMD] -2.23; p = 0.02). Probiotics had no effect on RTSS (SMD -0.36; p = 0.13) or total IgE levels (SMD 0.01; p = 0.94), although there was a trend toward a reduction in antigen-specific IgE (SMD 0.20; p = 0.06) in the placebo group compared to probiotic.

CONCLUSION

Probiotics may be beneficial in improving symptoms and quality of life in patients with allergic rhinitis; however, current evidence remains limited due to study heterogeneity and variable outcome measures. Additional high-quality studies are needed to establish appropriate recommendations.

Daily intake of probiotics with high IFN-γ/IL-10 ratio increases the cytotoxicity of human natural killer cells: a personalized probiotic approach

A personalized probiotic microfluidic chip system has been established and used to screen the probiotics which had the highest value of IFN-γ/IL-10 or IL-10/IFN-γ among six probiotics, including L. paracasei BRAP01, L. acidophilus AD300, B. longum BA100, E. faecium BR0085, L. rhamnosus AD500, and L. reuteri BR101. One hundred volunteers were included and their PBMCs were collected and stimulated by the six probiotics. People who belonged to the IFN-γ group took the probiotics that exerted the highest ratio of IFN-γ/IL-10 and vice versa in IL-10 group. A significant increase in NK cytotoxicity of 69 volunteers in the IFN-γ group was observed compared to the IL-10 group (n = 21) and control group (n = 10). The result also showed that L. paracasei BRAP01 and L. acidophilus AD300 were the two dominant inducers in IFN-γ group which yielded higher value of IFN-γ/IL-10 than the other 4 probiotics, while L. reuteri BR101 was the most effective agent on the ratio of IL-10/IFN-γ in the IL-10 group. Our finding highlighted the concept of personalized probiotics and also provided a good foundation to investigate the probiotics with NK activity.

Current recommendations and emerging options for the treatment of allergic rhinitis

Allergic rhinitis (AR) is one of the most common diseases and represents a global health problem, currently affecting up to 30% of the general population, with a continuously increasing prevalence and significant comorbidities and complications. The aim of this review is to provide an update on AR treatment, with a focus on current therapies defined by AR and its impact on asthma guidelines and with a particular emphasis on new and future therapeutic perspectives.