Allergen-specific immunotherapy

Formulation and in-vitro characterization of fast-disintegrating herbal extract sublingual immunotherapy tablet for peanut-induced allergic asthma

Background

Allergen immunotherapy (AIT) involves the regimen of gradually incrementing doses of the allergen, thereby inducing desensitization and tolerance. Sublingual Immunotherapy tablets (SLIT-tablets) have been formulated for several allergies and had manifested efficacy for allergic rhinitis and allergic asthma. SLIT promises an alternative method to other routes of AIT enabling patients to self-administer AIT.

Objective

The study aimed to formulate fast disintegrating SLIT containing crude peanut extract for peanut-induced allergic asthma.

Methods

The crude peanut extract was prepared by a simple extraction method and was subjected to quantitative and qualitative analysis. The extract was also characterised for its physical properties. The preformulation study for the extract and excipients of the tablet was performed using FT-IR spectroscopy and Differential scanning calorimetry. The tablet powder blends were characterised for pre-compression properties. The SLIT tablets were developed by direct compression and the post-compression evaluation was performed.

Results

The results of the quantitative and qualitative analysis of extract confirmed the presence of peanut proteins in the extract. The preformulation studies using FT-IR spectroscopy and Differential Scanning Calorimetry revealed that there is no significant interaction between the CPE and excipients. The pre-compression characterisation showed that the powder blends had good flowproperties. Three doses of SLIT tablets were formulated with each dose containing four batches and the tablet of each dose was optimized by studying the effect of varying concentrations of super disintegrants on disintegration time and dissolution rate. The post compression characterization of the tablets was performed and the optimized batch of the three doses with the concentration of 5% crospovidone and 2% croscarmellose sodium showed less wetting time and high-water absorption ratio, shorter disintegration time of 14secs and maximum drug release of >90% within 2-3 min.

Conclusion

The results indicated the suitability of formulated SLIT tablets for peanut induced allergic asthma.

Effects of Local Nasal Immunotherapy with FIP-fve Peptide and Denatured Tyrophagus putrescentiae for Storage Mite-Induced Airway Inflammation

Allergic diseases are affecting public health and have increased over the last decade. Sensitization to mite allergens is a considerable trigger for allergy development. Storage mite-Tyrophagus putrescentiae shows great significance of allergenic potential and clinical relevance. The fungal immunomodulatory peptide FIP-fve has been reported to possess immunomodulatory activity. We aimed to determine whether T. putrescentiae-induced sensitization and airway inflammation in mice could be downregulated by FIP-fve in conjunction with denatured T. putrescentiae (FIP-fve and DN-Tp). Immune responses and physiologic variations in immunoglobulins, leukocyte subpopulations, cytokine productions, pulmonary function, lung pathology, cytokines in CD4⁺ and Treg cells were evaluated after local nasal immunotherapy (LNIT). After the LNIT with FIP-fve and DN-Tp, levels of specific IgE, IgG1, and IgG2a in the sera and IgA in the bronchoalveolar lavage fluid (BALF) were significantly reduced. Infiltrations of inflammatory leukocytes (eosinophils, neutrophils, and lymphocytes) in the airway decreased significantly. Production of proinflammatory cytokines (IL-5, IL-13, IL-17F and IL-23) and chemokine (IL-8) were significantly reduced, and Th1-cytokine (IL-12) increased in the airway BALF after LNIT. Pulmonary functions of Penh values were significantly decreased after the methacholine challenge, which resulted in a reduction of airway hypersensitivity after LNIT. Bronchus pathology showed a reduction of inflammatory cell infiltration and epithelium damage after LNIT. The IL-4⁺/CD4⁺ T cells could be downregulated and the IFN-γ⁺/CD4⁺ T cells upregulated. The Treg-related immunity of IL-10 and Foxp3 expressions in CD4⁺CD25⁺ cells were both upregulated after LNIT. In conclusion, LNIT with FIP-fve and DN-Tp had an anti-inflammatory effect on mite-induced airway inflammations and possesses potential as an immunomodulatory therapy agent for allergic airway diseases.

A Real-World Effectiveness of Subcutaneous Immunotherapy on the Cost of Medication, Allergic Rhinitis, and Asthma Exacerbations, as well as Upper Respiratory Tract Infection in Subjects with Allergic Rhinitis with or without Asthma: A Retrospective Pilot Study

Background and Objectives: Real-world studies are limited regarding the effectiveness of SCIT on allergic rhinitis (AR) with and without asthma and the cost of medication in Thailand. Moreover, limited data exist regarding the effectiveness of SCIT on worldwide upper respiratory tract infection (URTI). Therefore, the objective of this study was to compare the medication costs, rate of AR and asthma exacerbations, and rate of URTI in AR with or without asthma subjects before and during three years after receiving the maintenance phase of SCIT, compared with a standard usual care (SUC) group. Materials and Methods: A real-world retrospective study was conducted in AR subjects with or without asthma. From January 2001 to December 2018, 24 subjects with or without asthma received SCIT added to SUC, and 16 subjects were treated with SUC only at the Allergy and Chest Clinic of Chiang Mai Ram Hospital, Chiang Mai, Thailand. The cost of medication was recorded. AR and asthma exacerbations and URTI events were also collected. Results: From between-group comparisons, the cost of medication (THB) in the SCIT group at the one-, two-, and three-year follow up was significantly lower (587.4 (348.3–1374.6) vs. 1562.4 (1315.1–1857.3), p < 0.001, 501.2 (302.9–839.0) vs. 1728.3 (1190.0–2236.1), p < 0.001, and 372.4 (284.8–752.4) vs. 1500.3 (1217.9–1748.9), p < 0.001, respectively)), and AR and asthma exacerbations were significantly reduced at the three-year follow-up. From within-group comparisons, the cost of medication (THB) and AR and asthma exacerbations were significantly lower in the SCIT group at the one-, two-, and three-year follow-up. The URTI event was significantly reduced in the SCIT group at the two- and three-year follow-up. Conclusions: SCIT in subjects with AR with or without asthma was associated with a significantly reduced cost of medication, rates of AR and asthma exacerbations, and URTI events in the long term.

Sublingual immunotherapy increases Treg/Th17 ratio in allergic rhinitis

Background

Few studies investigated the effects of sublingual immunotherapy (SLIT) on the peripheral regulatory T cells (Tregs)/Th17 ratio.

Objective

To investigate the effectiveness of SLIT in children with allergic rhinitis (AR) and the effects on the Tregs/Th17 ratio.

Methods

This was a retrospective study of children who were treated for AR between April 2017 and March 2018 at one hospital. The patients were grouped according to the treatments they received: SLIT + pharmacotherapy vs pharmacotherapy alone.

Results

Eighty children (51 boys and 29 girls; 40/group) were included. The visual analog scale (VAS) and medication scores at 1 year in the SLIT + pharmacotherapy group were 2.70 ± 1.08 and 1.1 ± 0.8, respectively, which were lower than at baseline (7.7 ± 1.2 and 3.6 ± 1.0, respectively) (both Ps < 0.05). For the pharmacotherapy group, the VAS score was decreased at 1 year vs baseline (3.3 ± 1.2 vs 7.4 ± 1.0; P < 0.05), but the medication score did not change (P > 0.05). In the SLIT + pharmacotherapy group, the Treg percentage increased, while the Th17 percentage decreased at 1 year (both Ps < 0.01). The percentages of Tregs and Th17s did not change in the pharmacotherapy group (both Ps > 0.05).

Conclusions

SLIT + pharmacotherapy can increase the Treg percentage and decrease the Th17 percentage in the peripheral blood of children with AR.

Allergen components of Dermatophagoides farinae recognised by serum immunoglobulin (Ig)E in Thai dogs with atopic dermatitis

BACKGROUND

Dermatophagoides farinae (Der f) is a common allergen in dogs with atopic dermatitis (AD). However, the relevant components of Der f require further investigation.

OBJECTIVES

We aimed to provide data on the immunoglobulin (Ig)E-binding specific components of Der f for further diagnostic and therapeutic applications.

ANIMALS

Serum samples were collected from five healthy, nine Der f-allergic atopic and seven non-Der f-allergic atopic dogs identified based on an intradermal skin test.

METHODS AND MATERIALS

We explored the component profiles of Der f extracts through 2D gel electrophoresis and IgE immunoblotting. The IgE-binding components in both groups of atopic dogs were analysed by mass spectrometry.

RESULTS

The majority of Der f-allergic atopic dogs recognised Der f Alternaria alternata allergen 10 (Der f Alt a 10), elongation factor 1-alpha (EF1-α), gelsolin-like allergen Der f 16, Der f 28 and Der f 2. Der f 3, Der f 10, Der f 20 and Der f 32 were recognised as minor allergens. Alpha-enolase, serine protease, arginine kinase and a few hypothetical proteins were recognised components in both groups of atopic dogs. Unexpectedly, Der f 15 (chitinase) was found to be a minor component.

CONCLUSIONS AND CLINICAL IMPORTANCE

Multiple IgE-binding allergens of Der f were identified in Thai atopic dogs. We propose that the specific antigen set that is bound by IgE, comprising Der f Alt a 10, EF1-α, gelsolin-like Der f 16, Der f 28 and Der f 2, could be used for future diagnostics and immunotherapy platforms.

Improved pulmonary function test (PFT) after 1 one year of Sublingual Immunotherapy (SLIT) in unison with pharmacotherapy in mild allergic asthmatics

BACKGROUND

Allergen immunotherapy (AIT) is a promising treatment for allergic disease that induces immunological tolerance through the administration of specific allergens. The study of AIT is in its early stage and its clinical effects are not well elucidated. The present study was aimed at determining the effect of AIT on pulmonary function and serum variables of mild allergic asthma patients.

METHODS

A total of 80 patients with mild allergic asthma were recruited for the study. Allergen Specific Immunotherapy was administered in the form of Sublingual Immunotherapy and consisted of a build up phase followed by a maintenance phase (six months each respectively). Total serum IgE and vitamin D levels were quantified by ELISA. The percent eosinophill count was determined by cell analyzers. Pulmonary function test was performed at the baseline and after the end of study period. Subjective symptom score was recorded in the form of asthma control questionnaire score.

RESULTS

There was a significant increase in the pre FEV1% and pre FEV1/FVC post AIT administration. A significant decrease in the total serum IgE was found post AIT. A decrease in Asthma control Questionnaire (ACQ) scores indicated an improvement in clinical symptoms. Besides there was a significant effect on ICS discontinuation after AIT.

CONCLUSION

The study supports SLIT as an effective treatment for Immunomodulation in mild allergic asthmatics besides it gives us significant information regarding the safety and efficacy of SLIT in such patients.

Probiotics function and modulation of the immune system in allergic diseases

Allergic diseases have been a global problem over the past few decades. The effect of allergic diseases on healthcare systems and society is generally remarkable and is considered as one of the most common causes of chronic and hospitalized disease. The functional ability of probiotics to modulate the innate/acquired immune system leads to the initiation of mucosal/systemic immune responses. Gut microbiota plays a beneficial role in food digestion, development of the immune system, control/growth of the intestinal epithelial cells and their differentiation. Prescribing probiotics causes a significant change in the intestinal microflora and modulates cytokine secretion, including networks of genes, TLRs, signaling molecules and increased intestinal IgA responses. The modulation of the Th1/Th2 balance is done by probiotics, which suppress Th2 responses with shifts to Th1 and thereby prevent allergies. In general, probiotics are associated with a decrease in inflammation by increasing butyrate production and induction of tolerance with an increase in the ratio of cytokines such as IL-4, IL-10/IFN-γ, Treg/TGF-β, reducing serum eosinophil levels and the expression of metalloproteinase-9 which contribute to the improvement of the allergic disease's symptoms. Finally, it can be said that the therapeutic approach to immunotherapy and the reduction of the risk of side effects in the treatment of allergic diseases is the first priority of treatment and the final approach that completes the first priority in maintaining the condition and sustainability of the tolerance along with the recovery of the individual.

New and old adjuvants in allergen-specific immunotherapy: With a focus on nanoparticles

Allergic diseases have remarkably increased in recent years. Nowadays, efforts for curing and management of these disorders are an important concern worldwide. Allergen-specific immunotherapy (ASIT) has recently gained more attention as a means for the management of allergic diseases. Adjuvants or helper agents are materials applied for better stimulating and shifting of protective responses, and these belong to an extremely diverse collection of complexes. The main function of adjuvants includes acting as depot foundations, transferring vehicles, and immunostimulators. Immunostimulatory adjuvants have gained increasing attention for ASIT. In this regard, the present study provides a review of old and new adjuvants used in allergen immunotherapy.

Utility of Environmental Exposure Unit Challenge Protocols for the Study of Allergic Rhinitis Therapies

PURPOSE OF REVIEW

This paper explores how the Environmental Exposure Unit (EEU) experimental model can be used to further our understanding of pharmacotherapies and immunotherapies for the treatment of allergic rhinitis (AR).

RECENT FINDINGS

EEUs are used increasingly for the study of combination therapies, immunotherapies, and novel AR treatments. A combined antihistamine/corticosteroid nasal spray formulation was seen to have a faster onset of action relative to the therapies individually in the Environmental Exposure Chamber. House dust mite sublingual immunotherapy tablets are both safe and efficacious as evaluated by the Vienna Challenge Chamber. The Kingston EEU found that a novel peptide-based immunotherapy approach to be effective in reducing grass pollen-induced AR. Lastly, nasal filters were determined to reduce seasonal AR symptoms, given out-of-season in the Denmark Environmental Exposure Unit. EEUs are controlled, replicable models that provide valuable insight into the efficacy, onset and duration of action, and dose-related impacts of AR therapeutics, with direct clinical relevance.

Contraindications to immunotherapy: a global approach

BACKGROUND

Recommendations on contraindications to allergen immunotherapy (AIT) have been independently developed by National and International Societies/Academies. AIT contraindications are mainly based on case reports, case-series, or experts' opinion, while evidence-based information is limited. The aim of the present review was to describe existing guidelines on contraindications to AIT and to highlight differences between them.

MAIN BODY

An extended review of the literature regarding contraindications to AIT for respiratory allergy and venom hypersensitivity was performed. Furthermore, Societies and Academies registered in the World Allergy Organization and EAACI databases, were asked for additional information. Only AIT guidelines published under official auspicies were included. A large heterogeneity among the various recommendations on contraindications was registered. Common contraindications to most of the guidelines were: lack of adherence, pregnancy before the start of AIT, the use of beta-blockers, certain age groups, uncontrolled asthma, autoimmune diseases and malignancies.

CONCLUSION

As new data arise, revisions might soon be needed allowing AIT in the cases of patients treated with ACE inhibitors and beta-blockers, in elderly patients and in patients with concomitant autoimmune diseases and neoplasias in remission. The decision to prescribe AIT is always tailor-made, balancing risk vs benefit. Creating globally accepted guidelines would help Allergologists in their decision making.

Evaluation of Sub cutaneousRush Immunotherapy Effectiveness in Perennial Allergic Rhinitis after a Year from Treatment

INTRODUCTION

Allergen immunotherapy is an effective treatment for allergic rhinitis. Conventional immunotherapy takes at least 5 to 6 months to reach the maintenance dosage; nonetheless, rush immunotherapy accelerates to reach the maintenance dose several months earlier. However, the safety and efficacy of this treatment has not been widely investigated. The objective of the present study was to determine the efficacy of subcutaneous rush immunotherapy in the patients with perennial allergic rhinitis after a year from treatment.

MATERIALS AND METHODS

This study was carried out on a total of 15 patients with allergic rhinitis who received rush immunotherapy and were evaluated for the quality of life and clinical symptoms improvement with Sino-Nasal Outcome Test Questionnaire (SNOT-22) and Mini Rhino conjunctivitis Quality of Life Questionnaire (RQLQ) before and after a year from treatment. Moreover, specific weed mix Immunoglobulin E (IgE) was measured before and after a year from treatment. Statistical analysis was performed using SPSS software (version 16) (P<0.05).

RESULTS

The comparison of specific IgE indicated a significant reduction between before and after a year from treatment (P=0.005for pigweed)(P=0.022 for salsola). There was a significant decrease in clinical symptoms according to SNOT-22 Questionnaire [(mean score: 46.00, before the treatment) and (mean score: 14.06, after the treatment)]. The quality of life for most of the patients was moderate (46.7%) before the treatment and good (80%) after the treatment, which was considered statistically significant (P>0.001).

CONCLUSION

Rush immunotherapy is an effective treatment in the patients with allergic rhinitis. It seems to be an alternative treatment in cases that need more rapid treatment. However, it is recommended to carry out other studies on the control group.

How fast does wasp venom immunotherapy affect a regulatory T cell subpopulation (CD4+ CD25+ Foxp3+) and the synthesis of interleukins 10, 21 and transforming growth factor β1?

Introduction

The literature describes the influence of venom immunotherapy (VIT) on the subpopulation of T regulatory cells (CD4+ CD25+ Foxp3+) and the synthesis of IL-10, TGF-β1 as well as many other cytokines at various times after immunotherapy.

Aim

To assess changes in the percentage of cells of CD4+ and CD25+ in peripheral blood and serum concentrations of IL-10, IL-21 and TGF-β1 in the early stages of VIT.

Material and methods

The study included 18 patients who were allergic to wasp venom and who in the past underwent systemic anaphylactic reaction after stinging, meeting the criteria to qualify for VIT. The immunoenzymatic method (ELISA) was used to assess concentrations of cytokines IL-10, IL-21 and TGF-β1 and the surface antigens CD4 and CD25 on the cells. The concentrations were determined by flow cytometry method at baseline (before VIT) and after 2.5 and 24 h from the VIT starting point.

Results

The mean values of the activity of T lymphocytes CD4+ CD25+ FoxP3+ and concentrations of the cytokines IL-10, IL-21 and TGF-β1 are shown in table.

Conclusions

A 24-hour activation assessment of serum concentrations of cytokines IL-10, IL-21 and TGF-β1 during the first day of the Hymenoptera venom immunotherapy by ultra-rush protocol does not show the significant dynamics of change of the examined parameters.

Point-of-care ultrasonography in the allergy and immunology clinic

OBJECTIVE

To summarize evidence supporting the use of point-of-care ultrasonography as a clinical tool for allergists and immunologists.

DATA SOURCES

Cochrane Library, Medline, EMBASE, and Scopus databases were searched for articles published before December 18, 2018.

STUDY SELECTIONS

We included any retrospective or prospective study that evaluated ultrasonography in allergy and immunology and epinephrine autoinjector (EAI) needle length.

RESULTS

The standard EAI needle length may be inadequate for intramuscular delivery of epinephrine, particularly for women, at risk of anaphylaxis. In patients who weigh less than 15 kg, the lengths of commercially available EAIs may be too long, risking inadvertent intraosseous injection and resultant complications. Ultrasonography can be routinely used in the allergy clinic to guide needle length and angle for subcutaneous allergen immunotherapy injections to minimize systemic adverse effects.

CONCLUSION

Point-of-care ultrasonography can be a useful tool to enhance patient care and safety in an allergy clinic. Ideally, all patients prescribed EAIs should have ultrasonographic measurement of the skin to muscle distance and skin to bone distance to assist in identifying patients at risk of subcutaneous or intraosseous injection in anaphylaxis and those at risk of intramuscular injection during subcutaneous allergen immunotherapy injections.

Expression of recombinant allergen, Der f 1, Der f 2 and Der f 4 using baculovirus-insect cell systems

INTRODUCTION

Specific immunotherapy is critical for alleviating symptoms associated with house dust mite allergy, such as asthma and rhinitis. However, this approach relies on crude extracts, which are often not of sufficient quality or purity and are not standardized. The use of recombinant allergens may enable safer, more effective treatment.

MATERIAL AND METHODS

Using our previously constructed plasmids pET28a(+)-Der f 1, pET28a(+)-Der f 2 and pET28b(+)-Der f 4 as templates, the gene fragments coding for the allergens Der f 1, Der f 2 and Der f 4, respectively, of the dust mite Dermatophagoides farinae were amplified by PCR. Next the PCR-amplified DNAs were recovered, cloned into pFastBacHT A, and transformed into Escherichia coli DH10Bac. The resulting vectors were co-transfected into Spodoptera frugiperda Sf9 cells for expression. The recombinant allergens were purified by Ni2+ affinity chromatography, and identified by SDS-PAGE and ELISA.

RESULTS

The recombinant allergens were successfully expressed and purified from a baculovirus expression system introduced into Sf9 cells, which were verified as being of the correct predicted molecular weights by SDS-PAGE. Furthermore, the reactivity to recombinant allergens rDer f 1, rDer f 2, and rDer f 4 was 85.2%, 88.9%, and 44.4%, respectively, in 27 children with asthma and D. farinae allergy.

CONCLUSIONS

Recombinant allergens from dust mites can be successfully generated using a baculovirus-insect expression system. Furthermore, these recombinant allergens can be used to detect mite sensitivity in sera, highlighting their utility in future work to understand and develop treatment for mite allergy.

Chinese Society of Allergy Guidelines for Diagnosis and Treatment of Allergic Rhinitis

Allergic rhinitis (AR) is a global health problem that causes major illnesses and disabilities worldwide. Epidemiologic studies have demonstrated that the prevalence of AR has increased progressively over the last few decades in more developed countries and currently affects up to 40% of the population worldwide. Likewise, a rising trend of AR has also been observed over the last 2-3 decades in developing countries including China, with the prevalence of AR varying widely in these countries. A survey of self-reported AR over a 6-year period in the general Chinese adult population reported that the standardized prevalence of adult AR increased from 11.1% in 2005 to 17.6% in 2011. An increasing number of Journal Articles and imporclinical trials on the epidemiology, pathophysiologic mechanisms, diagnosis, management and comorbidities of AR in Chinese subjects have been published in international peer-reviewed journals over the past 2 decades, and substantially added to our understanding of this disease as a global problem. Although guidelines for the diagnosis and treatment of AR in Chinese subjects have also been published, they have not been translated into English and therefore not generally accessible for reference to non-Chinese speaking international medical communities. Moreover, methods for the diagnosis and treatment of AR in China have not been standardized entirely and some patients are still treated according to regional preferences. Thus, the present guidelines have been developed by the Chinese Society of Allergy to be accessible to both national and international medical communities involved in the management of AR patients. These guidelines have been prepared in line with existing international guidelines to provide evidence-based recommendations for the diagnosis and management of AR in China.

Improved efficacy of allergen-specific immunotherapy by JAK inhibition in a murine model of allergic asthma

Background

Allergen-specific immunotherapy (AIT) is the only curative treatment for type-1 allergies, but sometimes shows limited therapeutic response as well as local and systemic side effects. Limited control of local inflammation and patient symptoms hampers its widespread use in severe allergic asthma.

Objective

Our aim was to evaluate whether AIT is more effective in suppression of local inflammation if performed under the umbrella of short-term non-specific immunomodulation using a small molecule inhibitor of JAK pathways.

Methods

In C57BL/6J mice, a model of ovalbumin (OVA)-induced allergic airway inflammation and allergen-specific immunotherapy was combined with the administration of Tofacitinib (TOFA, a FDA-approved JAK inhibitor) from 48 hours prior to 48 hours after therapeutic OVA-injection. The effect of TOFA on human FOXP3⁺CD4⁺ T cells was studied in vitro.

Results

AIT combined with short-term TOFA administration was significantly more effective in suppressing total cell and eosinophil infiltration into the lung, local cytokine production including IL-1β and CXCL1 and showed a trend for the reduction of IL-4, IL-13, TNF-α and IL-6 compared to AIT alone. Furthermore, TOFA co-administration significantly reduced systemic IL-6, IL-1β and OVA-specific IgE levels and induced IgG1 to the same extent as AIT alone. Additionally, TOFA enhanced the induction of human FOXP3⁺CD4⁺ T cells.

Conclusions

This proof of concept study shows that JAK inhibition did not inhibit tolerance induction, but improved experimental AIT at the level of local inflammation. The improved control of local inflammation might extend the use of AIT in more severe conditions such as polyallergy, asthma and high-risk patients suffering from mastocytosis or anaphylaxis.

Evidence in immunotherapy for paediatric respiratory allergy: Advances and recommendations

Allergic respiratory diseases are major health problems in paediatric population due their high level of prevalence and chronicity, and to their relevance in the costs and quality of life. One of the most important risk factors for the development of airway diseases in children and adolescents is atopy. The mainstays for the treatment of these diseases are avoiding allergens, controlling symptoms, and preventing them through sustained desensitization by allergen immunotherapy (AIT). AIT is a treatment option that consists in the administration of increasing amounts of allergens to modify the biological response to them, inducing long-term tolerance even after treatment has ended. This treatment approach has shown to decrease symptoms and improve quality of life, becoming cost effective for a large number of patients. In addition, it is considered the only treatment that can influence the natural course of the disease by targeting the cause of the allergic inflammatory response. The aim of this publication is to reflect the advances of AIT in the diagnosis and treatment of allergic respiratory diseases in children and adolescents reviewing articles published since 2000, establishing evidence categories to support the strength of the recommendations based on evidence. The first part of the article covers the prerequisite issues to understand how AIT is effective, such as the correct etiologic and clinical diagnosis of allergic respiratory diseases. Following this, the article outlines the advancements in understanding the mechanisms by which AIT achieve immune tolerance to allergens. Administration routes, treatment regimens, dose and duration, efficacy, safety, and factors associated with adherence are also reviewed. Finally, the article reviews future advances in the research of AIT.

The Saudi Initiative for Asthma - 2016 update: Guidelines for the diagnosis and management of asthma in adults and children

This is an updated guideline for the diagnosis and management of asthma, developed by the Saudi Initiative for Asthma (SINA) group, a subsidiary of the Saudi Thoracic Society. The main objective of SINA is to have guidelines that are up to date, simple to understand and easy to use by nonasthma specialists, including primary care and general practice physicians. SINA approach is mainly based on symptom control and assessment of risk as it is the ultimate goal of treatment. The new SINA guidelines include updates of acute and chronic asthma management, with more emphasis on the use of asthma control in the management of asthma in adults and children, inclusion of a new medication appendix, and keeping consistency on the management at different age groups. The section on asthma in children is rewritten and expanded where the approach is stratified based on the age. The guidelines are constructed based on the available evidence, local literature, and the current situation in Saudi Arabia. There is also an emphasis on patient-doctor partnership in the management that also includes a self-management plan.

Efficacy of sublingual immunotherapy for allergic asthma: retrospective meta-analysis of randomized, double-blind and placebo-controlled trials

BACKGROUND

Allergen-specific immunotherapy (SIT) is the only available curative choice with a disease-modifying effect against respiratory allergies. The efficacy of SIT via the sublingual route was demonstrated by a number of clinical trials. This meta-analysis was performed to investigate the clinical efficacy and safety of sublingual-specific immunotherapy (SLIT) for allergic asthma.

METHODS

PubMed, EMBASE and the Cochrane Central Register of Controlled Trials were searched for randomized, double-blind and placebo-controlled (DBPC) trials evaluating the efficacy and safety of SLIT on allergic asthma. Subgroup analyses were performed according to age, type of allergen and duration of SLIT treatment.

RESULTS

Sixteen randomized DBPC trials comprising 794 patients in total met the inclusion criteria. The results suggest that SLIT significantly reduces both symptom [standardized mean difference (SMD), -0.74; P=0.006] and medication scores (SMD, -0.78; P=0.02) compared with placebo. SLIT offers a better clinical response in mite sensitive asthmatics but without confirmed proof from subgroup analyses. Prolonged duration of treatment for more than 12 months brings no additive effects. Improvement in the skin prick test was also observed following immunotherapy. There was no consistent effect on forced expiratory volume in 1 s, serum levels of antigen-specific immunoglobulin G4 and immunoglobulin E in the treated group. The risk of adverse effects was relative risk 2.23 (P=0.01).

CONCLUSIONS

SLIT is safe and clinically effective in reducing symptoms and medication use for allergic asthma. Our subgroup analyses failed to identify a disproportionate benefit of SLIT in any specific group of asthmatics, but some possible trends did emerge.

Impact of allergic rhinitis and specific subcutaneous immunotherapy on peripheral blood basophils of patients sensitized to Dermatophagoides pteronyssinus

Background

Basophils are important effectors cells in allergic rhinitis (AR) since they are involved in immunoglobulin (Ig) E – mediated inflammation and in the release of pro-inflammatory mediators. Specific subcutaneous immunotherapy (SCIT) provides clear immunologic modulation in some immune cells, however its systemic effects on basophils are not well known.

Methods

Peripheral blood (PB) samples from 43 patients with allergic rhinitis mono-sensitized to Dermatophagoides pteronyssinus (Dpt) [33 of them under SCIT with allergoid Dpt extract, in maintenance dose (SCIT), with evaluation just before SCIT injection (SCIT-T0) and 4 hours later (SCIT-T4) and the other 10 Dpt allergic patients never having, in the past, undergone specific immunotherapy treatment (NSIT)], and 15 healthy age- and gender-matched controls (HG), were analyzed. For each sample, the total (t-IgE) and specific IgE (s-IgE) was performed, as well as, the relative frequency and absolute number of PB basophils and receptor-bound IgE and IgG expression were evaluated by flow cytometry and the Histamine N-methyltransferase (HNMT) and tryptase α/β1 (TPSAB1) gene expression was assessed by real-time PCR.

Results

Higher levels of receptor-bound IgE were observed in SCIT patients, which are correlated with the levels of serum t-IgE and s-IgE, whereas no significant differences were observed for receptor-bound IgG. Regarding HNMT mRNA expression, significantly lower expression levels were detected in AR patients compared to HG, independently of type of therapy. Moreover a negative correlation was found between HNMT gene expression and time under SCIT. Conversely, tryptase gene expression was significantly up-regulated in NSIT when compared to HG; however in SCIT patients, tryptase gene expression was significantly decreased than in NSIT patients. No differences were found for any parameter between SCIT-T0 and SCIT-T4 with exception of a transient increased expression of tryptase in SCIT-T4.

Conclusion

PB basophils from patients with AR show altered functional features, which seems to be influenced by SCIT, suggesting that these cells could be useful to clarify the SCIT triggered mechanisms at a systemic level.