House dust mite-specific immunotherapy alters the basal expression of T regulatory and FcεRI pathway genes

IFNG, FCER1A, PCDHB10 expression as a new potential marker of efficacy in grass pollen allergen-specific immunotherapy

Introduction

Allergen-specific immunotherapy (AIT) is the core treatment in allergic rhinitis and asthma. Although widely used, some patients do not benefit from treatment and there is no efficacy objective marker.

Aim

To define the profile of gene transcripts during the build-up phase of AIT and their comparison to the control group and then search for a viable efficacy marker in relation to patient symptoms.

Material and methods

AIT was administered in 22 patients allergic to grass pollen. Analysis of 15 selected transcript expression was performed in whole blood samples taken before AIT (sample A) and after reaching the maintenance dose (sample B). The control group included 25 healthy volunteers (sample C). The primary endpoint was Relative Quantification. The gene expression analysis was followed by clinical evaluation with the use of Allergy Control Score (ACS).

Results

Comparison between samples A and B of gene expression showed a significant increase in IFNG expression (p = 0.03). In relation to the control group, pretreatment samples from patients showed higher levels of AFAP1L1 (p = 0.006), COMMD8 (p = 0.001), PIK3CD (p = 0.027) and TWIST2 (p = 0.0003) in univariate analysis. A generalized linear regression model was built according to the Bayesian Information Criterion based on the IFNG, FCER1A and PCDHB10 expression pattern for prediction of the AIT outcome. The model showed a correlation in predicted and observed changes in ACS.

Conclusions

There is a significant change in the expression of IFNG during the build-up phase of AIT. The authors propose an in vitro model of AIT efficacy prediction for further validation.

The Role of Pai-1 Gene 4g/5g Polymorphism and Diagnostic Value of Biomarkers in Allergic and Non-Allergic Asthma Phenotype

SUMMARY – Asthma is a chronic inflammatory disease that is characterized by reversible obstruction of airways, bronchial hyper-reactivity and airway remodeling. The etiology of asthma is multifactorial, with inheritance playing an important role. The aim of our study was to investigate the importance of biomarkers of asthma and the role of plasminogen activator inhibitor-1 (PAI-1) gene as a genetic factor that could be involved in the pathogenesis of asthma. The research was conducted at Jordanovac University Department for Lung Diseases and Croatian Institute of Transfusion Medicine. The research included 149 patients with asthma and 89 healthy individuals. We collected demographic data of both study groups, determined asthma severity using GINA guidelines, and the values of biomarkers and PAI-1 by using laboratory techniques. Based on the results, we concluded that patients with allergic phenotype of asthma were younger, had better lung function and higher levels of IgE. By observing FeNO values, we were not able to distinguish asthmatic patients that had been diagnosed with obstruction of airways from asthmatic patients with normal lung function because FeNO indicates the inflammatory component of disease. The 4G/5G polymorphism of PAI-1 gene did not show any statistically significant difference in the distribution of 4G/4G, 4G/5G and 5G/5G between the group of asthmatic patients and control group.

Immunological Changes Induced in Peach Allergy Patients with Systemic Reactions by Pru p 3 Sublingual Immunotherapy

SCOPE

Sublingual immunotherapy using peach extract enriched in Pru p 3 (Pru p 3-enriched-SLIT) brings a new perspective to treating patients with allergy to lipid transfer proteins. We evaluate the immunological changes induced by Pru p 3-enriched-SLIT during one year.

METHODS AND RESULTS

Three groups are included: peach allergic patients who receive Pru p 3-enriched-SLIT, peach allergic untreated patients, and controls. Peripheral blood mononuclear cells are obtained before treatment and at different time-points. Monocyte-derived dendritic cells (moDCs) maturation and lymphocyte proliferation are assessed by flow cytometry. Data showed a significant reduction of moDCs maturation status during one year of treatment and an increase in PD-L1. Moreover, we observed a significant decrease of the Pru p 3-specific proliferation of effector cells and an increase in regulatory T (Treg) cells with higher PD-L1 expression and IL-10 production. These are observed in patients treated only.

CONCLUSION

Successful Pru p 3-enriched-SLIT is linked to an important immunosuppression of allergen-specific effector T cells, potentially due to an increase of allergen-specific Treg cells. These cellular changes are orchestrated by the activity of moDCs promoting the expression of PD-L1 that will participate in the regulatory response. These changes may serve as biomarkers during SLIT alongside other features such as IgE/IgG₄ ratio.

Long-term effects of allergen-specific subcutaneous immunotherapy for house dust mite induced allergic rhinitis

Background:

Allergic rhinitis is strongly associated with the presence of house dust mites. This study investigated the long-term effects of allergen-specific immunotherapy. Allergen-specific immunotherapy was applied over three years. The study was based on a 10-year follow up of patients with allergic rhinitis.

Methods:

The study was conducted between 2001 and 2015. Skin prick test results and symptom scores were evaluated before (26 patients) and after 3 years (20 patients) of allergen-specific immunotherapy (using data from a previously published study), and 10 years after allergen-specific immunotherapy had ended (20 of 26 patients).

Results:

The symptom scores before allergen-specific immunotherapy were significantly higher than those obtained after 3 years of allergen-specific immunotherapy and 10 years after allergen-specific immunotherapy (p < 0.0175). There were no significant differences between the scores obtained at 3 years and 10 years after allergen-specific immunotherapy (p > 0.0175).

Conclusion:

Subcutaneous immunotherapy is an effective treatment for house dust mite induced allergic rhinitis.

House dust mite allergy: Its innate immune response and immunotherapy

Over the past few decades, allergic diseases have become increasingly prevalent worldwide. House dust mite (HDM) is the most important domestic source for allergic diseases such as allergic rhinitis, asthma and atopic dermatitis. Dermatophagoides pteronyssinus (Der p) is the major environmental allergen in southeast Asia because of the humid and warm environment is suitable for its growth. In the recent year, role of HDM allergen in allergic inflammation through innate immune system has been well studied. Toll-like receptors (TLRs), protease-activated receptors (PARs) and DC-SIGN could be activated by different HDM major allergens and proinflammatory cytokines also be upregulated. Treatment efficacy for HDM allergy is unsatisfied to the patients and the medication is limited. Immunotherapy provided an alternative option for treating HDM allergy through targeted to the mechanisms of allergic reaction and represented a long-term symptoms relief. Gene specific immunotherapy was currently being developed and it could decrease allergic inflammation and improve the efficacy of treatment. In this report, we reviewed recent studies about the role of HDM allergy in innate immune system and its immunotherapy. Understanding the HDM allergen induced signal transduction pathway and developed allergen specific immunotherapy could help physicians to create precise diagnosis and solve unmet need in HDM allergy.

Polymorphism 4G/5G of the plasminogen activator inhibitor 1 gene as a risk factor for the development of allergic rhinitis symptoms in patients with asthma

Plasminogen activator inhibitor-1 (PAI-1) is a glycoprotein which has a role in tissue remodelling after inflammatory processes. The objective is to investigate the frequency of PAI-1 gene polymorphism (4G/5G) in patients with a lung ventilation dysfunction in asthma and allergic rhinitis. Genomic DNA was isolated and genotypes of polymorphism of PAI-1 4G/5G and ABO were determined using the methods of RT-PCR and PCR-SSP. Study group includes 145 adult patients diagnosed with chronic asthma, with all clinically relevant parameters and the laboratory markers of pO₂, IgE and eosinophils in sputum and nasal swab. In the processing of data, appropriate statistical tests (Kolmogorov-Smirnov test, median, interquartile ranges, χ ² and Mann-Whitney U tests) were used. Patients with symptoms of allergic rhinitis were significantly younger and had an almost four time higher levels of IgE (P = 0.001), higher pO₂ (P = 0.002) and PEF (P = 0.036), compared to those who do not have these symptoms. Genotype PAI 4G/4G is significantly more common in patients with allergic rhinitis (28.1% vs. 16.1%; P = 0.017) compared to the genotype 5G/5G. Carriers of the genotype 4G/5G also have a borderline statistical significance. There were no statistically significant difference in the incidence of allergic rhinitis in the carriers of any ABO genotypes. The frequency of PAI genotype 4G/4G is significantly more common in patients with allergic rhinitis. The results suggest that the carriers of at least one 4G allele are at a higher risk for developing symptoms of allergic rhinitis in asthma.

Initial immunological changes as predictors for house dust mite immunotherapy response

BACKGROUND

Although specific immunotherapy is the only aetiological treatment for allergic disorders, the underlying mechanisms are not fully understood. Specific immunotherapy induces changes in lymphocyte Th subsets from Th2 to Th1/Treg. Whether differences in immunological patterns underlie patient response to immunotherapy has not yet been established.

OBJECTIVES

We studied the immunological changes occurring during a 1-year period of Dermatophagoides pteronyssinus (DP) immunotherapy and their relation with clinical outcome.

METHODS

We included 34 patients with DP allergy who received subcutaneous specific immunotherapy (SCIT) for 1 year. Following treatment, patients were classified as responders or non-responders. Fourteen allergic subjects who did not receive SCIT were included as controls. Peripheral blood was obtained at 0, 1, 3, 6 and 12 months and cultured with nDer p 1. Phenotypic changes, cytokine production and basophil response were analysed by flow cytometry; transcription factors were measured by mRNA quantification. Serum immunoglobulin levels were also measured.

RESULTS

After 1 year of SCIT, 82% of cases showed improved symptoms (responders). Although increases in sIgG4 were observed, BAT reactivity was not modified in these patients. Increases in T-BET/FOXP3 as well as nDer p 1-specific Th1/Treg frequencies were also observed, along with a decrease in Th2, Th9 and Th17. These changes corresponded to changes in cytokine levels.

CONCLUSION

Patients who respond well to DP-SCIT show immunological differences compared to non-responders. In responders, basal differences include a lower frequency of Th1 and higher frequencies of Th2, Th9 and Th17 cells. After 1 year of treatment, an increased production of sIgG4 was observed in responders, along with a change in Th2 response towards Th1/Treg.

The Functional IgE-Blocking Factor Induced by Allergen-Specific Immunotherapy Correlates with IgG4 Antibodies and a Decrease of Symptoms in House Dust Mite-Allergic Children

BACKGROUND

At present, there are no validated biomarkers reflecting or predicting the clinical efficacy of allergen-specific immunotherapy (AIT) . We aimed to investigate the correlations between clinical and immunological responses of patients undergoing house dust mite (HDM) AIT.

METHODS

Sixty-nine children diagnosed with HDM allergic rhinitis and/or asthma received standardized Dermatophagoides pteronyssinus (Dp) subcutaneous AIT for 12 months. Twenty HDM-allergic children served as an open control group. Clinical symptom and medication scores were recorded and Dp-specific IgE, IgG4 and IgE-blocking factor were measured before AIT and after 4 and 12 months of AIT.

RESULTS

Symptom scores decreased after 4 months and continued to decrease during 12 months of AIT. No differences in medication scores were observed between AIT and the control group during the study period. Levels of Dp IgG4 increased after 4 months and correlated to symptom scores at 12 months (r = -0.296, p = 0.013) of AIT. The Dp IgE-blocking factor increased after 4 months of AIT, and correlated with symptom scores at 4 months (r = -0.307, p = 0.010) and 12 months (r = -0.288, p = 0.016) of AIT. A strong correlation between Dp IgE-blocking factor and Dp IgG4 during AIT (4 months: r = 0.680; 12 months: r = 0.636, both p < 0.0001) was observed. Patients with IgE-blocking factor ≥0.2 after 4 months of AIT showed lower symptom scores at 12 months of AIT (p = 0.0093).

CONCLUSIONS

Subcutaneous HDM AIT results in a decrease of allergic symptoms among HDM-allergic children. IgE-blocking activity increased after 4 months of AIT and correlated with clinical symptoms. A high IgE-blocking factor at an early stage of AIT is associated with fewer symptoms at a later stage of AIT.

The safety of specific immunotherapy for patients allergic to house-dust mites and pollen in relation to the development of neoplasia and autoimmune disease: a long-term, observational case-control study

BACKGROUND

Specific immunotherapy (SIT) safety has been well documented. However, the prolonged late side effects in patients who terminated SIT several years previously have been reported on in only a limited number of studies. The aim of this study was to perform a 20-year post-SIT observational evaluation for the assessment of any manifestation of serious immunological disease.

MATERIALS AND METHODS

In total, 1,144 patients (521 women and 623 men), with a mean age of 22.8 ± 16.9 years (at the moment of SIT completion) and who had atopic bronchial asthma and/or allergic rhinitis, were observed 20 years after immunotherapy. New neoplastic and autoimmune disease cases were monitored. The SIT group was compared to a control group consisting of 1,154 allergic patients who had never received SIT and had only had symptomatic treatment.

RESULTS

There was an inverse association between SIT treatment and the prevalence of new chronic myeloid leukemia and chronic lymphoblastic leukemia cases (OR 0.32, 95% CI 0.18-0.81 and OR 0.58, CI 0.44-0.78, respectively). In other neoplastic diseases, however, prevalences similar to those observed in the control group were confirmed. There were also no significant differences in the autoimmune disease prevalence between the analyzed groups.

CONCLUSION

The results of this long-term observational study indicate a lack of a significant prevalence for new instances of neoplastic and autoimmune diseases, which suggests that SIT in the long term is indeed safe.

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.

The pathologic and clinical intersection of atopic and autoimmune disease

Hypersensitivity reactions of the immune system have been broadly categorized into the atopic and autoimmune depending on whether the antigen triggering the reaction is endogenous (or self) or exogenous, the types of cellular and humoral components involved, and the clinical symptoms. Research into the pathophysiology of the resultant disease states has focused on a dichotomy between Th1 and Th2 T helper lymphocytes thought to govern autoimmune and atopic disease, respectively. Recent discoveries, however, have served to dispute this paradigm and have provided additional insight into the roles of Th17 cells, B-lymphocytes and T regulatory cells as well as the considerable communication and commonalities between the complex signaling pathways. Furthermore, clinical studies have served to challenge the idea that the presence of atopy and autoimmunity are mutually exclusive states. Finally, application of recent approaches to treatment-biologic targeted therapy in autoimmunity and induction of immune tolerance in atopic disease--to both disease states have shown mixed but promising results.