Comorbid allergic rhinitis and asthma: important clinical considerations

Clinical and Immunological Features of Bronchial Asthma Comorbid Chronic Urticaria: A Retrospective Study

INTRODUCTION

Asthma and chronic urticaria (CU) are two high prevalent diseases and often coexist. The underlying relationship and potential immunological mechanism between the two diseases are still unclear. The objective of this study was to investigate the clinical and immunological feature of asthma comorbid with CU.

METHODS

A retrospective study was conducted. Fifty patients with asthma comorbid CU, 50 patients with asthma, and 50 patients with CU alone were included. Age and sex of the patients enrolled were matched. Data of demographic characteristics, clinical manifestations including disease severity (frequency of symptoms, age of onset, disease duration, symptom score, complication with allergic rhinitis) as well as serum immunological index including total IgE (tIgE), allergen-specific IgE (sIgE), and food-specific IgG4 (FS-IgG4), were collected and analyzed.

RESULTS

No significant differences in the frequency of symptoms, age of onset, and disease duration were found among the three groups. The score of asthma control test (ACT) in patients with asthma comorbid CU was significantly lower than that of asthma (p = 0.005); however, compared with patients with CU, the 7-day urticaria activity score (UAS7) of patients with asthma comorbid CU did not show obvious differences. Immunological index showed that the positive rates of tIgE, house dust mite (HDM)-sIgE, and FS-IgG4 were different among the three groups (p < 0.05). Patients with asthma comorbid CU had the highest rate of positive tIgE, moderate and severe positive sIgE to HDM. Egg-specific IgG4 (egg-sIgG4) had the highest positive rate in all groups. Patients of asthma comorbid CU obtained the highest rate of severe positive of egg-sIgG4.

CONCLUSION

Our results demonstrated that patients with asthma comorbid CU have lower control level of asthma symptoms, higher tIgE and HDM-sIgE level, and highest rate of severe positive egg-sIgG4. These results indicate that comorbidity of CU in asthma obviously increases the severity of allergens.

Decoding the genetic landscape of allergic rhinitis: a comprehensive network analysis revealing key genes and potential therapeutic targets

BACKGROUND

Allergic Rhinitis (AR), an inflammatory affliction impacting the upper respiratory tract, has been registering a substantial surge in incidence across the globe.

METHODS

We embarked on examination of differentially expressed genes (DEGs) and the Weighted Gene Co-Expression Network Analysis (WGCNA). With this armory of genes identified, we engaged the tools of Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). Our study continued with the establishment of a protein-protein interaction (PPI) network and the application of LASSO regression. Finally, we leveraged a docking model to elucidate potential drug-gene interactions involving these key genes.

RESULTS

Through WGCNA and different express genes screening, PPI network was performed, identifying top 20 key genes, including CD44, CD69, CD274. LASSO regression identified three independent factors, STARD5, CST1, and CHAC1, that were significantly associated with AR. A predictive model was developed with an AUC value over 0.75. Also, 105 potential therapeutic agents were discovered, including Fluorouracil, Cyclophosphamide, Doxorubicin, and Hydrocortisone, offering promising therapeutic strategies for AR.

CONCLUSION

By fuzing DEGs with key genes derived from WGCNA, this study has illuminated a comprehensive network of gene interactions involved in the pathogenesis of AR, paving the way for future biomarker and therapeutic target discovery in AR.

Clinical efficacy and safety study of Loratadine combined with glucocorticoid nasal spray in the treatment of pediatric bronchial asthma with seasonal allergic rhinitis

OBJECTIVE

To investigate the clinical efficacy and safety of Loratadine combined with Glucocorticoid nasal spray in the treatment of pediatric bronchial asthma with seasonal allergic rhinitis.

METHODS

A total of 100 pediatric patients with moderate to severe bronchial asthma and seasonal allergic rhinitis admitted to our hospital between January 2020 and January 2023 were included in this study. All patients met the complete inclusion and exclusion criteria. Based on different treatment interventions, they were divided into the control group (n = 50) and the observation group (n = 50). Patients in the control group received treatment with glucocorticoid nasal spray, while patients in the observation group received combined intervention with Loratadine in addition to the treatment received by the control group. The clinical treatment outcomes, incidence of adverse reactions, as well as the scores of nasal symptoms, asthma control, and peak expiratory flow rates at different treatment time points (baseline, T1: 30 days after treatment, T2: 60 days after treatment, T3: 90 days after treatment) were compared between the two groups. The combined treatment of Loratadine with Glucocorticoid nasal spray demonstrates significant clinical efficacy in the treatment of pediatric bronchial asthma with seasonal allergic rhinitis. It further promotes the recovery of peak expiratory flow rates, improves symptoms of rhinitis and asthma in pediatric patients. Importantly, the application of this combined treatment does not increase the risk of adverse reactions in pediatric patients, indicating its high safety profile. This treatment approach is worthy of clinical application and further promotion.

A Novel Quality Control Strategy for the Preparation of High-Quality Recombinant Allergens in Escherichia coli: A Case Study of Der f 2

INTRODUCTION

Recombinant allergens produced by Escherichia coli (E. coli) system play an important role in the component-resolved diagnostics of allergy and vaccine development. However, incorrect folding of recombinant allergens may affect their application. Therefore, it is very important to monitor the correct folding of recombinant allergens. Currently, there is still a lack of a quality control strategy to solve this problem. In this study, a mite allergen, Der f 2, was taken as an example to establish a novel quality control strategy, which was based on chromatography to isolate the allergen, and on enzyme-linked immunosorbent assay to verify the IgE reactivity of the isolated allergen.

METHODS

The nucleotide sequence encoding Der f 2 was codon-optimized and cloned into pET-28a (+) plasmid. Best conditions for the expression of Der f 2 in E. coli were sought. The inclusion body of Der f 2 was denatured and purified by nickel affinity chromatography. Refolding processes were compared using glutathione redox system. The fully and partially folded proteins were separated by anion exchange chromatography, and the IgE reactivity of the isolated proteins was verified by indirect enzyme-linked immunosorbent assay.

RESULTS

An optimized 387 bp segment of the Der f 2 coding gene was successfully expressed in E. coli. Best induction conditions included preinduction bacterial density with absorbance value at 600 nm was 0.6, 1 mM isopropyl beta-d-thiogalactopyranoside at 28°C for 4 h. The Der f 2 protein after refolding was separated by chromatography and two fractions were obtained. The first fraction was identified as monomer protein and the second as aggregate by size-exclusion chromatography. Indirect enzyme-linked immunosorbent assay also confirmed that the first fraction showed higher IgE reactivity.

CONCLUSION

In this study, a novel quality control strategy based on chromatographic separation and IgE reactivity monitoring was established in the case of mite Der f 2, which systematically evaluated the effectiveness of multiple preparation methods for the first time. It is faster and more convenient when compared with the existing methods such as size-exclusion chromatography. This strategy laid a foundation for the stable application of recombinant allergens produced by E. coli in component-resolved diagnostics and the development of molecular vaccines in the future.

Methylation-driven mechanisms of allergic rhinitis during pollen and non-pollen seasons using integrated bioinformatics analysis

Background

Allergic rhinitis (AR) is a widespread allergic airway disease that results from a complex interplay between genetic and environmental factors and affects approximately 10%-40% of the global population. Pollen is a common allergen, and exposure to pollen can cause epigenetic changes. However, the mechanism underlying pollen-induced DNA methylation changes and their potential effects on the allergic march are still unclear. The purpose of this study was to explore the methylation-driven mechanisms of AR during the pollen and non-pollen seasons using bioinformatics analysis and to investigate their relationship with asthma.

Methods

We downloaded DNA methylation and gene expression data from the GEO database (GSE50387: GSE50222, GSE50101) and identified differentially methylated positions (DMPs) and differentially expressed genes (DEGs) during the pollen and non-pollen seasons using the CHAMP and limma packages. Through correlation analysis, we identified methylation-driven genes and performed pathway enrichment analysis to annotate their functions. We incorporated external data on AR combined with asthma (GSE101720) for analysis to identify key CpGs that promote the transformation of AR to asthma. We also utilized external data on olive pollen allergy (GSE54522) for analysis to validate the methylation-driven genes. Weighted correlation network analysis (WGCNA) was employed to identify gene modules significantly correlated with pollen allergy. We extracted genes related to the key methylation-driven gene ZNF667-AS1 from the significant module and performed pathway intelligent clustering using KOBAS-i. We also utilized gene set enrichment analysis to explore the potential function of ZNF667-AS1.

Results

We identified 20 and 24 CpG-Gene pairings during the pollen and non-pollen seasons. After incorporating external data from GSE101720, we found that ZNF667-AS1 is a key gene that may facilitate the transformation of AR into asthma during the pollen season. This finding was further validated in another external dataset, GSE54522, which is associated with pollen allergy. WGCNA identified 17 modules, among which the blue module showed significant correlation with allergies. ZNF667-AS1 was located in the blue module. We performed pathway analysis on the genes correlated with ZNF667-AS1 extracted from the blue module and identified a prominent cluster of pathways in the KOBAS-i results, including Toll-like receptor (TLR) family, MyD88, MAPK, and oxidative stress. Gene set enrichment analysis around cg05508084 (paired with ZNF667-AS1) also indicated its potential involvement in initiating and modulating allergic inflammation from the perspective of TLR and MAPK signaling.

Conclusion

We identified methylation-driven genes and their related pathways during the pollen and non-pollen seasons in patients with AR and identified key CpGs that promote the transformation of AR into asthma due to pollen exposure. This study provides new insights into the underlying molecular mechanisms of the transformation of AR to asthma.

Identification of diagnostic signature, molecular subtypes, and potential drugs in allergic rhinitis based on an inflammatory response gene set

Background

Rhinitis is a complex condition characterized by various subtypes, including allergic rhinitis (AR), which involves inflammatory reactions. The objective of this research was to identify crucial genes associated with inflammatory response that are relevant for the treatment and diagnosis of AR.

Methods

We acquired the AR-related expression datasets (GSE75011 and GSE50223) from the Gene Expression Omnibus (GEO) database. In GSE75011, we compared the gene expression profiles between the HC and AR groups and identified differentially expressed genes (DEGs). By intersecting these DEGs with inflammatory response-related genes (IRGGs), resulting in the identification of differentially expressed inflammatory response-related genes (DIRRGs). Afterwards, we utilized the protein-protein interaction (PPI) network, machine learning algorithms, namely least absolute shrinkage and selection operator (LASSO) regression and random forest, to identify the signature markers. We employed a nomogram to evaluate the diagnostic effectiveness of the method, which has been confirmed through validation using GSE50223. qRT-PCR was used to confirm the expression of diagnostic genes in clinical samples. In addition, a consensus clustering method was employed to categorize patients with AR. Subsequently, extensive investigation was conducted to explore the discrepancies in gene expression, enriched functions and pathways, as well as potential therapeutic drugs among these distinct subtypes.

Results

A total of 22 DIRRGs were acquired, which participated in pathways including chemokine and TNF signaling pathway. Additionally, machine learning algorithms identified NFKBIA, HIF1A, MYC, and CCRL2 as signature genes associated with AR's inflammatory response, indicating their potential as AR biomarkers. The nomogram based on feature genes could offer clinical benefits to AR patients. We discovered two molecular subtypes, C1 and C2, and observed that the C2 subtype exhibited activation of immune- and inflammation-related pathways.

Conclusions

NFKBIA, HIF1A, MYC, and CCRL2 are the key genes involved in the inflammatory response and have the strongest association with the advancement of disease in AR. The proposed molecular subgroups could provide fresh insights for personalized treatment of AR.

Association of LOX gene G473A polymorphism with the occurrence of allergic rhinitis and efficacy of montelukast sodium in children

Allergic rhinitis (AR) is very common in adolescents, and current treatment options are complex and unsatisfactory. The objective of this study was to analyze the association of lysyl oxidase (LOX) gene G473A polymorphism with susceptibility to AR in children. In addition, we analyzed the therapeutic effect of montelukast sodium on AR. Forty-five children with AR (research group, 8.16±2.88 years old) and 51 healthy children (control group, 8.22±3.87 years old) during the same period were selected. The LOX gene G473A polymorphism was detected with polymerase chain reaction (PCR)-restriction fragment length polymorphism method. The effect of G473A polymorphism in the occurrence of AR was assessed by logistic regression analysis. In addition, the levels of C-reactive protein (CRP), Interleukin (IL-6), and IL-8 were measured to observe the relationship between G473A polymorphism and inflammatory factors. Finally, montelukast sodium was given to children with AR to investigate the effect of G473A polymorphism on clinical outcomes. The number of G473A polymorphisms in the research group was not significantly different from the control group for GA-type (P = 0.521). However, the number of GG-type polymorphisms was less while the number of type AA was more than the control group (P = 0.044 and 0.046). Children carrying the AA gene had an approximately 4-fold increased risk of AR, while those carrying the GG gene had a decreased risk (P < 0.001). Moreover, children carrying the GG gene had lower levels of CRP, IL-6, and IL-8 and better clinical outcomes, while those carrying the AA gene had higher levels of inflammatory factors and worse outcomes (P<0.05). LOX gene G473A polymorphism is closely associated with AR pathogenesis and may have an important research value in antagonizing the therapeutic effect of montelukast sodium.

Mast Cells in Upper and Lower Airway Diseases: Sentinels in the Front Line

Mast cells (MCs) are fascinating cells of the innate immune system involved not only in allergic reaction but also in tissue homeostasis, response to infection, wound healing, protection against kidney injury, the effects of pollution and, in some circumstances, cancer. Indeed, exploring their role in respiratory allergic diseases would give us, perhaps, novel therapy targets. Based on this, there is currently a great demand for therapeutic regimens to enfeeble the damaging impact of MCs in these pathological conditions. Several strategies can accomplish this at different levels in response to MC activation, including targeting individual mediators released by MCs, blockade of receptors for MC-released compounds, inhibition of MC activation, limiting mast cell growth, or inducing mast cell apoptosis. The current work focuses on and summarizes the mast cells' role in pathogenesis and as a personalized treatment target in allergic rhinitis and asthma; even these supposed treatments are still at the preclinical stage.

Clarifying the effect of gut microbiota on allergic conjunctivitis risk is instrumental for predictive, preventive, and personalized medicine: a Mendelian randomization analysis

Background

Allergic conjunctivitis is an ocular immune disease which affects the conjunctiva, eyelids, and cornea. Growing evidence implicates the gut microbiota in balancing and modulating immunity response, and in the pathogenesis of allergic disease. As a result, gut microbial imbalance could be a useful indicator for allergic conjunctivitis. From the perspective of predictive, preventive, and personalized medicine (PPPM), clarifying the role of gut microbial imbalance in the development of allergic conjunctivitis could provide a window of opportunity for primary prediction, targeted prevention, and personalized treatment of the disease.

Working hypothesis and methodology

In our study, we hypothesized that individuals with microbial dysbiosis may be more susceptible to allergic conjunctivitis due to an increased inflammatory response. To verify the working hypothesis, our analysis selected genetic variants linked with gut microbiota features (N = 18,340) and allergic conjunctivitis (4513 cases, 649,376 controls) from genome-wide association studies. The inverse-variance weighted (IVW) estimate, Mendelian randomization (MR)-Egger, weighted median estimator, maximum likelihood estimator (MLE), and MR robust adjusted profile score (MR.RAPS) were employed to analyze the impact of gut microbiota on the risk of allergic conjunctivitis and identify allergic conjunctivitis-related gut microbes. Ultimately, these findings may enable the identification of individuals at risk of allergic conjunctivitis through screening of gut microbial imbalances, and allow for new targeted prevention and personalized treatment strategies.

Results

Genetic liability to Ruminococcaceae_UCG_002 (OR, 0.83; 95% CI, 0.70-0.99; P = 4.04×10^-2), Holdemanella (OR, 0.78; 95% CI, 0.64-0.96; P = 2.04×10^-2), Catenibacterium (OR, 0.69; 95% CI, 0.56-0.86; P = 1.09×10^-3), Senegalimassilia (OR, 0.71; 95% CI, 0.55-0.93; P = 1.23×10^-2) genus were associated with a low risk of allergic conjunctivitis with IVW. Besides, we found suggestive associations of a genetic-driven increase in the Oscillospira (OR, 1.41; 95% CI, 1.00-2.00; P = 4.63×10^-2) genus with a higher risk of allergic conjunctivitis. Moreover, MLE and MR.RAPS show consistent results with IVW after further validation and strengthened confidence in the true causal associations. No heterogeneity and pleiotropy was detected.

Conclusions

Our study suggests that gut microbiota may play a causal role in the development of allergic conjunctivitis and provides new insights into the microbiota-mediated mechanism of the disease. Gut microbiota may serve as a target for future predictive diagnostics, targeted prevention, and individualized therapy in allergic conjunctivitis, facilitating the transition from reactive medical services to PPPM in the management of the disease.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-023-00321-9.

Anatomical and histopathological approaches to asthma phenotyping

Asthma is typically characterized by variable respiratory symptoms and airflow limitation. Along with the pathophysiology and symptoms are immunological and inflammatory processes. The last decades research has revealed that the immunology of asthma is highly heterogeneous. This has clinical consequences and identification of immunological phenotypes is currently used to guide biological treatment. The focus of this review is on another dimension of asthma diversity, namely anatomical heterogeneity. Immunopathological alterations may go beyond the central airways to also involve the distal airways, the alveolar parenchyma, and pulmonary vessels. Also, extrapulmonary tissues are affected. The anatomical distribution of inflammation in asthma has remained relatively poorly discussed despite its potential implication on both clinical presentation and response to treatment. There is today evidence that a significant proportion of the asthma patients has small airway disease with type 2 immunity, eosinophilia and smooth muscle infiltration of mast cells. The small airways in asthma are also subjected to remodelling, constriction, and luminal plugging, events that are likely to contribute to the elevated distal airway resistance seen in some patients. In cases when the inflammation extends into the alveolar parenchyma alveolar FCER1-high mast cells, eosinophilia, type 2 immunity and activated alveolar macrophages, together with modest interstitial remodelling, create a complex immunopathological picture. Importantly, the distal lung inflammation in asthma can be pharmacologically targeted by use of inhalers with more distal drug deposition. Biological treatments, which are readily distributed to the distal lung, may also be beneficial in eligible patients with more severe and anatomically widespread disease.

Nerve growth factor causes epinephrine release dysfunction by regulating phenotype alterations and the function of adrenal medullary chromaffin cells in mice with allergic rhinitis

The presence of allergic rhinitis (AR) is an increased risk factor for the occurrence of bronchial asthma (BA). Nerve growth factor (NGF), in addition to its key role in the development and differentiation of neurons, may also be an important inflammatory factor in AR and BA. However, the pathogenesis of the progression of AR to BA remains to be elucidated. The present study aimed to investigate the ability of NGF to mediate nasobronchial interactions and explore possible underlying molecular mechanisms. In the present study, an AR mouse model was established and histology of nasal mucosa tissue injury was determined. The level of phenylethanolamine N‑methyl transferase in adrenal medulla was determined by immunofluorescence. Primary adrenal medullary chromaffin cells (AMCCs) were isolated and cultured from the adrenal medulla of mice. The expression levels of synaptophysin (SYP), STAT1, JAK1, p38 and ERK in NGF‑treated and untreated AMCCs were detected by reverse‑transcription‑quantitative PCR and western blotting. The epinephrine (EPI) and norepinephrine (NE) concentrations were measured by ELISA. It was found that the expression of SYP in AMCCs was enhanced in the presence of NGF, whereas, the concentration of EPI decreased significantly under the same conditions. Furthermore, NGF mediated the phenotypic and functional changes of AMCCs, resulting in decreased EPI secretion via JAK1/STAT1, p38 and ERK signaling. In conclusion, these findings could provide novel evidence for the role of NGF in regulating neuroendocrine mechanisms.