Anti-IL-5 treatment reduces deposition of ECM proteins in the bronchial subepithelial basement membrane of mild atopic asthmatics

Biologics and airway remodeling in asthma: early, late, and potential preventive effects

Although airway remodeling in severe and/or fatal asthma is stil considered irreversible, its individual components as a cause of clinical symptoms and/or lung function changes remain largely unknown. While inhaled glucocorticoids have not consistently been shown to affect airway remodeling, biologics targeting specific pathways of airway inflammation have been shown to improve lung function, mucus plugging, and airway structural changes that can exceed those seen with glucocorticoids. This superiority of biologic treatment, which cannot be solely explained by insufficient doses or limited durations of glucocorticoid therapies, needs to be further explored. For this field of research, we propose a novel classification of the potential effects of biologics on airway remodeling into three temporal effects: early effects (days to weeks, primarily modulating inflammatory processes), late effects (months to years, predominantly affecting structural changes), and potential preventive effects (outcomes of early treatment with biologics). For the identification of potential preventive effects of biologics, we call for studies exploring the impact of early biological treatment on airway remodeling in patients with moderate-to-severe asthma, which should be accompanied by a long-term evaluation of clinical parameters, biomarkers, treatment burden, and socioeconomic implications.

Therapeutic potential of a novel hybrid protein: Mitigating allergy and airway remodeling in chronic asthma models induced by Dermatophagoides pteronyssinus

BACKGROUND

The house-dust mite Dermatophagoides pteronyssinus is a key trigger of allergic asthma. Therefore, it is essential to develop new vaccines that can alter inflammatory processes and airway remodeling. The goal of this study was to test the hypoallergenic and immunogenic characteristics of the hypoallergen rDer p 2231 in a murine model of chronic asthma induced by D. pteronyssinus.

METHODS

For this, we measured the levels of IgE, IgG1, IgG2a, and cytokines produced by mice receiving the rDer p 2231 protein. Histopathological parameters of the chronic inflammatory response were also investigated by assessing inflammation and airway remodeling.

RESULTS

rDer p 2231 given as a therapeutic vaccine, led to a reduction in the production of IgE, eosinophils, and neutrophils, a lower activity of eosinophilic peroxidase in the airways, and an increase in the production of IgG1 and IgG2a antibodies. IgG antibodies blocked IgE binding to parental allergens in sera from atopic patients. Splenocytes, BALF, and lung from mice treated with rDer p 2231 secreted higher levels of Th1 and regulatory cytokines, as well as reduced levels of Th2 cytokines. Histopathological investigation of the lower airways demonstrated reductions in the thickness of the bronchiolar smooth muscle layer, in the subepithelial fibrosis, and in the goblet cells hyperplasia.

CONCLUSIONS

Our preclinical studies suggest that rDer p 2231 is a promising candidate for the treatment of D. pteronyssinus allergy, as the hypoallergen has demonstrated the ability to reduce IgE production, induce specific blocking antibodies, restore and balance Th1/Th2 immune responses, and significantly reduce airway remodeling factors. However, additional clinical studies are needed to more accurately assess the efficacy and safety of rDer p 2231 as a vaccine against D. pteronyssinus-induced allergy.

Identifying super-responders: A review of the road to asthma remission

Asthma is a chronic respiratory disease marked by heterogeneity and variable clinical outcomes. Recent therapeutic advances have highlighted patients achieving optimal outcomes, termed "remission" or "super-response." This review evaluates the various definitions of these terms and explores how disease burden impedes the attainment of remission. We assessed multiple studies, including a recent systematic review and meta-analysis, on biologic treatments for asthma remission. Our review highlights that type 2 inflammation may be the strongest predictor of biologic response. Key comorbidities (eg, obesity and mood disorders) and behavioral factors (eg, poor adherence, improper inhalation technique, and smoking) were identified as dominant traits limiting remission. In addition, asthma burden and longer disease duration significantly restrict the potential for remission in patients with severe asthma under the current treatment paradigm. We review the potential for a "predict-and-prevent" approach, which focuses on early identification of high-risk patients with type 2 inflammation and aggressive treatment to improve long-term asthma outcomes. In conclusion, this scoping review highlights the following unmet needs in asthma remission: (1) a harmonized global definition, with better defined lung function parameters; (2) integration of nonbiologic therapies into remission strategies; and (3) a clinical trial of early biologic intervention in patients with remission-prone, very type 2-high, moderately severe asthma with clinical remission as a predefined primary end point.

Interleukin-5 as a pleiotropic cytokine orchestrating airway type 2 inflammation: Effects on and beyond eosinophils

Interleukin (IL)-5 is the key cytokine in the maturation, activation, proliferation, migration and survival of eosinophils, which are key effector cells in many upper and lower airway diseases. Through its effects on eosinophils, IL-5 indirectly contributes to various pathophysiological processes including tissue damage, repair and remodelling. Understanding the importance of IL-5 in eosinophil-associated diseases led to the development of anti-IL-5 therapies, which provide clinical benefits across a range of conditions. However, recent evidence suggests that eosinophil-depletion alone may not account for all of the therapeutic effects of anti-IL-5 therapy and that IL-5 may also contribute to disease independently of its effects on eosinophils. Indeed, evidence from ex vivo studies and targeted therapy in vivo demonstrates that IL-5 and its inhibition affects a much broader range of cells beyond eosinophils, including epithelial cells, plasma cells, mast cells, basophils, neutrophils, type 2 innate lymphoid cells, T regulatory cells and fibroblasts. This review will provide an update on the evidence supporting the breadth of IL-5 biology relevant to disease pathogenesis beyond eosinophil-associated inflammation, where there is a need for additional insight, and the clinical implications of a more central role of IL-5 in type 2 inflammation.

CSF1-dependent macrophage support matrisome and epithelial stress-induced keratin remodeling in Eosinophilic esophagitis

Atopic diseases such as Eosinophilic Esophagitis (EoE) often progress into fibrosis (FS-EoE), compromising organ function with limited targeted treatment options. Mechanistic understanding of FS-EoE progression is confounded by the lack of preclinical models and the heavy focus of research on eosinophils themselves. We found that macrophage accumulation precedes esophageal fibrosis in FS-EoE patients. We developed a FS-EoE model via chronic administration of oxazalone allergen, in a transgenic mouse over-expressing esophageal epithelial hIL-5 (L2-IL5OXA). These mice display striking histopathologic features congruent with that found in FS-EoE patients. Unbiased proteomic analysis, using a unique extracellular-matrix (ECM) focused technique, identified an inflammation-reactive provisional basal lamina membrane signature and this was validated in two independent EoE patient RNA-sequencing/proteomic cohorts, supporting model significance. A wound healing signature was also observed involving hemostasis-associated molecules previously unnoted in EoE. We further identified the ECM glycoprotein, Tenascin-C (TNC), and the stress-responsive keratin-16 (KRT16) as IL-4 and IL-13 responsive mediators, acting as biomarkers of FS-EoE. To mechanistically address how the immune infiltrate shapes FS-EoE progression, we phenotyped the major immune cell subsets that coalesce with fibrosis in both the L2-IL5OXA mice and in FS-EoE patients. We found that macrophage are required for matrisome and cytoskeletal remodeling. Importantly, we show that macrophage accumulation precedes esophageal fibrosis and provide a novel therapeutic target in FS-EoE as their depletion with anti-CSF1 attenuated reactive matrisome and cytoskeletal changes. Thus, macrophage-based treatments and the exploration of TNC and KRT16 as biomarkers may provide novel therapeutic options for patients with fibrostenosis.

Airway Remodeling in Asthma: Mechanisms, Diagnosis, Treatment, and Future Directions

Airway remodeling (AR) with chronic inflammation, are key features in asthma pathogenesis. AR characterized by structural changes in the bronchial wall is associated with a specific asthma phenotype with poor clinical outcomes, impaired lung function and reduced treatment response. Most studies focus on the role of inflammation, while understanding the mechanisms driving AR is crucial for developing disease-modifying therapeutic strategies. This review paper summarizes current knowledge on the mechanisms underlying AR, diagnostic tools, and therapeutic approaches. Mechanisms explored include the role of the resident cells and the inflammatory cascade in AR. Diagnostic methods such as bronchial biopsy, lung function testing, imaging, and possible biomarkers are described. The effectiveness on AR of different treatments of asthma including corticosteroids, leukotriene modifiers, bronchodilators, macrolides, biologics, and bronchial thermoplasty is discussed, as well as other possible therapeutic options. AR poses a significant challenge in asthma management, contributing to disease severity and treatment resistance. Current therapeutic approaches target mostly airway inflammation rather than smooth muscle cell dysfunction and showed limited benefits on AR. Future research should focus more on investigating the mechanisms involved in AR to identify novel therapeutic targets and to develop new effective treatments able to prevent irreversible structural changes and improve long-term asthma outcomes.

Elevated Proportions of Circulating CXCR5+ Follicular Helper T Cells Reflect the Presence of Airway Obstruction in Asthma

Materials and Methods

Using flow cytometry, we identified and quantified Group 2 innate lymphocytes, T helper 2 cells, follicular helper T cells, and T helper 17 cells in peripheral blood samples from 49 individuals with asthma. We then conducted cross-sectional analyses to assess relationships between levels of these immune cells and lung function parameters, including the percentage predicted forced expiratory volume in 1 s (%FEV1). We also examined correlations between the proportions of immune cells and type 2 biomarkers.

Results

Proportions of CXCR5+ follicular helper T cells in human peripheral blood, as opposed to Group 2 innate lymphoid cells (ILC2) or T helper 2 cells, were significantly higher in cases with %FEV1 < 80% compared to those with %FEV1 ≥ 80%. Further, these proportions correlated negatively with %FEV1 and positively with blood eosinophil counts.

Conclusions

The proportion of circulating follicular helper T cells, but not T helper 2 cells or Group 2 innate lymphoid cells, may reflect the presence of airway obstruction caused by persistent type 2 inflammation.

Increased white blood cell count is associated with an increased demand for unfractionated heparin during veno-arterial extracorporeal oxygenation in lung transplantation

BACKGROUND

This retrospective observational study aimed to examine whether clinical inflammatory parameters were associated with the requirement dosage of unfractionated heparin (UFH) to maintain the range of ACT in veno-arterial extracorporeal membrane oxygenation (V-A ECMO) during lung transplantation surgery.

METHODS

Among all patients who underwent lung transplantation using V-A ECMO from January 2021 to May 2022, 27 patients were included. These patients were divided into two groups based on whether the infusion rate of UFH was increased from the initial infusion rate (7-8 units/kg/h) (increased group, n = 10) or the infusion rate was maintained or decreased (non-increased group, n = 17). The infusion rate was adjusted with an activated clotting time (ACT) target of 160-200 s.

RESULTS

At 1-2 h after starting ECMO, ACT was significantly lower (179.0 (166.5-188.5) versus 224.0 (193.0-242.0) sec, p = 0.006) and white blood cell (WBC) counts were higher in the increased group (12.6 ± 3.3 versus 9.5 ± 4.0 × 103/μL, p = 0.046). The UFH infusion rates were higher in the increased group during the surgery. The cutoff value of WBC count at 1-2 h after starting ECMO for discriminating the need for increasing the UFH dosage was determined as 10.2 × 103/μL (sensitivity 90.0%, specificity 58.8%, area under the curve 0.712) and discrimination of this cut-off value was confirmed as statistically significant (p = 0.018).

CONCLUSION

These data suggested that WBC count was associated with the requirement of an increase in the UFH infusion rate of V-A ECMO during lung transplantation surgery. Further evaluation is necessary to clarify the role of WBC count in determining the optimal UFH dosage.

Biologics in T2 Severe Asthma: Unveiling Different Effectiveness by Real-World Indirect Comparison

Background: Indirect comparison among biologics in severe asthma (SA) is a challenging but desirable goal for clinicians in real life. The aim of the study is to define characteristics of a biologic-treated T2-driven-SA population and to evaluate the effectiveness of biologic treatments in a real-world setting by variation in intra/inter-biologic parameters in an up to 4-year follow-up. Methods: Demographic, clinical, functional, and biological characteristics were evaluated retrospectively in 104 patients recruited until July 2022 at baseline (T0) and over a maximum of 4 years (T4) of biologic therapy (omalizumab/OmaG = 41, from T0 to T4, mepolizumab/MepoG = 26, from T0 to T4, benralizumab/BenraG = 18, from T0 to T2, and dupilumab/DupiG = 19, from T0 to T1). Variations of parameters using means of paired Delta were assessed. Results: At baseline, patients had high prevalence of T2-driven comorbidities, low asthma control test (ACT mean 17.65 ± 4.41), impaired pulmonary function (FEV1 65 ± 18 %pred), frequent exacerbations/year (AEs 3.5 ± 3), and OCS dependence (60%). DupiG had lower T2 biomarkers/comorbidities and AEs, and worse FEV1 (57 ± 19 %pred) compared to other biologics (p < 0.05). All biologics improved ACT, FEV1%, FVC%, AEs rate, and OCS use. FEV1% improved in MepoG and BenraG over the minimal clinically important difference and was sustained over 4 years in OmaG and MepoG. A significant RV reduction in OmaG (T4) and DupiG (T1), and BenraG normalization (T2) of airflow limitation were found. We observed through inter-biologic parameters pair delta variation comparison a significant nocturnal awakenings reduction in BenraG vs. OmaG/MepoG, and neutrophils reduction in BenraG/DupiG vs. OmaG. Conclusions: Indirect comparison among biologics unveils clinical and functional improvements that may mark a different effectiveness. These results may highlight the preference of a single biologic compared to another with regard to specific treatable traits.

IL-5 antagonism reverses priming and activation of eosinophils in severe eosinophilic asthma

Eosinophils are key effector cells mediating airway inflammation and exacerbation in patients with severe eosinophilic asthma. They are present in increased numbers and activation states in the airway mucosa and lumen. Interleukin-5 (IL-5) is the key eosinophil growth factor that is thought to play a role in eosinophil priming and activation. However, the mechanism of these effects is still not fully understood. The anti-IL-5 antibody mepolizumab reduces eosinophil counts in the airway modestly but has a large beneficial effect on the frequency of exacerbations of severe eosinophilic asthma, suggesting that reduction in eosinophil priming and activation is of central mechanistic importance. In this study, we used the therapeutic effect of mepolizumab and single-cell ribonucleic acid sequencing to investigate the mechanism of eosinophil priming and activation by IL-5. We demonstrated that IL-5 is a dominant driver of eosinophil priming and plays multifaceted roles in eosinophil function. It enhances eosinophil responses to other stimulators of migration, survival, and activation by activating phosphatidylinositol-3-kinases, extracellular signal-regulated kinases, and p38 mitogen-activated protein kinases signaling pathways. It also enhances the pro-fibrotic roles of eosinophils in airway remodeling via transforming growth factor-β pathway. These findings provide a mechanistic understanding of eosinophil priming in severe eosinophilic asthma and the therapeutic effect of anti-IL-5 approaches in the disease.

Role of IL-5 in asthma and airway remodelling

Asthma is a common and burdensome chronic inflammatory airway disease that affects both children and adults. One of the main concerns with asthma is the manifestation of irreversible tissue remodelling of the airways due to the chronic inflammatory environment that eventually disrupts the whole structure of the airways. Most people with troublesome asthma are treated with inhaled corticosteroids. However, the development of steroid resistance is a commonly encountered issue, necessitating other treatment options for these patients. Biological therapies are a promising therapeutic approach for people with steroid-resistant asthma. Interleukin 5 is recently gaining a lot of attention as a biological target relevant to the tissue remodelling process. Since IL-5-neutralizing monoclonal antibodies (mepolizumab, reslizumab and benralizumab) are currently available for clinical use, this review aims to revisit the role of IL-5 in asthma pathogenesis at large and airway remodelling in particular, in addition to exploring its role as a target for biological treatments.

Mepolizumab in Severe Pediatric Asthma: Certainties and Doubts through a Single-Center Experience and Review of the Literature

BACKGROUND

Although, in most children with asthma, good symptom control is achieved with a low to moderate dose of inhaled corticosteroids, a small group of patients still experiences frequent symptoms, and even severe exacerbations, impairment of lung function, and reduced quality of life. Some of these subjects with severe asthma require biologic drugs as add-on therapy. In the past decade, numerous monoclonal antibodies have been approved for children or adolescents with severe asthma, in addition to their increasing use in adult asthma. However, the available evidence on how to select the most appropriate biologic based on a single patient's clinical, functional, and laboratory characteristics is still scant, and is insufficient to guide clinicians in the decision-making process of a personalized treatment.

MATERIALS AND METHODS

We report a case series of four patients with severe eosinophilic asthma treated with mepolizumab, an anti-interleukin-5 monoclonal antibody, and review the existing literature on this treatment in children and adolescents.

RESULTS

Our patients, all with blood eosinophilia and elevated fractional exhaled nitric oxide levels, developed poor symptom control despite prolonged treatment with high-dose inhaled corticosteroids plus a second controller, addressing the addition of a biologic drug. In all of them, a 12-month treatment with subcutaneous mepolizumab showed a reduction in the blood eosinophil count and in asthma exacerbations, as well as an improvement on the Asthma Control Test. The results of the literature search focused on the strengths and limitations of the pediatric use of mepolizumab and highlighted the areas worthy of further research.

CONCLUSIONS

Mepolizumab has proven effective in improving symptom control in pediatric patients with severe asthma. Additional well-powered clinical trials will be helpful in developing evidence-based guidelines regarding biologic drugs in the pediatric population.

Eosinophil plasticity and diversity: proceedings of the 2023 International Eosinophil Society Symposium

This issue highlights and details the program and scientific presentations at the International Eosinophil Society's 12th biennial symposium, which was held in Hamilton, Ontario, Canada, in July 2023. The meeting included sessions on regulation of eosinophil development; cell death, stress, and autophagy in eosinophils; local immunity interactions of eosinophils with multiple cell types; eosinophils in host defense; eosinophils and mast cells in gastrointestinal disorders; reciprocal interactions between eosinophils and the microbiome in homeostasis and dysbiosis; and eosinophils in tissue injury and repair and in tumor biology and cancer therapy. There was a mixture of special invited lectures and cutting-edge abstracts on specific aspects of eosinophil science, as well as enlivened pro-con debates on targeting eosinophils with biologics. A major thrust and overarching theme was that eosinophils exhibit remarkable plasticity and heterogeneity in executing their functions both in homeostasis and in pathobiology; there is a new "eo-verse" to understand. We trust that this special volume of the Journal of Leukocyte Biology will be of interest across many disciplines and medical subspecialties in biomedical sciences and demonstrate both the complexity and versatility of the eosinophil in biology and medicine.

The effects of inhaled corticosteroids on healthy airways

BACKGROUND

The effects of inhaled corticosteroids (ICS) on healthy airways are poorly defined.

OBJECTIVES

To delineate the effects of ICS on gene expression in healthy airways, without confounding caused by changes in disease-related genes and disease-related alterations in ICS responsiveness.

METHODS

Randomized open-label bronchoscopy study of high-dose ICS therapy in 30 healthy adult volunteers randomized 2:1 to (i) fluticasone propionate 500 mcg bd daily or (ii) no treatment, for 4 weeks. Laboratory staff were blinded to allocation. Biopsies and brushings were analysed by immunohistochemistry, bulk RNA sequencing, DNA methylation array and metagenomics.

RESULTS

ICS induced small between-group differences in blood and lamina propria eosinophil numbers, but not in other immunopathological features, blood neutrophils, FeNO, FEV1, microbiome or DNA methylation. ICS treatment upregulated 72 genes in brushings and 53 genes in biopsies, and downregulated 82 genes in brushings and 416 genes in biopsies. The most downregulated genes in both tissues were canonical markers of type-2 inflammation (FCER1A, CPA3, IL33, CLEC10A, SERPINB10 and CCR5), T cell-mediated adaptive immunity (TARP, TRBC1, TRBC2, PTPN22, TRAC, CD2, CD8A, HLA-DQB2, CD96, PTPN7), B-cell immunity (CD20, immunoglobulin heavy and light chains) and innate immunity, including CD48, Hobit, RANTES, Langerin and GFI1. An IL-17-dependent gene signature was not upregulated by ICS.

CONCLUSIONS

In healthy airways, 4-week ICS exposure reduces gene expression related to both innate and adaptive immunity, and reduces markers of type-2 inflammation. This implies that homeostasis in health involves tonic type-2 signalling in the airway mucosa, which is exquisitely sensitive to ICS.

Type 2 severe asthma: pathophysiology and treatment with biologics

INTRODUCTION

The hallmark of most patients with severe asthma is type 2 inflammation, driven by innate and adaptive immune responses leading to either allergic or non-allergic eosinophilic infiltration of airways. The cellular and molecular pathways underlying severe type 2 asthma can be successfully targeted by specific monoclonal antibodies.

AREAS COVERED

This review article provides a concise overview of the pathophysiology of type 2 asthma, followed by an updated appraisal of the mechanisms of action and therapeutic efficacy of currently available biologic treatments used for management of severe type 2 asthma. Therefore, all reported information arises from a wide literature search performed on PubMed.

EXPERT OPINION

The main result of the recent advances in the field of anti-asthma biologic therapies is the implementation of a personalized medicine approach, aimed to achieve clinical remission of severe asthma. Today this accomplishment is made possible by the right choice of the most beneficial biologic drug for the pathologic traits characterizing each patient, including type 2 severe asthma and its comorbidities.

Skin, gut, and lung barrier: Physiological interface and target of intervention for preventing and treating allergic diseases

The epithelial barriers of the skin, gut, and respiratory tract are critical interfaces between the environment and the host, and they orchestrate both homeostatic and pathogenic immune responses. The mechanisms underlying epithelial barrier dysfunction in allergic and inflammatory conditions, such as atopic dermatitis, food allergy, eosinophilic oesophagitis, allergic rhinitis, chronic rhinosinusitis, and asthma, are complex and influenced by the exposome, microbiome, individual genetics, and epigenetics. Here, we review the role of the epithelial barriers of the skin, digestive tract, and airways in maintaining homeostasis, how they influence the occurrence and progression of allergic and inflammatory conditions, how current treatments target the epithelium to improve symptoms of these disorders, and what the unmet needs are in the identification and treatment of epithelial disorders.

The New Paradigm: The Role of Proteins and Triggers in the Evolution of Allergic Asthma

Epithelial barrier damage plays a central role in the development and maintenance of allergic inflammation. Rises in the epithelial barrier permeability of airways alter tissue homeostasis and allow the penetration of allergens and other external agents. Different factors contribute to barrier impairment, such as eosinophilic infiltration and allergen protease action-eosinophilic cationic proteins' effects and allergens' proteolytic activity both contribute significantly to epithelial damage. In the airways, allergen proteases degrade the epithelial junctional proteins, allowing allergen penetration and its uptake by dendritic cells. This increase in allergen-immune system interaction induces the release of alarmins and the activation of type 2 inflammatory pathways, causing or worsening the main symptoms at the skin, bowel, and respiratory levels. We aim to highlight the molecular mechanisms underlying allergenic protease-induced epithelial barrier damage and the role of immune response in allergic asthma onset, maintenance, and progression. Moreover, we will explore potential clinical and radiological biomarkers of airway remodeling in allergic asthma patients.

The Possible Roles of IL-4/IL-13 in the Development of Eosinophil-Predominant Severe Asthma

Bronchial asthma is characterized by airway inflammation, airway hyperresponsiveness, and reversible airway obstruction. Eosinophils contribute to the pathogenesis of airway disease mainly by releasing eosinophil-specific granules, lipid mediators, superoxide anions, and their DNA. Type-2 cytokines such as interleukin (IL)-4 and IL-13 also play roles in the development of bronchial asthma. Among these cytokines, IL-4 is involved in T-cell differentiation, B-cell activation, B-cell differentiation into plasma cells, and the production of immunoglobulin E. Although IL-13 has similar effects to IL-4, IL-13 mainly affects structural cells, such as epithelial cells, smooth muscle cells, and fibroblasts. IL-13 induces the differentiation of goblet cells that produce mucus and induces the airway remodeling, including smooth muscle hypertrophy. IL-4 and IL-13 do not directly activate the effector functions of eosinophils; however, they can induce eosinophilic airway inflammation by upregulating the expression of vascular cell adhesion molecule-1 (for adhesion) and CC chemokine receptor 3 ligands (for migration). Dupilumab, a human anti-IL-4 receptor α monoclonal antibody that inhibits IL-4 and IL-13 signaling, decreases asthma exacerbations and mucus plugs and increases lung function in moderate to severe asthma. In addition, dupilumab is effective for chronic rhinosinusitis with nasal polyps and for atopic dermatitis, and IL-4/IL-13 blocking is expected to suppress allergen sensitization, including transcutaneous sensitization and atopic march.

Airway remodelling in asthma and the epithelium: on the edge of a new era

Asthma is a chronic, heterogeneous disease of the airways, often characterised by structural changes known collectively as airway remodelling. In response to environmental insults, including pathogens, allergens and pollutants, the epithelium can initiate remodelling via an inflammatory cascade involving a variety of mediators that have downstream effects on both structural and immune cells. These mediators include the epithelial cytokines thymic stromal lymphopoietin, interleukin (IL)-33 and IL-25, which facilitate airway remodelling through cross-talk between epithelial cells and fibroblasts, and between mast cells and airway smooth muscle cells, as well as through signalling with immune cells such as macrophages. The epithelium can also initiate airway remodelling independently of inflammation in response to the mechanical stress present during bronchoconstriction. Furthermore, genetic and epigenetic alterations to epithelial components are believed to influence remodelling. Here, we review recent advances in our understanding of the roles of the epithelium and epithelial cytokines in driving airway remodelling, facilitated by developments in genetic sequencing and imaging techniques. We also explore how new and existing therapeutics that target the epithelium and epithelial cytokines could modify airway remodelling.

The airway epithelium: an orchestrator of inflammation, a key structural barrier and a therapeutic target in severe asthma

Asthma is a disease of heterogeneous pathology, typically characterised by excessive inflammatory and bronchoconstrictor responses to the environment. The clinical expression of the disease is a consequence of the interaction between environmental factors and host factors over time, including genetic susceptibility, immune dysregulation and airway remodelling. As a critical interface between the host and the environment, the airway epithelium plays an important role in maintaining homeostasis in the face of environmental challenges. Disruption of epithelial integrity is a key factor contributing to multiple processes underlying asthma pathology. In this review, we first discuss the unmet need in asthma management and provide an overview of the structure and function of the airway epithelium. We then focus on key pathophysiological changes that occur in the airway epithelium, including epithelial barrier disruption, immune hyperreactivity, remodelling, mucus hypersecretion and mucus plugging, highlighting how these processes manifest clinically and how they might be targeted by current and novel therapeutics.

Small airways in asthma: From inflammation and pathophysiology to treatment response

Small airways are characterized as those with an inner diameter less than 2 mm and constitute a major site of pathology and inflammation in asthma disease. It is estimated that small airways dysfunction may occur before the emergence of noticeable symptoms, spirometric abnormalities and imaging findings, thus characterizing them as "the quiet or silent zone" of the lungs. Despite their importance, measuring and quantifying small airways dysfunction presents a considerable challenge due to their inaccessibility in usual functional measurements, primarily due to their size and peripheral localization. Several pulmonary function tests have been proposed for the assessment of the small airways, including impulse oscillometry, nitrogen washout, body plethysmography, as well as imaging methods. Nevertheless, none of these methods has been established as the definitive "gold standard," thus, a combination of them should be used for an effective assessment of the small airways. Widely used asthma treatments seem to also affect several parameters of the small airways. Emerging biologic treatments show promising results in reducing small airways inflammation and remodelling, providing evidence for potential alterations in the disease's progression and outcomes. These novel therapies have implications not only in the clinical aspects of asthma but also in its inflammatory and functional aspects.

Influence of Platelet-Rich Plasma on Recurrent Vesicovaginal Fistula-A Histological and Immunohistochemical Study

Vesicovaginal fistula is a cause of deterioration in the quality of life. It is a communication between the bladder and vagina resulting in the uncontrollable leakage of urine through the vagina. Recently, regenerative methods have been used more frequently, and platelet-rich plasma is one of these methods. The functional properties of platelet-rich plasma are based on the synthesis and secretion of multiple growth factors released after platelet activation. The aim of this study was to investigate how platelet-rich plasma influences the condition of the tissue and the healing ability of the urothelium, vaginal epithelium and tissues surrounding the fistulous canal. The study included eight patients who had undergone the Latzko procedure aimed at closing the vesicovaginal fistula. Samples were collected during primary surgery without platelet-rich plasma and after failed surgery, during a second attempt. The specimens were subjected to histological and immunohistochemical evaluation. The histology demonstrated that in platelet-rich plasma patients, greater vascularization and wider subepithelial mucosa layering was observed. Inflammatory infiltration in the subepithelial layer was increased in platelet-rich plasma patients. No localization differences in growth factor proteins were found in either group, but in platelet-rich plasma-patients, the reactions were stronger. It can be concluded that the use of platelet-rich plasma improves the morphological structure of the injected tissues.

Phytochemicals as treatment for allergic asthma: Therapeutic effects and mechanisms of action

BACKGROUND

Allergic asthma is an inflammatory disease caused by the immune system's reaction to allergens, inflammation and narrowing of the airways, and the production of more than normal mucus. One of the main reasons is an increased production of inflammatory cytokines in the lungs that leads to the appearance of symptoms of asthma, including inflammation and shortness of breath. On the other hand, it has been proven that phytochemicals with their antioxidant and anti-inflammatory properties can be useful in improving allergic asthma.

PURPOSE

Common chemical treatments for allergic asthma include corticosteroids, which have many side effects and temporarily relieve symptoms but are not a cure. Therefore, taking the help of natural compounds to improve the quality of life of asthmatic patients can be a valuable issue that has been evaluated in the present review.

STUDY DESIGN AND METHODS

In this study, three databases (Scopus, PubMed, and Cochrane) with the keywords: allergic asthma, phytochemical, plant, and herb were evaluated. The primary result was 5307 articles. Non-English, repetitive, and review articles were deleted from the study.

RESULTS AND DISCUSSION

Finally, after carefully reading the articles, 102 were included in the study (2006-2022). The results of this review state that phytochemicals suppress the inflammatory pathways via inhibition of inflammatory cytokines production/secretion, genes, and proteins involved in the inflammation process, reducing oxidative stress indicators and symptoms of allergic asthma, such as cough and mucus production in the lungs.

CONCLUSION

With their antioxidant effects, this study concluded that phytochemicals suppress cytokines and other inflammatory indicators and thus can be considered an adjunctive treatment for improving allergic asthma.

Medicine Targeting Epithelial-Mesenchymal Transition to Treat Airway Remodeling and Pulmonary Fibrosis Progression

Objective. Dysregulation of epithelial-mesenchymal transition (EMT) in the airway epithelium is associated with airway remodeling and the progression of pulmonary fibrosis. Many treatments have been shown to inhibit airway remodeling and pulmonary fibrosis progression in asthma and chronic obstructive pulmonary disease (COPD) by regulating EMT and have few side effects. This review aimed to describe the development of airway remodeling through the EMT pathway, as well as the potential therapeutic targets in these pathways. Furthermore, this study aimed to review the current research on drugs to treat airway remodeling and their effects on the EMT pathway. Findings. The dysregulation of EMT was associated with airway remodeling in various respiratory diseases. The cytokines released during inflammation may induce EMT and subsequent airway remodeling. Various drugs, including herbal formulations, specific herbal compounds, cytokines, amino acid or protein inhibitors, microRNAs, and vitamins, may suppress airway remodeling by inhibiting EMT-related pathways.

Isthmin-1 attenuates allergic Asthma by stimulating adiponectin expression and alveolar macrophage efferocytosis in mice

BACKGROUND

Allergic asthma is a common respiratory disease that significantly impacts human health. Through in silico analysis of human lung RNASeq, we found that asthmatic lungs display lower levels of Isthmin-1 (ISM1) expression than healthy lungs. ISM1 is an endogenous anti-inflammatory protein that is highly expressed in mouse lungs and bronchial epithelial cells, playing a crucial role in maintaining lung homeostasis. However, how ISM1 influences asthma remains unclear. This study aims to investigate the potential involvement of ISM1 in allergic airway inflammation and uncover the underlying mechanisms.

METHODS

We investigated the pivotal role of ISM1 in airway inflammation using an ISM1 knockout mouse line (ISM1-/-) and challenged them with house dust mite (HDM) extract to induce allergic-like airway/lung inflammation. To examine the impact of ISM1 deficiency, we analyzed the infiltration of immune cells into the lungs and cytokine levels in bronchoalveolar lavage fluid (BALF) using flow cytometry and multiplex ELISA, respectively. Furthermore, we examined the therapeutic potential of ISM1 by administering recombinant ISM1 (rISM1) via the intratracheal route to rescue the effects of ISM1 reduction in HDM-challenged mice. RNA-Seq, western blot, and fluorescence microscopy techniques were subsequently used to elucidate the underlying mechanisms.

RESULTS

ISM1-/- mice showed a pronounced worsening of allergic airway inflammation and hyperresponsiveness upon HDM challenge. The heightened inflammation in ISM1-/- mice correlated with enhanced lung cell necroptosis, as indicated by higher pMLKL expression. Intratracheal delivery of rISM1 significantly reduced the number of eosinophils in BALF and goblet cell hyperplasia. Mechanistically, ISM1 stimulates adiponectin secretion by type 2 alveolar epithelial cells partially through the GRP78 receptor and enhances adiponectin-facilitated apoptotic cell clearance via alveolar macrophage efferocytosis. Reduced adiponectin expression under ISM1 deficiency also contributed to intensified necroptosis, prolonged inflammation, and heightened severity of airway hyperresponsiveness.

CONCLUSIONS

This study revealed for the first time that ISM1 functions to restrain airway hyperresponsiveness to HDM-triggered allergic-like airway/lung inflammation in mice, consistent with its persistent downregulation in human asthma. Direct administration of rISM1 into the airway alleviates airway inflammation and promotes immune cell clearance, likely by stimulating airway adiponectin production. These findings suggest that ISM1 has therapeutic potential for allergic asthma.

Developments in the Management of Severe Asthma in Children and Adolescents: Focus on Dupilumab and Tezepelumab

Severe asthma in children and adolescents exerts a substantial health, financial, and societal burden. Severe asthma is a heterogeneous condition with multiple clinical phenotypes and underlying inflammatory patterns that might be different in individual patients. Various add-on treatments have been developed to treat severe asthma, including monoclonal antibodies (biologics) targeting inflammatory mediators. Biologics that are currently approved to treat children (≥ 6 years of age) or adolescents (≥ 12 years of age) with severe asthma include: anti-immunoglobulin E (omalizumab), anti-interleukin (IL)-5 (mepolizumab), anti-IL5 receptor (benralizumab), anti-IL4/IL13 receptor (dupilumab), and antithymic stromal lymphopoietin (TSLP) (tezepelumab). However, access to these targeted treatments varies across countries and relies on few and crude indicators. There is a need for better treatment stratification to guide which children might benefit from these treatments. In this narrative review we will assess the most recent developments in the treatment of severe pediatric asthma, as well as potential biomarkers to assess treatment efficacy for this patient population.

Dysfunctional mucociliary clearance in asthma and airway remodeling - New insights into an old topic

Bronchial asthma is a heterogeneous respiratory condition characterized by chronic airway inflammation, airway hyperresponsiveness and airway structural changes (known as remodeling). The clinical symptoms can be evoked by (non)specific triggers, and their intensity varies over time. In the past, treatment was mainly focusing on symptoms' alleviation; in contrast modern treatment strategies target the underlying inflammation, even during asymptomatic periods. Components of airway remodeling include epithelial cell shedding and dysfunction, goblet cell hyperplasia, subepithelial matrix protein deposition, fibrosis, neoangiogenesis, airway smooth muscle cell hypertrophy and hyperplasia. Among the other important, and frequently forgotten aspects of airway remodeling, also loss of epithelial barrier integrity, immune defects in anti-infectious defence and mucociliary clearance (MCC) dysfunction should be pointed out. Mucociliary clearance represents one of the most important defence airway mechanisms. Several studies in asthmatics demonstrated various dysfunctions in MCC - e.g., ciliated cells displaying intracellular disorientation, abnormal cilia and cytoplasmic blebs. Moreover, excessive mucus production and persistent cough are one of the well-recognized features of severe asthma and are also associated with defects in MCC. Damaged airway epithelium and impaired function of the ciliary cells leads to MCC dysfunction resulting in higher susceptibility to infection and inflammation. Therefore, new strategies aimed on restoring the remodeling changes and MCC dysfunction could present a new therapeutic approach for the management of asthma and other chronic respiratory diseases.

Mepolizumab treatment in a patient with previous liver transplantation: One year follow-up

Severe Asthma (SA) is characterized by inadequate disease control despite maximal inhalation therapy. In November 2021, a 68-years old female patient presented at our facility referring a worsening in her asthma-related symptoms and a high exacerbations rate. She reported a liver transplantation in 2015 and was in treatment with tacrolimus. We started treatment with Mepolizumab 100 mg once every 28 days and monitored her lung function as well as her lymphocytes subsets. After one year follow-up, the patient had a substantial improvement in lung function, exacerbation rate, daily OCS intake dose and no variation in the blood concentration of tacrolimus.

Eosinophils and tissue remodeling: Relevance to airway disease

The ability of human tissue to reorganize and restore its existing structure underlies tissue homeostasis in the healthy airways, but in disease can persist without normal resolution, leading to an altered airway structure. Eosinophils play a cardinal role in airway remodeling both in health and disease, driving epithelial homeostasis and extracellular matrix turnover. Physiological consequences associated with eosinophil-driven remodeling include impaired lung function and reduced bronchodilator reversibility in asthma, and obstructed airflow in chronic rhinosinusitis with nasal polyps. Given the contribution of airway remodeling to the development and persistence of symptoms in airways disease, targeting remodeling is an important therapeutic consideration. Indeed, there is early evidence that eosinophil attenuation may reduce remodeling and disease progression in asthma. This review provides an overview of tissue remodeling in both health and airway disease with a particular focus on eosinophilic asthma and chronic rhinosinusitis with nasal polyps, as well as the role of eosinophils in these processes and the implications for therapeutic interventions. Areas for future research are also noted, to help improve our understanding of the homeostatic and pathological roles of eosinophils in tissue remodeling, which should aid the development of targeted and effective treatments for eosinophilic diseases of the airways.

Advancing precision medicine in asthma: Evolution of treatment outcomes

The article discusses the historical evolution of asthma treatment and highlights recent advancements in personalized medicine, specifically the use of biologics in severe asthma therapy and its potential combination with allergen immunotherapy (AIT). One of the major breakthroughs of biologics is their potential effect on airway remodeling, a crucial aspect of asthma chronicity. The article introduces the concept of disease-modifying antiasthmatic drugs, which aim to modify the course of asthma and possibly modulate or prevent airway remodeling. Furthermore, the critical importance of patient-centered outcome measures to evaluate the efficacy and effectiveness of asthma treatments is emphasized, with the innovative concept of asthma remission introduced as a potential outcome. Recent studies suggest that AIT can be used as an additional therapy to biologic agents for the treatment of allergic asthma. The combination of these treatments has been shown to induce improved clinical outcomes. However, AIT is actually not recommended for use in patients with severe asthma, but encouraging results from studies investigating the combined use of AIT and biologics indicate a novel approach to exploring these treatment modalities. In conclusion, the introduction of biologics and AIT has changed the scenario of respiratory allergy treatment, from a "one size fits all" approach to embracing "individual treatments."

Pulmonary inflammation and fibroblast immunoregulation: from bench to bedside

In recent years, there has been an explosion of interest in how fibroblasts initiate, sustain, and resolve inflammation across disease states. Fibroblasts contain heterogeneous subsets with diverse functionality. The phenotypes of these populations vary depending on their spatial distribution within the tissue and the immunopathologic cues contributing to disease progression. In addition to their roles in structurally supporting organs and remodeling tissue, fibroblasts mediate critical interactions with diverse immune cells. These interactions have important implications for defining mechanisms of disease and identifying potential therapeutic targets. Fibroblasts in the respiratory tract, in particular, determine the severity and outcome of numerous acute and chronic lung diseases, including asthma, chronic obstructive pulmonary disease, acute respiratory distress syndrome, and idiopathic pulmonary fibrosis. Here, we review recent studies defining the spatiotemporal identity of the lung-derived fibroblasts and the mechanisms by which these subsets regulate immune responses to insult exposures and highlight past, current, and future therapeutic targets with relevance to fibroblast biology in the context of acute and chronic human respiratory diseases. This perspective highlights the importance of tissue context in defining fibroblast-immune crosstalk and paves the way for identifying therapeutic approaches to benefit patients with acute and chronic pulmonary disorders.

The Management of Chronic Rhinosinusitis With Nasal Polyps (CRSwNP) With Biologics

Chronic rhinosinusitis with nasal polyps affects a significant portion of the worldwide population. This illness is associated with several chronic conditions and has an important impact on patient quality of life, leading to a great societal economic burden. In recent years, biologic medications have been developed and found to be effective in the treatment of chronic rhinosinusitis with nasal polyps. This review focuses on these treatment options and their ability to improve patient outcomes, including quality of life. It also reviews available evidence with regards to patient selection, monitoring of patients after treatment initiation, and comparison of different biologics and with other treatment options such as sinus surgery.

Type 2 chronic inflammatory diseases: targets, therapies and unmet needs

Over the past two decades, significant progress in understanding of the pathogenesis of type 2 chronic inflammatory diseases has enabled the identification of compounds for more than 20 novel targets, which are approved or at various stages of development, finally facilitating a more targeted approach for the treatment of these disorders. Most of these newly identified pathogenic drivers of type 2 inflammation and their corresponding treatments are related to mast cells, eosinophils, T cells, B cells, epithelial cells and sensory nerves. Epithelial barrier defects and dysbiotic microbiomes represent exciting future drug targets for chronic type 2 inflammatory conditions. Here, we review common targets, current treatments and emerging therapies for the treatment of five major type 2 chronic inflammatory diseases - atopic dermatitis, chronic prurigo, chronic urticaria, asthma and chronic rhinosinusitis with nasal polyps - with a high need for targeted therapies. Unmet needs and future directions in the field are discussed.

Epithelial-Mesenchymal Transition Mechanisms in Chronic Airway Diseases: A Common Process to Target?

Epithelial-to-mesenchymal transition (EMT) is a reversible process, in which epithelial cells lose their epithelial traits and acquire a mesenchymal phenotype. This transformation has been described in different lung diseases, such as lung cancer, interstitial lung diseases, asthma, chronic obstructive pulmonary disease and other muco-obstructive lung diseases, such as cystic fibrosis and non-cystic fibrosis bronchiectasis. The exaggerated chronic inflammation typical of these pulmonary diseases can induce molecular reprogramming with subsequent self-sustaining aberrant and excessive profibrotic tissue repair. Over time this process leads to structural changes with progressive organ dysfunction and lung function impairment. Although having common signalling pathways, specific triggers and regulation mechanisms might be present in each disease. This review aims to describe the various mechanisms associated with fibrotic changes and airway remodelling involved in chronic airway diseases. Having better knowledge of the mechanisms underlying the EMT process may help us to identify specific targets and thus lead to the development of novel therapeutic strategies to prevent or limit the onset of irreversible structural changes.

LPS binding protein and activation signatures are upregulated during asthma exacerbations in children

Asthma exacerbations in children are associated with respiratory viral infection and atopy, resulting in systemic immune activation and infiltration of immune cells into the airways. The gene networks driving the immune activation and subsequent migration of immune cells into the airways remains incompletely understood. Cellular and molecular profiling of PBMC was employed on paired samples obtained from atopic asthmatic children (n = 19) during acute virus-associated exacerbations and later during convalescence. Systems level analyses were employed to identify coexpression networks and infer the drivers of these networks, and validation was subsequently obtained via independent samples from asthmatic children. During exacerbations, PBMC exhibited significant changes in immune cell abundance and upregulation of complex interlinked networks of coexpressed genes. These were associated with priming of innate immunity, inflammatory and remodelling functions. We identified activation signatures downstream of bacterial LPS, glucocorticoids and TGFB1. We also confirmed that LPS binding protein was upregulated at the protein-level in plasma. Multiple gene networks known to be involved positively or negatively in asthma pathogenesis, are upregulated in circulating PBMC during acute exacerbations, supporting the hypothesis that systemic pre-programming of potentially pathogenic as well as protective functions of circulating immune cells preceeds migration into the airways. Enhanced sensitivity to LPS is likely to modulate the severity of acute asthma exacerbations through exposure to environmental LPS.

New insights into the pathophysiology and therapeutic targets of asthma and comorbid chronic rhinosinusitis with or without nasal polyposis

Asthma and chronic rhinosinusitis with nasal polyps (CRSwNP) or without (CRSsNP) are chronic respiratory diseases. These two disorders often co-exist based on common anatomical, immunological, histopathological, and pathophysiological basis. Usually, asthma with comorbid CRSwNP is driven by type 2 (T2) inflammation which predisposes to more severe, often intractable, disease. In the past two decades, innovative technologies and detection techniques in combination with newly introduced targeted therapies helped shape our understanding of the immunological pathways underlying inflammatory airway diseases and to further identify several distinct clinical and inflammatory subsets to enhance the development of more effective personalized treatments. Presently, a number of targeted biologics has shown clinical efficacy in patients with refractory T2 airway inflammation, including anti-IgE (omalizumab), anti-IL-5 (mepolizumab, reslizumab)/anti-IL5R (benralizumab), anti-IL-4R-α (anti-IL-4/IL-13, dupilumab), and anti-TSLP (tezepelumab). In non-type-2 endotypes, no targeted biologics have consistently shown clinical efficacy so far. Presently, multiple therapeutical targets are being explored including cytokines, membrane molecules and intracellular signalling pathways to further expand current treatment options for severe asthma with and without comorbid CRSwNP. In this review, we discuss existing biologics, those under development and share some views on new horizons.

Pathogenic helper T cells as the novel therapeutic targets for immune-mediated intractable diseases

Allergic diseases arise from a complex interplay between immune system and environmental factors. A link between the pathogenesis of allergic diseases and type 2 immune responses has become evident, with conventional and pathogenic type 2 helper T (Th2) cells involved in both. Recently, there has been a significant development in therapeutic agents for allergic diseases: IL-5 and IL-5 receptor antagonists, Janus kinase (JAK) inhibitors, and sublingual immunotherapy (SLIT). Mepolizumab, an IL-5, and Benralizumab, an IL-5 receptor antagonist, modulate eosinophilic inflammation mediated by IL-5-producing Th2 cells. Delgocitinib shows that JAK-associated signaling is essential for the inflammatory reaction in atopic dermatitis, one of the common allergic diseases. SLIT has a significant effect on allergic rhinitis by reducing pathogenic Th2 cell numbers. More recently, novel molecules that are involved in pathogenic Th2 cell-mediated allergic diseases have been identified. These include calcitonin gene-related peptide (CGRP), reactive oxygen species (ROS) scavenging machinery regulated by the Txnip-Nrf2-Blvrb axis, and myosin light chain 9 (Myl9), which interacts with CD69. This review provides an updated view of the recent research on treatment of allergic diseases and their cause: conventional and pathogenic Th2 cells.

Involvement of Transforming Growth Factor-β-Associated Kinase 1 in Fixed Airway Obstruction in Asthmatic Patients with Longer Disease Duration Independent on Airway Eosinophilia

Objective

Transforming growth factor-β-associated kinase 1 (TAK1) mediates non-canonical TGF-β signalling by promoting adhesive, migratory, proliferative and contractile responses of fibroblasts to TGF-β₁. However, TAK1 expression status in asthmatic patients with or without fixed airway obstruction (FAO) is unknown.

Patients and Methods

A total of 60 adult asthmatics with FAO were recruited and compared to 43 those without FAO (nFAO). TGF-β₁ concentrations, and total TAK1 and phosphorylated TAK1 (p-TAK1) levels were determined in sputum supernatants, cytospin, and whole cell lysate by ELISA, immunocytochemistry, and Western blot analysis, respectively, in asthmatics with and without FAO.

Results

Asthmatic patients with FAO had much greater sputum TGF-β₁ concentrations than those without FAO. This was independent of airway eosinophilia as there was no significant difference in TGF-β₁ levels between high and low eosinophil counts within FAO and nFAO groups. In contrast, patients with FAO in the presence of sputum eosinophilia had greater expression of TAK1 and p-TAK1 than those without sputum eosinophilia (P=0.0032 and P=0.0061, respectively). The Western Blot data of total TAK1 and p-TAK1 were consistent with the immunocytochemistry, showing upregulation in all sputum cell types (neutrophils, eosinophils, macrophages, lymphocytes and airway epithelial cells). In addition, total TAK1 expression negatively correlated with pre- and post-bronchodilator FEV₁/FVC ratio.

Conclusion

TAK1 may play a key role in asthmatic patients with fixed airway obstruction, which was independent of eosinophilic airway inflammation. The interruption of TAK1 might have favourable clinical impact.

Biologic Therapies for Asthma and Allergic Disease: Past, Present, and Future

The discovery of the mechanism underlying allergic disease, mouse models of asthma, and bronchoscopy studies provided initial insights into the role of Th2-type cytokines, including interlukin (IL)-4, IL-5 and IL-13, which became the target of monoclonal antibody therapy. Omalizumab, Benralizumab, Mepolizumab, Reslizumab, and Tezepelumab have been approved. These biologicals have been shown to be good alternative therapies to corticosteroids, particularly in severe asthma management, where they can improve the quality of life of many patients. Given the success in asthma, these drugs have been used in other diseases with type 2 inflammation, including chronic rhinosinusitis with nasal polyps (CRSwNP), atopic dermatitis, and chronic urticaria. Like the Th2-type cytokines, chemokines have also been the target of novel monoclonal therapies. However, they have not proved successful to date. In this review, targeted therapy is addressed from its inception to future applications in allergic diseases.

Real-Life Effectiveness of Mepolizumab in Refractory Chronic Rhinosinusitis with Nasal Polyps

The aim of this study was to evaluate the efficacy of mepolizumab in patients affected by chronic rhinosinusitis with nasal polyps (CRSwNP) in real-life. A single-center retrospective observational study was conducted on severe CRSwNP patients treated with mepolizumab. Nasal endoscopic polyp score (NPS), visual analogue scale (VAS) symptom score, sinonasal outcome test (SNOT-22), asthma control test (ACT) score, fractional exhaled nitric oxide (FeNO), eosinophils blood cells and prednisone intake were assessed at baseline and after 6 months. A total of 55 patients were included; 49 patients (89%) presented with asthma; aspirin exacerbated respiratory disease (AERD) in 28 patients (51%). A statistically significant decrease in the SNOT-22 score was observed (median difference -63; 95% CI: -68; -58; p < 0.001) with median t0 76 and IQR (61;90) to t6 10 (5;15). A reduction in NPS, median t0 NPS 4; (IQR:4;6), median t6 NPS 1; (IQR:0;1) p < 0.001, was greater in patients with AERD. The median baseline VAS score was 6 (IQR:6;7) and the differences between t0 and t6 were statistically significant p < 0.001. Significant changes in blood eosinophils cells, median t0 500 cell/mcl (IQR:340;830), median t6 97 cell/mcl (IQR:60;160) p < 0.001, were greater in patients with AERD. Mepolizumab treatment effects have been demonstrated with significantly reduced symptoms, polyp scores, blood eosinophils and systemic corticosteroid use, resulting in an increased health-related quality of life in patients with severe CRSwNP, regardless of the presence or absence of asthma or AERD.

Translating the biology of β common receptor-engaging cytokines into clinical medicine

The family of cytokines that comprises IL-3, IL-5, and GM-CSF was discovered over 30 years ago, and their biological activities and resulting impact in clinical medicine has continued to expand ever since. Originally identified as bone marrow growth factors capable of acting on hemopoietic progenitor cells to induce their proliferation and differentiation into mature blood cells, these cytokines are also recognized as key mediators of inflammation and the pathobiology of diverse immunologic diseases. This increased understanding of the functional repertoire of IL-3, IL-5, and GM-CSF has led to an explosion of interest in modulating their functions for clinical management. Key to the successful clinical translation of this knowledge is the recognition that these cytokines act by engaging distinct dimeric receptors and that they share a common signaling subunit called β-common or βc. The structural determination of how IL-3, IL-5, and GM-CSF interact with their receptors and linking this to their differential biological functions on effector cells has unveiled new paradigms of cell signaling. This knowledge has paved the way for novel mAbs and other molecules as selective or pan inhibitors for use in different clinical settings.

Tenascin C in Lung Diseases

Tenascin C (TNC) is a multifunctional large extracellular matrix protein involved in numerous cellular processes in embryonic development and can be increased in disease, or under conditions of trauma or cell stress in adults. However, the role of TNC in lung diseases remains unclear. In this study, we investigated the expression of TNC during development, in offspring following maternal particulate matter (PM) exposure, asthma, chronic obstructive pulmonary disease (COPD) and lung cancer. TNC expression is increased during lung development in biopsy cells, endothelial cells, mesenchymal cells, and epithelial cells. Maternal PM exposure increased TNC and collagen deposition, which was not affected by the removal of PM exposure after pregnancy. TNC expression was also increased in basal epithelial cells and fibroblasts in patients with asthma and AT2 and endothelial cells in patients with COPD. Furthermore, there was an increase in the expression of TNC in stage II compared to stage IA lung cancer; however, overall survival analysis showed no correlation between levels of TNC and survival. In conclusion, TNC is increased during lung development, in offspring following maternal PM exposure, and in asthma, COPD, and lung cancer tissues. Therefore, targeting TNC may provide a novel therapeutic target for lung diseases.

The Pathology of Asthma: What Is Obstructing Our View?

Despite the advent of sophisticated and efficient new biologics to treat inflammation in asthma, the disease persists. Even following treatment, many patients still experience the well-known symptoms of wheezing, shortness of breath, and coughing. What are we missing? Here we examine the evidence that mucus plugs contribute to a substantial portion of disease, not only by physically obstructing the airways but also by perpetuating inflammation. In this way, mucus plugs may act as an immunogenic stimulus even in the absence of allergen or with the use of current therapeutics. The alterations of several parameters of mucus biology, driven by type 2 inflammation, result in sticky and tenacious sputum, which represents a potent threat, first due to the difficulties in expectoration and second by acting as a platform for viral, bacterial, or fungal colonization that allows exacerbations. Therefore, in this way, mucus plugs are an overlooked but critical feature of asthmatic airway disease.

Airway remodeling heterogeneity in asthma and its relationship to disease outcomes

Asthma affects an estimated 262 million people worldwide and caused over 461,000 deaths in 2019. The disease is characterized by chronic airway inflammation, reversible bronchoconstriction, and airway remodeling. Longitudinal studies have shown that current treatments for asthma (inhaled bronchodilators and corticosteroids) can reduce the frequency of exacerbations, but do not modify disease outcomes over time. Further, longitudinal studies in children to adulthood have shown that these treatments do not improve asthma severity or fixed airflow obstruction over time. In asthma, fixed airflow obstruction is caused by remodeling of the airway wall, but such airway remodeling also significantly contributes to airway closure during bronchoconstriction in acute asthmatic episodes. The goal of the current review is to understand what is known about the heterogeneity of airway remodeling in asthma and how this contributes to the disease process. We provide an overview of the existing knowledge on airway remodeling features observed in asthma, including loss of epithelial integrity, mucous cell metaplasia, extracellular matrix remodeling in both the airways and vessels, angiogenesis, and increased smooth muscle mass. While such studies have provided extensive knowledge on different aspects of airway remodeling, they have relied on biopsy sampling or pathological assessment of lungs from fatal asthma patients, which have limitations for understanding airway heterogeneity and the entire asthma syndrome. To further understand the heterogeneity of airway remodeling in asthma, we highlight the potential of in vivo imaging tools such as computed tomography and magnetic resonance imaging. Such volumetric imaging tools provide the opportunity to assess the heterogeneity of airway remodeling within the whole lung and have led to the novel identification of heterogenous gas trapping and mucus plugging as important predictors of patient outcomes. Lastly, we summarize the current knowledge of modification of airway remodeling with available asthma therapeutics to highlight the need for future studies that use in vivo imaging tools to assess airway remodeling outcomes.

Impact of Anti-IL5 Therapies on Patients with Severe Uncontrolled Asthma and Possible Predictive Biomarkers of Response: A Real-Life Study

Severe Uncontrolled Asthma (SUA) counts for more than 25% of cases of severe asthma. The main factors that impair the quality of life of these patients are high doses of oral corticosteroids, the presence of exacerbations, and reduced lung function. The objective of this study was to evaluate, in real life, the clinical improvement of patients with SUA treated with anti-interleukin 5 (IL5) therapies: mepolizumab and benralizumab, together with the search for biomarkers associated with the response. We conducted a retrospective observational cohort study that included patients with severe uncontrolled eosinophilic asthma in a tertiary hospital receiving biological therapies. Three types of response were evaluated: improvement in lung function, reduction in exacerbations, and decrease in the use of oral corticosteroids. After 12 months of treatment, significant reductions were found in the number of exacerbations, the use of oral corticosteroids, and blood eosinophil levels for both biological therapies (p < 0.001). Lung function improved, achieving a significant improvement in %FEV1 (p < 0.001), as well as asthma control, with a significant increase in asthma control test (ACT) scores in both therapies. The markers associated with the corticosteroid-saving effect were the low doses of oral corticosteroids and absence of exacerbations for mepolizumab, and higher blood eosinophilia, absence of chronic obstructive pulmonary disease (COPD), and reduction in oral corticosteroid cycles for benralizumab. The greatest improvement in lung function in both therapies was linked to lower previous FEV1 levels and absence of other respiratory diseases. The reduction in exacerbations was associated with absence of exacerbations the previous year for mepolizumab and never smokers for benralizumab. The results of this real-life study confirm the clinical benefit obtained after the introduction of an anti-IL5 biological therapy and the possible predictive biomarkers of response to treatment.

Trends of therapy in the treatment of asthma

BACKGROUND

To better understand the development of therapy for asthma, grasp the core paradigm associated with the transformation of cognition of asthma treatment and asthma, explore potential and effective therapies for asthma, discover new biomarkers and mechanisms related to asthma treatment, find novel targets for anti-asthma drugs, and predict the future trends of asthma therapy, we used a bibliometric analysis to research articles related to the therapies for asthma published from 1983 to 2022.

METHODS

A comprehensive search was conducted to analyze the articles associated with therapy for asthma with the help of the Web of Science Core Collection (WOSCC) database from January 1, 1983 to August 14, 2022. The CiteSpace 6.1.R2 software and VOS viewer 6.1.8 software were utilized to analyze the overall structure of the network, network clusters, links between clusters, key nodes, and pathways.

RESULTS

A total of 3902 publications related to therapies on asthma were published in 3211 academic journals by a total of 14,655 authors in 3476 organizations from 87 countries or regions from 1983 to 2022. The United States published the most articles (n = 1143), followed by England (n = 574) and China (n = 405). However, the centrality of China was 0.4, higher than the United States (centrality = 0.16) and Singapore (centrality = 0.11). Akdis Cezmi published the most papers. Journal of Allergy and Clinical Immunology published the most studies on therapies for asthma. Asthma was the most frequent keyword (n = 594). The betweenness centrality value of keywords that were greater than 0.1 included airway inflammation (centrality = 0.22), double blind (centrality = 0.18), asthma (centrality = 0.17), inflammation (centrality = 0.12), and inhaled corticosteroid (centrality = 0.11).

CONCLUSIONS

The results from this biometric review provide insight into the development of therapy for asthma, the paradigm of recognition of this field, the approach of discovering new targets, exploration and combination of new mechanisms, and the frontier trend of this field in future.