Biomarkers in asthma: a real hope to better manage asthma

Effects of Family-Supported Healthcare on Children with Asthma

Introduction

Healthcare is essential for asthma control, however, whether family-supported healthcare improves therapeutic effects in childhood asthma remains unclear.

Methods

The enrolled patients were randomly divided into control and intervention groups. The pulmonary function was evaluated by forced expiratory volume in 1 s as a percentage of forced vital capacity (FEV1/FVC) and fractional exhaled nitric oxide (FeNO). Asthma control and life quality were assessed via a childhood asthma control test and pediatric asthma quality of life questionnaire. Inflammatory cytokines interleukin-6 (IL-6) and interleukin-17 (IL-17) were determined by enzyme-linked immunosorbent assay.

Results

No significant differences existed in the basic characteristics of asthma children and their parents among two groups. The increase of FEV1/FVC was higher in the intervention group versus the control group (76.47 ± 10.76% vs 69.76 ± 8.88%, p = 0.001 at the time of post-intervention), and the decrease of FeNO was greater in the intervention group (30.43 ± 6.85 bbp vs 35.64 ± 6.62 bbp, p = 0.003 at the time of post-intervention). Family-supported healthcare highly improved asthma control and quality of life in childhood asthma post-treatment. Meanwhile, the inflammatory cytokines IL-17 (118.14 ± 25.79 pg/mL in intervention group vs 142.86 ± 28.68 pg/mL in control group, p = 0.004 at the time of post-intervention) and IL-6 (103.76 ± 23.11 pg/mL in intervention group vs 119.73 ± 22.68 pg/mL in control group, p = 0.009 at the time of post-intervention) significantly decreased by family-supported healthcare intervention. Importantly, acute exacerbation (80.8% in intervention group vs 95.7% in control group, p = 0.030) and rehospitalization cases (88.5% in intervention group vs 100% in control group, p = 0.028) also decreased by family-supported healthcare intervention.

Discussion

Family-supported healthcare improves pulmonary function and quality of life while alleviates inflammation, acute exacerbation, and rehospitalization in childhood asthma post-routine treatment.

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Diagnostic value of IL-6 for patients with asthma: a meta-analysis

BACKGROUND

IL-6 is a pleotropic cytokine that acts as a pro-inflammatory mediator and acute-phase response inducer, but has also been reported to possess anti-inflammatory properties. The objective of this study was to assess the validity of serum IL-6 test for diagnosis of asthma.

METHODS

A literature search was conducted using PubMed, Embase, and Cochrane library from January 2007 to March 2021 to identify relevant studies. Eleven studies were included in this analysis, involving 1977 patients with asthma and 1591 healthy non-asthmatic controls. The meta-analysis was performed using Review Manager 5.3 software and Stata 16.0. Random effect model or fixed effect model (FEM) was used to estimate the standardized mean differences (SMDs) with 95% confidence intervals (CIs).

RESULTS

The meta-analysis results revealed that the serum IL-6 levels were higher in asthmatic patients than healthy non-asthmatic controls (SMD 1.31, 95% CI 0.82-1.81, P < 0.00001). IL-6 levels are significantly elevated in pediatric patients with asthma (SMD 1.58, 95% CI 0.75-2.41, P = 0.0002) and mildly elevated in adult patients with asthma (SMD 1.08, 95% CI 0.27-1.90, P = 0.009). In addition, a subgroup analysis of asthma disease status showed that IL-6 levels were increased in stable (SMD 0.69, 95% CI 0.28-1.09, P = 0.009) and exacerbation asthma (SMD 2.15, 95% CI 1.79-2.52, P < 0.00001) patients.

CONCLUSION

The results of this meta-analysis suggest that serum IL-6 levels were significantly elevated in asthmatic patients as compared to normal population. IL-6 levels can be used as an auxiliary indicator to distinguish individuals with asthma from healthy non-asthmatic controls.

The emerging roles of eosinophils: Implications for the targeted treatment of eosinophilic-associated inflammatory conditions

Eosinophils have multiple relevant biological functions, including the maintenance of homeostasis, host defense against infectious agents, innate immunity activities, immune regulation through Th1/Th2 balance, anti-inflammatory, and anti-tumorigenic effects. Eosinophils also have a main role in tissue damage through eosinophil-derived cytotoxic mediators that are involved in eosinophilic inflammation, as documented in Th2-high asthma and other eosinophilic-associated inflammatory conditions.

Recent evidence shows that these multiple and apparently conflicting functions may be attributed to the existence of different eosinophil subtypes (i.e.: tissue resident and inducible eosinophils). Therapeutic intervention with biological agents that totally deplete tissues and circulating eosinophils or, vice versa, maintain a minimal proportion of eosinophils, particularly the tissue-resident ones, could therefore have a very different impact on patients, especially when considering the administration of these therapies for prolonged time. In addition, the characterization of the predominant pathway underlying eosinophilic inflammation by surrogate biomarkers (circulating eosinophils, organ-specific eosinophils levels such as eosinophil count in sputum, bronchoalveolar lavage, tissue biopsy; total circulating IgE levels, or the use of FeNO) in the single patient with an eosinophilic-associated inflammatory condition could help in choosing the treatment.

These observations are crucial in light of the increasing therapeutic armamentarium effective in modulating eosinophilic inflammation through the inhibition in different, yet complementary ways of eosinophil pathways, such as the interleukin-5 one (with mepolizumab, benralizumab, reslizumab) or the interleukin-4/13 one (with dupilumab and lebrikizumab), in severe T2-high asthma as well as in other systemic eosinophilic associated diseases, such as eosinophilic granulomatosis with polyangiitis and hypereosinophilic syndrome.

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Recent evidence pointed out the existence of different eosinophil subtypes, i.e. tissue resident and inducible eosinophils, with different and apparently conflicting functions.

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Biological therapies with different mechanisms can deplete completely tissues and circulating eosinophils or maintain a minimal proportion of eosinophils, particularly the tissue-resident ones, and this could therefore have a different impact on patients, especially when considering the administration of these therapies for prolonged time.

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The identification of the predominant pathway underlying eosinophilic inflammation by surrogate biomarkers (circulating eosinophils, organ-specific eosinophils levels such as eosinophil count in sputum, bronchoalveolar lavage, tissue biopsy; total circulating IgE levels, or the use of FeNO) should be sought in the single patient with an eosinophilic-associated inflammatory condition.

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These considerations may help in choosing the best anti-eosinophilic treatment, considering the increasing therapeutic armamentarium effective in modulating eosinophilic inflammation through the inhibition of the interleukin-5 one (with mepolizumab, benralizumab, reslizumab) or the interleukin-4/13 one (with dupilumab and lebrikizumab)

Urinary and exhaled biomarkers of exercise-induced bronchoconstriction in atopic asthmatic children

BACKGROUND

Exercise-induced bronchoconstriction (EIB) reflects poor asthma control. Assessing noninvasive biomarkers associated with EIB could help to monitor patients in the pediatric age.

AIMS

To test exhaled and urinary biomarkers for assessing EIB in atopic asthmatic children.

METHODS

In 45 atopic patients (11.1 ± 1.8 years, 25 males) we measured the fractional exhaled nitric oxide (FE_NO ), its alveolar (CaNO), and bronchial (J'awNO) components corrected for the trumpet shape of the airways and axial NO diffusion (TMAD), concentrations of urinary adenosine and 8-hydroxy-2'-deoxyguanosine (8-OxodG), blood eosinophils count, total immunoglobulin E , skin prick tests, and baseline spirometry before a treadmill exercise challenge. Forty healthy control subjects participated solely to baseline measurements.

RESULTS

Patients yielded higher FE_NO and urinary adenosine concentrations than healthy controls. After the challenge, 18 patients (40%) had EIB; these patients had higher levels of CaNO, CaNO TMAD, and urinary adenosine than patients without EIB. Baseline spirometry, FE _NO , JawNO, JawNO TMAD, urinary 8-OxodG, allergy, and blood eosinophil counts were found similar in both groups. In multiple linear regression, the fall in FEV ₁ was explained by CaNO TMAD, urinary adenosine and blood eosinophil count, whereas the fall in FEF _25-75 was explained by CaNO TMAD and blood eosinophil count. Both CaNO TMAD ≥10.5 ppb and urinary adenosine ≥406 nmol/mmol Cr predicted a fall in FEV ₁ ≥10%, while only CaNO TMAD ≥10.5 ppb predicted a fall in FEF _25-75 ≥26%.

CONCLUSION

Concentrations of peripheral airway NO are complementary with urinary adenosine for assessing EIB and promising tools of asthma control in pediatric patients with the atopic phenotype.

The Correlation between Chitin and Acidic Mammalian Chitinase in Animal Models of Allergic Asthma

Asthma is the result of chronic inflammation of the airways which subsequently results in airway hyper-responsiveness and airflow obstruction. It has been shown that an elicited expression of acidic mammalian chitinase (AMCase) may be involved in the pathogenesis of asthma. Our recent study has demonstrated that the specific suppression of elevated AMCase leads to reduced eosinophilia and Th2-mediated immune responses in an ovalbumin (OVA)-sensitized mouse model of allergic asthma. In the current study, we show that the elicited expression of AMCase in the lung tissues of both ovalbumin- and Der P2-induced allergic asthma mouse models. The effects of allergic mediated molecules on AMCase expression were evaluated by utilizing promoter assay in the lung cells. In fact, the exposure of chitin, a polymerized sugar and the fundamental component of the major allergen mite and several of the inflammatory mediators, showed significant enhancement on AMCase expression. Such obtained results contribute to the basis of developing a promising therapeutic strategy for asthma by silencing AMCase expression.

Childhood asthma biomarkers: present knowledge and future steps

Asthma represents the most common chronic respiratory disease of childhood. Its current standard diagnosis relies on patient history of symptoms and confirmed expiratory airflow limitation. Nevertheless, the spectrum of asthma in clinical presentation is broad, and both symptoms and lung function may not always reflect the underlying airway inflammation, which can be determined by different pathogenetic mechanisms. For these reasons, the identification of objective biomarkers of asthma, which may guide diagnosis, phenotyping, management and treatment is of great clinical utility and might have a role in the development of personalized therapy. The availability of non-invasive methods to study and monitor disease inflammation is of relevance especially in childhood asthma. In this sense, a promising role might be played by the measurement of exhaled biomarkers, such as exhaled nitric oxide (FE(NO)) and molecules in exhaled breath condensate (EBC). Furthermore, recent studies have shown encouraging results with the application of the novel metabolomic approach to the study of exhaled biomarkers. In this paper the existing knowledge in the field of asthma biomarkers, with a special focus on exhaled biomarkers, will be highlighted.

Metabolomic Endotype of Asthma

Metabolomics, the quantification of small biochemicals in plasma and tissues, can provide insight into complex biochemical processes and enable the identification of biomarkers that may serve as therapeutic targets. We hypothesized that the plasma metabolome of asthma would reveal metabolic consequences of the specific immune and inflammatory responses unique to endotypes of asthma. The plasma metabolomic profiles of 20 asthmatic subjects and 10 healthy controls were examined using an untargeted global and focused metabolomic analysis. Individuals were classified based on clinical definitions of asthma severity or by levels of fraction of exhaled NO (FENO), a biomarker of airway inflammation. Of the 293 biochemicals identified in the plasma, 25 were significantly different among asthma and healthy controls (p < 0.05). Plasma levels of taurine, lathosterol, bile acids (taurocholate and glycodeoxycholate), nicotinamide, and adenosine-5-phosphate were significantly higher in asthmatics compared with healthy controls. Severe asthmatics had biochemical changes related to steroid and amino acid/protein metabolism. Asthmatics with high FENO, compared with those with low FENO, had higher levels of plasma branched-chain amino acids and bile acids. Asthmatics have a unique plasma metabolome that distinguishes them from healthy controls and points to activation of inflammatory and immune pathways. The severe asthmatic and high FENO asthmatic have unique endotypes that suggest changes in NO-associated taurine transport and bile acid metabolism.

Urates in exhaled breath condensate as a biomarker of control in childhood asthma

OBJECTIVE

The aim of this study was to (1) investigate the possibility to use urates in exhaled breath condensate (EBC) as a biomarker of airway inflammation and control in childhood asthma and (2) explore their association with other biomarkers of airway inflammation and clinical indices of asthma control (Asthma Control Test [ACT], quality of life [PAQLQ], lung function, prn beta-agonist use, time from last exacerbation [TLE].

METHODS

This cross-sectional study comprised 103 consecutive patients (age 6-18 years) divided in groups of uncontrolled ([NC], n = 53) and controlled asthma ([C], n = 50). Measured lung function and biomarkers included: spirometry, eosinophilic cationic protein (ECP), high-sensitivity C-reactive protein (hs-CRP), exhaled NO (FENO), pH and urates in EBC and exhaled breath temperature (EBT).

RESULTS

Statistically significant differences were found between groups for EBC urates, EBC pH and EBT (NC versus C: EBC urates, median [IQR], µmol/L; 10 [6] versus 45 [29], p < 0.001; EBC pH, mean [SD], 7.2 [0.17] versus 7.33 [0.16], p = 0.002; EBT mean [SD], °C; 34.26 [0.83], versus 33.90 [0.60], p = 0.014). EBC urates showed significant association with TLE and FENO (r = 0.518, p < 0.001; r = 0.369, p = 0.007, respectively) in NC, and EBC pH (r = 0.351, p < 0.001), FEV1 (r = 0.222, p = 0.024), ACT (r = 0.654, p < 0.001), PAQLQ (r = 0.686, p < 0.001) and prn salbutamol use (r = -0.527, p < 0.001) in all asthmatics.

CONCLUSION

In our study, EBC urates were found to be the best single predictor of asthma control and underlying airway inflammation. Our results provide evidence supporting the potential utility to use EBC urates as an additional non-invasive biomarker of control in childhood asthma.

The metabolomics of airway diseases, including COPD, asthma and cystic fibrosis

Chronic obstructive pulmonary disease (COPD), asthma and cystic fibrosis (CF) are characterized by airway obstruction and an inflammatory process. Reaching early diagnosis and discrimination of subtypes of these respiratory diseases are quite a challenging task than other chronic illnesses. Metabolomics is the study of metabolic pathways and the measurement of unique biochemical molecules generated in a living system. In the last decade, metabolomics has already proved to be useful for the characterization of several pathological conditions and offers promises as a clinical tool. In this article, we review the current state of the metabolomics of COPD, asthma and CF with a focus on the different methods and instrumentation being used for the discovery of biomarkers in research and translation into clinic as diagnostic aids for the choice of patient-specific therapies.

Protein and microRNA biomarkers from lavage, urine, and serum in military personnel evaluated for dyspnea

Background

We have identified candidate protein and microRNA (miRNA) biomarkers for dyspnea by studying serum, lavage fluid, and urine from military personnel who reported serious respiratory symptoms after they were deployed to Iraq or Afghanistan.

Methods

Forty-seven soldiers with the complaint of dyspnea who enrolled in the STudy of Active Duty Military Personnel for Environmental Dust Exposure (STAMPEDE) underwent comprehensive pulmonary evaluations at the San Antonio Military Medical Center. The evaluation included fiber-optic bronchoscopy with bronchoalveolar lavage. The clinical findings from the STAMPEDE subjects pointed to seven general underlying diagnoses or findings including airway hyperreactivity, asthma, low diffusivity of carbon monoxide, and abnormal cell counts. The largest category was undiagnosed. As an exploratory study, not a classification study, we profiled proteins or miRNAs in lavage fluid, serum, or urine in this group to look for any underlying molecular patterns that might lead to biomarkers. Proteins in lavage fluid and urine were identified by accurate mass tag (database-driven) proteomics methods while miRNAs were profiled by a hybridization assay applied to serum, urine, and lavage fluid.

Results

Over seventy differentially expressed proteins were reliably identified both from lavage and from urine in forty-eight dyspnea subjects compared to fifteen controls with no known lung disorder. Six of these proteins were detected both in urine and lavage. One group of subjects was distinguished from controls by expressing a characteristic group of proteins. A related group of dyspnea subjects expressed a unique group of miRNAs that included one miRNA that was differentially overexpressed in all three fluids studied. The levels of several miRNAs also showed modest but direct associations with several standard clinical measures of lung health such as forced vital capacity or gas exchange efficiency.

Conclusions

Candidate proteins and miRNAs associated with the general diagnosis of dyspnea have been identified in subjects with differing medical diagnoses. Since these markers can be measured in readily obtained clinical samples, further studies are possible that test the value of these findings in more formal classification or case–control studies in much larger cohorts of subjects with specific lung diseases such as asthma, emphysema, or some other well-defined lung disease.

[Personalised medicine for the diagnosis and treatment of allergic diseases]

Immunoglobulin E (IgE) mediated allergic diseases are characterised by heterogeneous clinical phenotypes and a large variety of different sensitisation patterns. Apart from genetic predisposition several environmental factors play a role in sensitisation and elicitation of symptoms. Since the majority of clinically relevant allergens are now available as purified recombinant allergens component-resolved in vitro diagnosis allows the sensitization profile of allergic patients to be determined at the molecular level. Such data may allow physicians to draw conclusions on the severity and persistence of a given allergic disease and to predict the outcome of allergen-specific immunotherapy (SIT) However, the potential of this approach needs to be demonstrated in controlled clinical trials. Moreover, in the context of atopic dermatitis, allergic rhinitis, allergic bronchial asthma as well as the atopic march several screening-biomarkers, diagnostic and prognostic biomarkers, biomarkers of severity and predictive biomarkers are presented and discussed in this article. Traditionally a relevant proportion of allergen-specific immunotherapies is performed in a personalised manner using named patient products manufactured on the basis of an individual prescription. Such named patient products are often mixtures containing several allergen extracts from different sources. However, there is no proven evidence for the safety and efficacy of this approach. In Germany the Therapy Allergen Ordinance ("Therapieallergene-Verordnung", TAV) regulates that in the future allergen products for SIT of insect venom allergies, allergies to pollen of early flowering trees and grass pollen and house dust mite allergies cannot be marketed as named patient products, but always require a marketing authorisation. Thus personalised SIT with named patient products is restricted to the treatment of less prevalent allergies, for which the generation of state-of-the-art clinical data is more difficult. Several recombinant allergens are currently evaluated in phase III clinical trials. In contrast to allergen extracts recombinant allergens offer the possibility to treat patients with a precisely adjusted mixture of the disease-eliciting allergen molecules. However, the implementation of this personalised approach to SIT within the given regulatory framework represents a challenge to regulators.