Specific elastin degradation products are associated with poor outcome in the ECLIPSE COPD cohort

Abstract Chronic obstructive pulmonary disease (COPD) is characterized by a slow heterogeneous progression. Therefore, improved biomarkers that can accurately identify patients with the highest likelihood of progression and therefore the ability to benefit from a given treatment, are needed. Elastin is an essential structural protein of the lungs. In this study, we investigated whether elastin degradation products generated by the enzymes proteinase 3, cathepsin G, neutrophil elastase, MMP7 or MMP9/12 were prognostic biomarkers for COPD-related outcomes. The elastin degradome was assessed in a subpopulation (n = 1307) of the Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE) cohort with 3 years of clinical follow-up. Elastin degraded by proteinase 3 could distinguish between COPD participants and non-smoking controls (p = 0.0006). A total of 30 participants (3%) died over the 3 years of observation. After adjusting for confounders, plasma levels of elastin degraded by proteinase 3 and cathepsin G were independently associated with mortality outcome with a hazard ratio per 1 SD of 1.49 (95%CI 1.24–1.80, p < 0.0001) and 1.31 (95%CI 1.10–1.57, p = 0.0029), respectively. Assessing the elastin degradome demonstrated that specific elastin degradation fragments have potential utility as biomarkers identifying subtypes of COPD patients at risk of poor prognosis and supports further exploration in confirmatory studies

A serological biomarker of type I collagen degradation is related to a more severe, high neutrophilic, obese asthma subtype

BACKGROUND: Asthma is a heterogeneous disease; therefore, biomarkers that can assist in the identification of subtypes and direct therapy are highly desirable. Asthma is a chronic inflammatory disease that leads to changes in the extracellular matrix (ECM) by matrix metalloproteinases (MMPs) degradation causing fragments of type I collagen that is released into circulation. OBJECTIVE: Here, we asked if MMP-generated type I collagen (C1M) was associated with subtypes of asthma. METHODS: C1M was serologically assessed at baseline in the adult participants of the All Age Asthma study (ALLIANCE) (n = 233), and in The Prospective Epidemiological Risk Factor study (PERF) (n = 283). In addition, C1M was assessed in mice sensitized to ovalbumin (OVA) and challenged with OVA aerosol. C1M was evaluated in mice with and without acute neutrophilic inflammation provoked by poly(cytidylic-inosinic) acid and mice treated with CP17, a peptide inhibiting neutrophil accumulation. RESULTS: Serum C1M was significantly increased in asthmatics compared to healthy controls (p = 0.0005). We found the increased C1M levels in asthmatics were related to blood neutrophil and body mass index (BMI) in the ALLIANCE cohort, which was validated in the PERF cohort. When patients were stratified into obese (BMI > 30) asthmatics with high neutrophil levels and uncontrolled asthma, this group had a significant increase in C1M compared to normal-weight (BMI < 25) asthmatics with low neutrophil levels and controlled asthma (p = 0.0277). C1M was significantly elevated in OVA mice with acute neutrophilic inflammation compared to controls (P = 0.0002) and decreased in mice treated with an inhibitor of neutrophil infiltration (p = 0.047). CONCLUSION & CLINICAL RELEVANCE: C1M holds the potential to identify a subtype of asthma that relates to severity, obesity, and high neutrophils. These data suggest that C1M is linked to a subtype of overall inflammation, not only derived from the lung. The link between C1M and neutrophils were further validated in in vivo model. TRIAL REGISTRATION: (ALLIANCE, NCT02419274). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40733-022-00084-6

COL4A3 is degraded in allergic asthma and degradation predicts response to anti-IgE therapy.

BACKGROUND Asthma is a heterogeneous syndrome substantiating the urgent requirement for endotype-specific biomarkers. Dysbalance of fibrosis and fibrolysis in asthmatic lung tissue leads to reduced levels of the inflammation-protective collagen 4 (COL4A3). OBJECTIVE To delineate the degradation of COL4A3 in allergic airway inflammation and evaluate the resultant product as a biomarker for anti-IgE therapy response. METHODS The serological COL4A3 degradation marker C4Ma3 (Nordic Bioscience, Denmark) and serum cytokines were measured in the ALLIANCE cohort (pediatric cases/controls: 134/35; adult cases/controls: 149/31). Exacerbation of allergic airway disease in mice was induced by sensitising to OVA, challenge with OVA aerosol and instillation of poly(cytidylic-inosinic). Fulacimstat (chymase inhibitor, Bayer) was used to determine the role of mast cell chymase in COL4A3 degradation. Patients with cystic fibrosis (CF, n=14) and CF with allergic broncho-pulmonary aspergillosis (ABPA, n=9) as well as severe allergic, uncontrolled asthmatics (n=19) were tested for COL4A3 degradation. Omalizumab (anti-IgE) treatment was assessed by the Asthma Control Test. RESULTS Serum levels of C4Ma3 were increased in asthma in adults and children alike and linked to a more severe, exacerbating allergic asthma phenotype. In an experimental asthma mouse model, C4Ma3 was dependent on mast cell chymase. Serum C4Ma3 was significantly elevated in CF plus ABPA and at baseline predicted the success of the anti-IgE therapy in allergic, uncontrolled asthmatics (diagnostic odds ratio 31.5). CONCLUSION C4Ma3 level depend on lung mast cell chymase and are increased in a severe, exacerbating allergic asthma phenotype. C4Ma3 may serve as a novel biomarker to predict anti-IgE therapy response

Development of a Novel Enzyme-Linked Immunosorbent Assay Targeting a Neo-Epitope Generated by Cathepsin-Mediated Turnover of Type III Collagen and Its Application in Chronic Obstructive Pulmonary Disease.

A high level of extracellular matrix (ECM) turnover characterizes several lung diseases with fibrotic features. Type III collagen is one of the most abundant collagens in lung parenchyma, and cathepsins play a role in lung pathology, being responsible for tissue remodeling. In this study, we explore the diagnostic features of neo-epitope fragments of type III collagen generated by cathepsins that could reflect the pathological tissue turnover in patients with different diseases. A novel enzyme-linked immunosorbent assay (ELISA) measuring cathepsins B, L, S and K -generated type III collagen fragments (C3C) was developed for assessment in serum and plasma. The assay was biologically validated in serum from patients with chronic obstructive pulmonary disease (COPD). Serological levels of C3C were significantly elevated in patients with COPD compared to healthy controls (p = 0.0006). Levels of C3C in serum and heparin plasma of COPD patients had a highly significant correlation (R2 = 0.86, p<0.0001). The data suggests that the C3C fragment is elevated in patients with COPD compared to healthy controls

Analyte stability in human serum.

<p>The serum samples were either subjected to four freeze/thaw cycles or stored at 4 or 20°C for 0, 2, 4 and 24 hours. All data are shown as mean percent recovery (RE%) compared to baseline (ie, 1 freeze/thaw cycle and storage time 0 hours, respectively).</p

Inter- and intra-assay variation for the C3C assay.

<p>As quality controls (QC1-5), human sera was used. The controls (CO1 and -2) included in every run of the C3C ELISA were also included. The variation was calculated as the mean variation between 10 individual runs of each sample run in double determination.</p

Patient demographics.

<p>Patient demographics.</p

Percentage dilution recovery for the C3C assay using human serum and plasma samples.

<p>Samples were measured from undiluted to 1:4 diluted and linearity was assessed.</p

Spiking recovery of standard peptide in human serum, and high serum in low serum.

<p>The recovery (RE%) was calculated as the percentage recovery of the measured amount in the sample alone. The experiment was performed for three separate healthy human control sera. The standard peptide was added in 2-fold dilutions starting from 50 ng/mL (StdB) and high serum was added in 2-fold dilution starting from 1:2.</p

Products used for cleavage analysis.

<p>Products used for cleavage analysis.</p