Plasma Kallikrein-Activated TGF-ß Is Prognostic for Poor Overall Survival in Patients with Pancreatic Ductal Adenocarcinoma and Associates with Increased Fibrogenesis.

Pancreatic ductal adenocarcinoma (PDAC) is a hard-to-treat cancer due to the collagen-rich (fibrotic) and immune-suppressed microenvironment. A major driver of this phenomenon is transforming growth factor beta (TGF-ß). TGF-ß is produced in an inactive complex with a latency-associated protein (LAP) that can be cleaved by plasma kallikrein (PLK), hereby releasing active TGF-ß. The aim of this study was to evaluate LAP cleaved by PLK as a non-invasive biomarker for PDAC and tumor fibrosis. An ELISA was developed for the quantification of PLK-cleaved LAP-TGF-ß in the serum of 34 patients with PDAC (stage 1−4) and 20 healthy individuals. Biomarker levels were correlated with overall survival (OS) and compared to serum type III collagen (PRO-C3) and type VI collagen (PRO-C6) pro-peptides. PLK-cleaved LAP-TGF-ß was higher in patients with PDAC compared to healthy individuals (p < 0.0001). High levels (>median) of PLK-cleaved LAP-TGF-ß were associated with poor OS in patients with PDAC independent of age and stage (HR 2.57, 95% CI: 1.22−5.44, p = 0.0135). High levels of PLK-cleaved LAP-TGF-ß were associated with high PRO-C3 and PRO-C6, indicating a relationship between the PLK-cleaved LAP-TGF-ß fragment, TGF-ß activity, and tumor fibrosis. If these preliminary results are validated, circulating PLK-cleaved LAP-TGF-ß may be a biomarker for future clinical trials.

Type XX Collagen Is Elevated in Circulation of Patients with Solid Tumors.

In the tumor microenvironment, the extracellular matrix (ECM) has been recognized as an important part of cancer development. The dominant ECM proteins are the 28 types of collagens, each with a unique function in tissue architecture. Type XX collagen, however, is poorly characterized, and little is known about its involvement in cancer. We developed an ELISA quantifying type XX collagen, named PRO-C20, using a monoclonal antibody raised against the C-terminus. PRO-C20 and PRO-C1, an ELISA targeting the N-terminal pro-peptide of type I collagen, was measured in sera of 219 patients with various solid cancer types and compared to sera levels of 33 healthy controls. PRO-C20 was subsequently measured in a separate cohort comprising 36 patients with pancreatic ductal adenocarcinoma (PDAC) and compared to 20 healthy controls and 11 patients with chronic pancreatitis. PRO-C20 was significantly elevated in all cancers tested: bladder, breast, colorectal, head and neck, kidney, lung, melanoma, ovarian, pancreatic, prostate, and stomach cancer (p < 0.01−p < 0.0001). PRO-C1 was only elevated in patients with ovarian cancer. PRO-C20 could discriminate between patients and healthy controls with AUROC values ranging from 0.76 to 0.92. Elevated levels were confirmed in a separate cohort of patients with PDAC (p < 0.0001). High PRO-C20 levels (above 2.57 nM) were predictive of poor survival after adjusting for the presence of metastasis, age, and sex (HR: 4.25, 95% CI: 1.52−11.9, p-value: 0.006). Circulating type XX collagen is elevated in sera of patients with various types of cancer and has prognostic value in PDAC. If validated, PRO-C20 may be a novel biomarker for patients with solid tumors and can help understand the ECM biology of cancer.

An MMP-degraded and cross-linked fragment of type III collagen as a non-invasive biomarker of hepatic fibrosis resolution.

BACKGROUND AND AIMS: Liver fibrosis results from a prolonged wound healing response to continued injury with excessive production of extracellular proteins. In patients with chronic liver disease, the monitoring of liver fibrosis dynamics is of high interest. Whilst markers of fibrogenesis exist, markers of hepatic fibrosis resolution remain an unmet clinical need. Thus, we sought to develop an assay quantifying a circulating proteolytic fragment of cross-linked type III collagen as a biomarker of fibrolysis, testing its utility in two clinical cohorts of liver fibrosis of distinct aetiology and regressing endotype METHODS: We used a monoclonal antibody targeting the C-telopeptide of type III collagen following C-proteinase cleavage to develop and validate a neo-epitope-specific enzyme-linked immunosorbent assay (CTX-III). A potential fibrosis resolution marker, CTX-III, was measured in two clinical cohorts of patients with obesity-associated non-alcoholic fatty liver disease undergoing bariatric surgery or hepatitis C virus infection from a clinical trial study evaluating the anti-fibrotic effect of farglitazar. RESULTS: CTX-III was robust and specific for the targeted neo-epitope with good reproducibility in EDTA plasma. We assessed type III collagen remodelling using a panel of biomarkers, including a type III collagen formation marker (PRO-C3), degradation (C3M), and CTX-III (fibrolysis). Net fibrolysis was increased in patients with non-alcoholic fatty liver disease following bariatric surgery (p < .001). Moreover, net fibrolysis identified spontaneous fibrotic regressors from stable and progressors (p < .05 and p < .001) among hepatitis C virus infection patients. CONCLUSION: Circulating CTX-III as a marker of fibrolysis indicates the biomarker's beneficial use in assessing hepatic fibrosis resolution.

A Specific Calprotectin Neo-epitope [CPa9-HNE] in Serum from Inflammatory Bowel Disease Patients Is Associated with Neutrophil Activity and Endoscopic Severity.

BACKGROUND AND AIMS: Endoscopy and the use of faecal calprotectin [faecal CP] are among the least-favoured methods for assessing disease activity by inflammatory bowel disease [IBD] patients; the handling/processing of faecal samples is also impractical. Therefore, we sought to develop a novel neo-epitope serum calprotectin enzyme-linked immunosorbent assay [ELISA], CPa9-HNE, with the aim of quantifying neutrophil activity and neutrophil extracellular trap [NET]-osis and proposing a non-invasive method for monitoring disease activity in IBD patients. METHODS: In vitro cleavage was performed by mixing calprotectin [S100A9/S100A8] with human neutrophil elastase [HNE], and a novel HNE-derived calprotectin neo-epitope [CPa9-HNE] was identified by mass spectrometry for ELISA development. The CPa9-HNE ELISA was quantified in supernatants from ex vivo activated neutrophils and serum samples from patients with ulcerative colitis [UC, n = 43], Crohn's disease [CD, n = 93], and healthy subjects [HS, n = 23]. For comparison, faecal CP and MRP8/14 biomarkers were also measured. RESULTS: CPa9-HNE was specific for activated neutrophils ex vivo. Serum CPa9-HNE levels were 4-fold higher in CD [p <0.0001] and UC [p <0.0001] patients than in HS. CPa9-HNE correlated well with the Simple Endoscopic Score [SES]-CD score [r = 0.61, p <0.0001], MES [r = 0.46, p = 0.0141], and the full Mayo score [r = 0.52, p = 0.0013]. CPa9-HNE was able to differentiate between CD and UC patients in endoscopic remission and moderate/severe disease activity (CD: area under the curve [AUC] = 0.82 [p = 0.0003], UC: AUC = 0.87 [p = 0.0004]). The performance of CPa9-HNE was equipotent or slightly better than that of faecal CP. CONCLUSIONS: Serum CPa9-HNE levels were highly associated with CD and UC patients. CPa9-HNE correlated with the SES-CD score and the full Mayo score, indicating a strong association with disease activity.

A Serological Biomarker of Laminin Gamma 1 Chain Degradation Reflects Altered Basement Membrane Remodeling in Crohn's Disease and DSS Colitis.

BACKGROUND: The laminin gamma 1 chain (LMγ1) is abundant along the crypt-villus axis in the intestinal basement membrane. AIMS: We investigated whether a serological biomarker of laminin degradation was associated with disease activity in patients with Crohn's disease (CD) and in rats with dextran sulfate sodium (DSS)-induced colitis. METHODS: Serum samples from CD patients (n = 43), healthy subjects (n = 19), and Sprague Dawley rats receiving 5-6% DSS water for five days and regular drinking water for 11 days were included in this study. The LG1M biomarker, a neo-epitope degradation fragment of the LMγ1 chain generated by matrix metalloproteinases-9 (MMP-9), was measured in serum to estimate the level of laminin degradation. RESULTS: Serum LG1M was elevated in CD patients with active and inactive disease compared to healthy subjects (p < 0.0001). LG1M distinguished CD patients from healthy subjects, with an area under the curve (AUC) of 0.81 (p < 0.0001). Serum LG1M was decreased in DSS rats compared to controls 2 days after DSS withdrawal, and increased upon reversal of the disease. CONCLUSIONS: Increased serum LG1M in active and inactive CD patients supports the evidence of altered LM expression in both inflamed and non-inflamed tissue. Moreover, lower LG1M levels in the early healing phase of DSS-induced colitis may reflect ongoing mucosal repair.

Serologically assessed heat shock protein 47 is related to fibrosis stage in early compensated alcohol-related liver disease.

BACKGROUND AND AIMS: Heat shock protein (HSP)47 is a collagen-specific chaperone, essential for the correct formation of fibrillar procollagens. Collagen accumulation in the extracellular matrix (ECM) is a hallmark of fibrogenesis. The expression of HSP47 is proportional to the rate of collagen formation. Thus, HSP47 is a potential drug target for fibrotic diseases. We hypothesized that a C-terminal fragment of HSP47 (HSP47-C) could be quantified serologically and related to liver fibrosis stage. For this, a novel competitive enzyme-linked immunosorbent assay (ELISA) was developed. METHOD: An ELISA employing a monoclonal antibody targeting HSP47-C was developed and technically validated. The assay was evaluated in serum from a cross-sectional biopsy-controlled study of 281 patients with alcohol-related liver disease (ALD) and 50 gender, age and BMI matched healthy controls (HC). All liver biopsies from ALD patients were scored by one pathologist according to fibrosis stage (F0-4). RESULTS: The HSP47-C assay was technically robust and specific for the target sequence. HSP47-C was 39% higher in ALD patients (median 17.7 ng/mL, IQR 12.4-24.0 ng/mL) compared to HC (median 12.7 ng/mL, IQR 9.4-15.7 ng/mL, p < 0.0001). In addition, HSP47-C was elevated in patients with severe fibrosis (F3-4, median 22.8 ng/mL, IQR 17.5-33.3 ng/mL) compared to none-to-moderate fibrosis (F0-2, median 16.5 ng/mL, IQR 11.8-22.5 ng/mL) with an AUROC of 0.72 (p < 0.0001). HSP47-C also correlated with other liver disease parameters, albumin, bilirubin and aspartate transaminase. CONCLUSION: We developed a competitive ELISA for serological detection of HSP47-C. The study supports HSP47 as a potential marker of liver fibrosis in ALD.

Endotrophin and C6Ma3, serological biomarkers of type VI collagen remodelling, reflect endoscopic and clinical disease activity in IBD.

In inflammatory bowel disease (IBD), the chronic inflammation deeply affects the intestinal extracellular matrix. The aim of this study was to investigate if remodeling of the intestinal basement membrane type VI collagen was associated with pathophysiological changes in Crohn's disease (CD) and ulcerative colitis (UC). Serum from IBD patients (CD: n = 65; UC: n = 107; irritable bowel syndrome: n = 18; healthy subjects: n = 20) was investigated in this study. The serological biomarkers C6Ma3 (a matrix metalloproteinase (MMP) generated fragment of the type VI collagen α3 chain) and PRO-C6, also called endotrophin (the C-terminus of the released C5 domain of the type VI collagen α3 chain) were measured by ELISAs. Serum C6Ma3 was increased in CD patients with moderate to severe and mild endoscopically active disease compared to endoscopic remission (p = 0.002, p = 0.0048), respectively, and could distinguish endoscopically active disease from remission with an AUC of 1.0 (sensitivity: 100%, specificity: 100%) (p < 0.0001), which was superior to CRP. C6Ma3 was increased in CD patients with moderate to severe clinical disease compared to mild and remission (p = 0.04; p = 0.009). Serum PRO-C6, endotrophin, was increased in CD patients in clinically remission compared to mild disease (p = 0.04) and moderate to severe disease (p = 0.065). In UC, fecal calprotectin was the only marker that alone could distinguish both clinical and endoscopic active and inactive disease. Type VI collagen degradation of the α3 chain mediated by MMPs was increased in CD patients with endoscopically active disease, measured by the serological biomarker C6Ma3, which was able to distinguish endoscopically active from inactive CD.

Noninvasive prognostic biomarker potential of quantifying the propeptides of Type XI collagen alpha-1 chain (PRO-C11) in patients with pancreatic ductal adenocarcinoma.

Type XI collagen has been associated with tumor fibrosis and aggressiveness in patients with pancreatic ductal adenocarcinoma (PDAC). The propeptide on Type XI collagen is released into the circulation after proteolytic processing at either amino acid 253 or 511. This allows for a noninvasive biomarker approach to quantify Type XI collagen production. We developed two ELISA-based biomarkers, targeting the two enzymatic cleavage sites (PRO-C11-253 and PRO-C11-511). In a discovery cohort including serum from patients with PDAC (n = 39, Stages 1-4), chronic pancreatitis (CP, n = 12) and healthy controls (n = 20), PRO-C11-511, but not PRO-C11-253, was significantly upregulated in patients with PDAC and CP compared to healthy controls. Furthermore, PRO-C11-511 levels >75th percentile were associated with poor overall survival (OS) (HR, 95% CI: 3.40, 1.48-7.83). The PRO-C11-511 biomarker potential was validated in serum from 686 patients with PDAC. Again, high levels of PRO-C11-511 (>75th percentile) were associated with poor OS (HR, 95% CI: 1.68, 1.40-2.02). Furthermore, PRO-C11-511 remained significant after adjusting for clinical risk factors (HR, 95% CI: 1.50, 1.22-1.86). In conclusion, quantifying serum levels of Type XI collagen with PRO-C11-511 predicts poor OS in patients with PDAC. This supports that Type XI collagen is important for PDAC biology and that PRO-C11-511 has prognostic noninvasive biomarker potential for patients with PDAC.

The Citrullinated and MMP-degraded Vimentin Biomarker (VICM) Predicts Early Response to Anti-TNFα Treatment in Crohn's Disease.

BACKGROUND: In Crohn's disease (CD), 10% to 40% of patients do not respond to anti-tumor necrosis factor-α (TNFα) treatment. Currently, there are no biomarkers with adequate sensitivity to separate responders from nonresponders at an early stage. AIM: The aim of this study was to investigated whether early changes in the VICM (citrullinated and matrix metalloproteinase-degraded vimentin) biomarker were associated with response to anti-TNFα treatment in patients with CD. METHODS: Serum VICM levels were measured by ELISA in 2 independent cohorts of CD patients (n=42) treated with anti-TNFα (infliximab or adalimumab). Response was determined by achieving clinical remission (Harvey Bradshaw Index<5). RESULTS: Compared with baseline, VICM serum levels were reduced by anti-TNFα in the infliximab cohort (week 6 and 14) and in the adalimumab cohort (week 8). VICM was lower in the responders compared with the nonresponders [infliximab: week 6, P<0.05; area under the curve (AUC)=0.90; adalimumab: week 1, P<0.01 (AUC=0.91), and week 8, P<0.05 (AUC=0.86)], and were able to predict response to treatment after 1 week of treatment with an odds ratio of 42.5. CONCLUSIONS: The VICM biomarker was time dependently reduced in CD patients responding to anti-TNFα treatment. We suggest that VICM may be used as a marker for monitoring early response to anti-TNFα in patients with CD.

Serological Biomarkers of Tissue Turnover Identify Responders to Anti-TNF Therapy in Crohn's Disease: A Pilot Study.

INTRODUCTION: Anti-tumor necrosis factor (TNF) therapy is effective in inducing remission in Crohn's disease in 60% of patients. No serological biomarkers are available, which can predict response to anti-TNF. We aimed to investigate serological markers of collagen turnover reflecting tissue inflammation as predictors of response to anti-TNF. METHODS: In 2 retrospective observational cohorts, markers for matrix metalloproteinase-degraded type III and IV collagens (C3M and C4M, respectively) and for formation of type III and IV collagens (PRO-C3 and PRO-C4, respectively) were measured in serum and compared with standard C-reactive protein in patients with active Crohn's disease who started infliximab (IFX, n = 21) or adalimumab (ADA, n = 21). Disease activity was classified by the Harvey-Bradshaw index (active disease ≥5); response was defined as clinical remission. RESULTS: Seventeen patients (81%) treated with IFX were in remission at week 14; 15 patients (71%) treated with ADA were in remission at week 8. Serum C4M at baseline was increased in nonresponders compared with responders (IFX: 35.0 ± 2.4 vs 23.2 ± 2.6, P = 0.04, ADA: 53.0 ± 3.2 vs 34.1 ± 2.8, P = 0.006). C4M levels at baseline predicted response in both cohorts (IFX: odds ratio 39 [95% confidence interval, 2.4-523.9] P = 0.02, cutoff 35.2 nmol/L; ADA: odds ratio 26 [95% confidence interval, 1.8-332.5], P = 0.01, cutoff 46.9 nmol/L). C-reactive protein was not able to predict response to anti-TNF. DISCUSSION: Response to anti-TNF therapy within the first 14 weeks of treatment can be predicted based on baseline levels of basement membrane marker C4M. This marker could be used as biomarker for response to anti-TNF and could aid in early therapy decision making. Validation in larger well-defined cohorts is needed.

A novel biomarker of MMP-cleaved prolargin is elevated in patients with psoriatic arthritis.

Psoriatic arthritis (PsA) is a chronic musculoskeletal inflammatory disease found in up to 30% of psoriasis patients. Prolargin-an extracellular matrix (ECM) protein present in cartilage and tendon-has been previously shown elevated in serum of patients with psoriasis. ECM protein fragments can reflect tissue turnover and pathological changes; thus, this study aimed to develop, validate and characterize a novel biomarker PROM targeting a matrix metalloproteinase (MMP)-cleaved prolargin neo-epitope, and to evaluate it as a biomarker for PsA. A competitive ELISA was developed with a monoclonal mouse antibody; dilution- and spiking-recovery, inter- and intra-variation, and accuracy were evaluated. Serum levels were evaluated in 55 healthy individuals and 111 patients diagnosed with PsA by the CASPAR criteria. Results indicated that the PROM assay was specific for the neo-epitope. Inter- and intra- assay variations were 11% and 4%, respectively. PROM was elevated (p = 0.0003) in patients with PsA (median: 0.24, IQR: 0.19-0.31) compared to healthy controls (0.18; 0.14-0.23) at baseline. AUROC for separation of healthy controls from PsA patients was 0.674 (95% CI 0.597-0.744, P < 0.001). In conclusion, MMP-cleaved prolargin can be quantified in serum by the PROM assay and has the potential to separate patients with PsA from healthy controls.

Serum Type XIX Collagen is Significantly Elevated in Non-Small Cell Lung Cancer: A Preliminary Study on Biomarker Potential.

Type XIX collagen is a poorly characterized collagen associated with the basement membrane. It is abnormally regulated during breast cancer progression and the NC1 (XIX) domain has anti-tumorigenic signaling properties. However, little is known about the biomarker potential of collagen XIX in cancer. In this study, we describe a competitive ELISA, named PRO-C19, targeting the C-terminus of collagen XIX using a monoclonal antibody. PRO-C19 was measured in serum of patients with a range of cancer types and was elevated in non-small cell lung cancer (NSCLC) (p < 0.0001), small cell lung cancer (p = 0.0081), breast (p = 0.0005) and ovarian cancer (p < 0.0001) compared to healthy controls. In a separate NSCLC cohort, PRO-C19 was elevated compared to controls when evaluating adenocarcinoma (AD) (p = 0.0003) and squamous cell carcinoma (SCC) (p < 0.0001) patients but was not elevated in chronic obstructive pulmonary disease patients. SCC also had higher PRO-C19 levels than AD (p = 0.0457). PRO-C19 could discriminate between NSCLC and healthy controls (AUROC:0.749 and 0.826 for AD and SCC, respectively) and maintained discriminatory performance in patients of tumor stages I+II (AUROC:0.733 and 0.818 for AD and SCC, respectively). Lastly, we confirmed the elevated type XIX collagen levels using gene expression data from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) initiatives. In conclusion, type XIX collagen is released into circulation and is significantly elevated in the serum of cancer patients and PRO-C19 shows promise as a cancer biomarker.

Mechanisms of vascular permeability and remodeling associated with hemarthrosis in factor VIII-deficient mice.

BACKGROUND: Vascular remodeling associated with hemophilic arthropathy (HA) may contribute to bleed propagation, but the mechanisms remain poorly understood. OBJECTIVES: To explore molecular mechanisms of HA and the effects of hemostasis correction on synovial vascular remodeling after joint injury in hypocoagulable mice. METHODS: Factor VIII (FVIII)-deficient mice +/- FVIII treatment and hypocoagulable wild-type mice (Hypo BALB/c) were subjected to subpatellar puncture. Hypo BALB/c mice were treated with warfarin and anti-FVIII before injury, after which warfarin was continued for 2 weeks or reversed +/- continuous anti-FVIII until harvest. Synovial vascularity was analyzed at baseline and 2 to 4 weeks post injury by histology, musculoskeletal ultrasound with power Doppler (microvascular flow), and Evans blue extravasation (vascular permeability). Synovial gene expression and systemic markers of vascular collagen turnover were studied in FVIII-deficient mice by RNA sequencing and enzyme-linked immunosorbent assay. RESULTS: Vascular changes occurred in FVIII-deficient and Hypo BALB/c mice after injury with minimal effect of hemostasis correction. Increased vascular permeability was only significant in FVIII-deficient mice, who exhibited more pronounced vascular remodeling than Hypo BALB/c mice despite similar bleed volumes. FVIII-deficient mice exhibited a strong transcriptional response in synovium that was only partially affected by FVIII treatment and involved genes relating to angiogenesis and extracellular matrix remodeling, with vascular collagen turnover markers detected systemically. CONCLUSIONS: Intact hemostasis at the time of hemarthrosis and during healing are both critical to prevent vascular remodeling, which appears worse with severe and prolonged FVIII deficiency. Unbiased RNA sequencing revealed potential targets for intervention and biomarker development to improve management of HA.

Serological Assessment of the Quality of Wound Healing Processes in Crohn's Disease.

BACKGROUND AND AIMS: Crohn's disease (CD) is a chronic inflammatory condition characterized by continuous mucosal damage and ongoing wound healing of the intestines. The fibrinolytic system is involved in early parts of the wound healing process. Fibrin is a key mediator of primary blood clot formation and is formed by cross-linking of fibrinogen. To gain insights into the dynamics of wound healing in CD patients we investigated the conversion of fibrinogen into fibrin by the pro-peptide FPA, the amount of factor XIII cross-linked fibrin and total fibrin clot. METHODS: Serum samples of 35 CD patients, 15 non-inflammatory bowel disease (non-IBD) patients and 39 age-matched healthy controls were analyzed for three novel neo-epitope markers: D-fragment and D-dimer, reflecting the degradation of total fibrin clot and factor XIII cross-linked fibrin, as well as FPA, reflecting synthesis of fibrin. RESULTS: Crohn's disease patients had a significantly lower D-dimer level (p=0.0001) compared to healthy controls. Crohn's disease and non-IBD patients had a significantly higher level of FPA (p<0.0001) and D-fragment/D-dimer ratio (p<0.0001 and p=0.02). FPA, D-dimer and D-fragment/D-dimer ratio could distinguish CD patients from healthy controls with area under the curve of 0.92 (95% CI 0.83-0.97), 0.78 (95% CI 0.67-0.87) and 0.85 (95% CI 0.75-0.93), respectively. CONCLUSION: Wound healing parameters were clearly changed in CD patients. FPA levels were higher in CD patients as compared to healthy controls, indicating more ongoing wound healing. D-dimer levels were lower in CD patients than in healthy controls, indicating impaired wound healing due to poor quality of factor XIII cross-linked fibrin and clot resolution.

Type IV collagen turnover is predictive of mortality in COPD: a comparison to fibrinogen in a prospective analysis of the ECLIPSE cohort.

BACKGROUND: Identifying subjects with chronic obstructive pulmonary disease (COPD) at high risk of exacerbation and mortality is key to aid individual management of COPD. The only FDA approved blood-based drug development biomarker for patients at high risk of mortality, is plasma fibrinogen. In this study, we benchmarked two biomarkers of basement membrane remodeling, a characteristic of COPD, against plasma fibrinogen alone and as a combination. The biomarkers of basement membrane remodeling are two neoepitopes from of the alpha 3 chain of type IV collagen (COL4A3). MATERIALS AND METHODS: COL4A3 degradation was assessed by the biomarkers C4Ma3 and tumstatin (TUM) in year 1 plasma samples in 984 COPD subjects, 95 non-smoking controls and 95 smoking controls from the Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE) cohort. They were measured by competitive ELISA using monoclonal antibodies recognizing two specific MMP-generated cleavage site within COL4A3. The level of fibrinogen was previously assessed in year 1 plasma. RESULTS: In COPD subjects, plasma C4Ma3 levels were significantly correlated with plasma fibrinogen levels (0.389 (P < 0.0001)). Cox proportional-hazards regression adjusted for relevant confounders showed that high levels of plasma C4Ma3, but not TUM, were related to a higher risk of mortality (hazard ratio 5.12 (95% CI 2.28-11.50), P < 0.0001). High levels of plasma fibrinogen were not associated with all-cause mortality in this subpopulation, contradictory to published results. Whereas plasma C4Ma3 multiplied by fibrinogen showed to be related to a higher risk of mortality (hazard ratio 5.74 (95% CI 2.65-12.41), P < 0.0001). Plasma C4Ma3 levels were related to the number of hospitalizations due to COPD exacerbations in the year before study start (P = 0.0375). Fibrinogen levels were related to hospitalized exacerbations prior to study start (P = 0.0058) and were also related to future exacerbations (P < 0.0001). CONCLUSION: We compared herein fibrinogen, C4Ma3 and TUM as biomarkers for COPD prognosis. Fibrinogen was related to future exacerbation, whereas C4Ma3 and the combination of C4Ma3 with fibrinogen were superior to fibrinogen alone in predicting mortality. This pilot study suggests that the assessment of plasma C4Ma3 could be important for identifying COPD patients with a poor prognosis. TRIAL REGISTRATION: NCT00292552 , GSK Study No. SCO104960.

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

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.

GPDPLQ1237-A Type II Collagen Neo-Epitope Biomarker of Osteoclast- and Inflammation-Derived Cartilage Degradation in vitro.

C-telopeptide of type II collagen (CTX-II) has been shown to be a highly relevant biomarker of cartilage degradation in human rheumatic diseases, if measured in synovial fluid or urine. However, serum or plasma CTX-II have not been demonstrated to have any clinical utility to date. Here, we describe the GPDPLQ1237 ELISA which targets the EKGPDPLQ↓ neo-epitope, an elongated version of the CTX-II neo-epitope (EKGPDP↓), speculated to be a blood-precursor of CTX-II generated by the cysteine protease cathepsin K. Human osteoclast cartilage resorption cultures as well as oncostatin M and tumour necrosis factor α-stimulated bovine cartilage explant cultures were used to validate GPDPLQ1237 biologically by treating the cultures with the cysteine protease inhibitor E-64 and/or the matrix metalloproteinase (MMP) inhibitor GM6001 to assess the potential contributions of these two protease classes to GPDPLQ1237 release. Cartilage resorption-derived GPDPLQ1237 release was inhibited by E-64 (72.1% inhibition), GM6001 (75.5%), and E-64/GM6001 (91.5%), whereas CTX-II release was inhibited by GM6001 (87.0%) but not by E-64 (5.5%). Cartilage explant GPDPLQ1237 and CTX-II release were both fully inhibited by GM6001 but were not inhibited by E-64. No clinically relevant GPDPLQ1237 reactivity was identified in human serum, plasma, or urine from healthy donors or arthritis patients. In conclusion, the GPDPLQ1237 biomarker is released during osteoclast-derived cysteine protease- and MMP-mediated cartilage degradation in vitro, whereas CTX-II release is mediated by MMPs and not by cysteine proteases, as well as from MMP-mediated cartilage degradation under a pro-inflammatory stimulus. These findings suggest that GPDPLQ1237 may be relevant in diseases with pathological osteoclast activity and cartilage degradation. Further studies are required to validate the neo-epitope in human samples.

Ulcerative colitis, Crohn's disease, and irritable bowel syndrome have different profiles of extracellular matrix turnover, which also reflects disease activity in Crohn's disease.

BACKGROUND: Increased protease activity is a key pathological feature of inflammatory bowel disease (IBD). However, the differences in extracellular matrix remodelling (ECM) in Crohn's disease (CD) and ulcerative colitis (UC) are not well described. An increased understanding of the inflammatory processes may provide optimized disease monitoring and diagnostics. We investigated the tissue remodelling in IBD and IBS patients by using novel blood-based biomarkers reflecting ECM remodelling. METHODS: Five ECM biomarkers (VICM, BGM, EL-NE, C5M, Pro-C5) were measured by competitive ELISAs in serum from 72 CD patients, 60 UC patients, 22 patients with irritable bowel syndrome (IBS), and 24 healthy donors. One-way analysis of variance, Mann-Whitney U-test, logistic regression models, and receiver operator characteristics (ROC) curve analysis was carried out to evaluate the diagnostic accuracy of the biomarkers. RESULTS: The ECM remodelling was significantly different in UC compared to CD. The best biomarker combination to differentiate UC from CD and colonic CD was BGM and VICM (AUC = 0.98, P<0.001; AUC = 0.97, P<0.001), and the best biomarker combination to differentiate IBD from IBS patients were BGM, EL-NE, and Pro-C5 (AUC = 0.8, P<0.001). When correcting for the use of immunosuppressant and elevated CRP levels (CRP>5mg/mL), correlation of Pro-C5 (r = 0.36) with CDAI was slightly improved compared to CRP (r = 0.27) corrected for the use of immunosuppressant. Furthermore, BGM and EL-NE biomarkers were highly associated with colon inflammation in CD patients. CONCLUSION: ECM fragments of tissue remodelling in IBD affect UC and CD differently, and may aid in differentiating IBD from IBS (EL-NE, BGM, Pro-C5), and UC from CD patients (BGM, VICM). Formation of type V collagen is related to the level of inflammation in CD and may reflect disease activity in CD.

Bimodal role of NADPH oxidases in the regulation of biglycan-triggered IL-1ß synthesis.

Biglycan, a ubiquitous proteoglycan, acts as a danger signal when released from the extracellular matrix. As such, biglycan triggers the synthesis and maturation of interleukin-1ß (IL-1ß) in a Toll-like receptor (TLR) 2-, TLR4-, and reactive oxygen species (ROS)-dependent manner. Here, we discovered that biglycan autonomously regulates the balance in IL-1ß production in vitro and in vivo by modulating expression, activity and stability of NADPH oxidase (NOX) 1, 2 and 4 enzymes via different TLR pathways. In primary murine macrophages, biglycan triggered NOX1/4-mediated ROS generation, thereby enhancing IL-1ß expression. Surprisingly, biglycan inhibited IL-1ß due to enhancement of NOX2 synthesis and activation, by selectively interacting with TLR4. Synthesis of NOX2 was mediated by adaptor molecule Toll/IL-1R domain-containing adaptor inducing IFN-ß (TRIF). Via myeloid differentiation primary response protein (MyD88) as well as Rac1 activation and Erk phosphorylation, biglycan triggered translocation of the cytosolic NOX2 subunit p47(phox) to the plasma membrane, an obligatory step for NOX2 activation. In contrast, by engaging TLR2, soluble biglycan stimulated the expression of heat shock protein (HSP) 70, which bound to NOX2, and consequently impaired the inhibitory function of NOX2 on IL-1ß expression. Notably, a genetic background lacking biglycan reduced HSP70 expression, rescued the enhanced renal IL-1ß production and improved kidney function of Nox2(-/y) mice in a model of renal ischemia reperfusion injury. Here, we provide a novel mechanism where the danger molecule biglycan influences NOX2 synthesis and activation via different TLR pathways, thereby regulating inflammation severity. Thus, selective inhibition of biglycan-TLR2 or biglycan-TLR4 signaling could be a novel therapeutic approach in ROS-mediated inflammatory diseases.