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

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.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.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.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

Evaluation of serum ARGS neoepitope as an osteoarthritis biomarker using a standardized model for exercise-induced cartilage extra cellular matrix turnover

Summary: Objective: To propose a standardized model for exercise-induced cartilage turnover and investigate residual levels and dynamics of biomarker serum ARGS (sARGS) in primary osteoarthritis (OA) patients and a supportive group of young healthy subjects. Method: The trial is a randomized, cross-over, exploratory study with interventions of exercise and inactivity. 20 subjects with knee OA, as well as 20 young healthy subjects (mean age 25.7 years (range; 19–30), 50% male), underwent cycling, running and resting interventions on separate days one week apart. Blood samples were taken at baseline, immediately, 1, 2, 3 and 24 h after activity start. sARGS was measured by sandwich ELISA. Results: Intraclass correlation between visits were 0.97 and 0.77 for the OA and healthy group, respectively. An acute drop in sARGS in response to high-intensity exercise was observed in both groups. Minute acute sARGS increase was observed in OA subjects in response to moderate intensity running and cycling, which normalized within 24 h. In healthy subjects an acute drop in sARGS was seen immediately after running, but not cycling, and no other changes were observed. A negative correlation between baseline Kellgren-Lawrence (KL) grade and baseline sARGS (r = −0.69, p = 0.002) in OA was found. A negative correlation between age and sARGS was found in healthy subjects (r = −0.67, p = <0.002). Conclusion: sARGS sensitivity to physical activity is considered low and sARGS is a reproducible and stable marker. Minute acute increases in sARGS were observed in the hours following moderate intensity exercise

Suppression of MMP activity in bovine cartilage explants cultures has little if any effect on the release of aggrecanase-derived aggrecan fragments

<p>Abstract</p> <p>Background</p> <p>Progressive loss of articular cartilage is a central hallmark in many joint disease, however, the relative importance of individual proteolytic pathways leading to cartilage erosion is at present unknown. We therefore investigated the time-dependant release <it>ex vivo </it>of MMP- and aggrecanase-derived fragments of aggrecan and type II collagen into the supernatant of bovine cartilage explants cultures using neo-epitope specific immunoassays, and to associate the release of these fragments with the activity of proteolytic enzymes using inhibitors.</p> <p>Findings</p> <p>Bovine cartilage explants were cultured in the presence or absence of the catabolic cytokines oncostatin M (OSM) and tumor necrosis factor alpha (TNFα). In parallel, explants were co-cultured with protease inhibitors such as GM6001, TIMP1, TIMP2 and TIMP3. Fragments released into the supernatant were determined using a range of neo-epitope specific immunoassays; (1) sandwich ³⁴²FFGVG-G2 ELISA, (2) competition NITEGE³⁷³ELISA (3) sandwich G1-NITEGE³⁷³ELISA (4) competition ³⁷⁴ARGSV ELISA, and (5) sandwich ³⁷⁴ARGSV-G2 ELISA all detecting aggrecan fragments, and (6) sandwich CTX-II ELISA, detecting C-telopeptides of type II collagen. We found that (1) aggrecanase-derived aggrecan fragments are released in the early (day 2-7) and mid phase (day 9-14) into the supernatant from bovine explants cultures stimulated with catabolic cytokines, (2) the release of NITEGE³⁷³neo-epitopes are delayed compared to the corresponding ³⁷⁴ARGSV fragments, (3) the MMP inhibitor GM6001 did not reduce the release of aggrecanase-derived fragment, but induced a further delay in the release of these fragments, and finally (4) the MMP-derived aggrecan and type II collagen fragments were released in the late phase (day 16-21) only.</p> <p>Conclusion</p> <p>Our data support the model, that aggrecanases and MMPs act independently in the processing of the aggrecan molecules, and furthermore that suppression of MMP-activity had little if any effect on the quantity of aggrecanase-derived fragments released from explants cultures.</p

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

Background: In Crohn's disease (CD), 10% to 40% of patients do not respond to anti-tumor necrosis factor- (TNF) 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-TNF 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-TNF (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-TNF 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-TNF treatment. We suggest that VICM may be used as a marker for monitoring early response to anti-TNF in patients with CD

Biochemical markers of ongoing joint damage in rheumatoid arthritis - current and future applications, limitations and opportunities

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease associated with potentially debilitating joint inflammation, as well as altered skeletal bone metabolism and co-morbid conditions. Early diagnosis and aggressive treatment to control disease activity offers the highest likelihood of preserving function and preventing disability. Joint inflammation is characterized by synovitis, osteitis, and/or peri-articular osteopenia, often accompanied by development of subchondral bone erosions, as well as progressive joint space narrowing. Biochemical markers of joint cartilage and bone degradation may enable timely detection and assessment of ongoing joint damage, and their use in facilitating treatment strategies is under investigation. Early detection of joint damage may be assisted by the characterization of biochemical markers that identify patients whose joint damage is progressing rapidly and who are thus most in need of aggressive treatment, and that, alone or in combination, identify those individuals who are likely to respond best to a potential treatment, both in terms of limiting joint damage and relieving symptoms. The aims of this review are to describe currently available biochemical markers of joint metabolism in relation to the pathobiology of joint damage and systemic bone loss in RA; to assess the limitations of, and need for additional, novel biochemical markers in RA and other rheumatic diseases, and the strategies used for assay development; and to examine the feasibility of advancement of personalized health care using biochemical markers to select therapeutic agents to which a patient is most likely to respond

Relevance of Biomarkers in Serum vs. Synovial Fluid in Patients with Knee Osteoarthritis

The association between structural changes and pain sensation in osteoarthritis (OA) remains unclear. Joint deterioration in OA leads to the release of protein fragments that can either systemically (serum) or locally (synovial fluid; SF) be targeted as biomarkers and describe structural changes and potentially pain. Biomarkers of collagen type I (C1M), type II (C2M), type III (C3M), type X (C10C), and aggrecan (ARGS) degradation were measured in the serum and SF of knee OA patients. Spearman’s rank correlation was used to assess the correlation of the biomarkers’ levels between serum and SF. Linear regression adjusted for confounders was used to evaluate the associations between the biomarkers’ levels and clinical outcomes. The serum C1M levels were negatively associated with subchondral bone density. The serum C2M levels were negatively associated with KL grade and positively associated with minimum joint space width (minJSW). The C10C levels in SF were negatively associated with minJSW and positively associated with KL grade and osteophyte area. Lastly, the serum C2M and C3M levels were negatively associated with pain outcomes. Most of the biomarkers seemed to mainly be associated with structural outcomes. The overall biomarkers of extracellular matrix (ECM) remodeling in serum and SF may provide different information and reflect different pathogenic processes

Biomarkers of neutrophil activity and extracellular matrix turnover predict long-term response to vedolizumab in patients with Crohn's disease

Background Crohn‘s disease (CD) is a form of inflammatory bowel disease characterized by high infiltration of immune cells into the intestinal tissue, resulting in increased proteolytic mediated extracellular matrix (ECM) remodeling. Disease management has improved with the use of biologics such as vedolizumab (VEDO). However, considering the high rate of primary non-response to VEDO, there is an unmet need for predictive serum biomarkers capable of determining response to treatment prior to its initiation. This study investigated whether biomarkers of neutrophil activity, mucosal damage, and ECM remodeling could serve as non-invasive tools for predicting long-term response to VEDO in patients with CD. Methods Serum biomarkers of human neutrophil elastase (HNE)-derived fragment of calprotectin (CPa9-HNE [serum calprotectin]) and matrix metalloproteinase (MMP)-derived fragments of type I (C1M), III (C3M), IV (C4M), type III collagen formation (PRO-C3), basement membrane turnover (PRO-C4) and T-cell activity (C4G), were measured using protein fingerprint assays in patients with CD (n=32) before VEDO therapy initiation. The ratio C4M/C4G (myeloid/lymphoid mediated degradation) was computed. Long-term response was defined as the continuation of treatment beyond one year after the start of therapy. Baseline biomarker levels were compared between responders and non-responders using Mann-Whitney U-tests, and area under the curve (AUC) values were generated using receiver operating characteristics (ROC) statistics. Biomarker levels were divided into tertiles and chi-square tests were used to investigate the relationship between tertiles and response proportions. Results Biomarkers CPa9-HNE, C1M, C3M, C4M, PRO-C3, C3M/PRO-C3, and C4M/C4G were significantly increased at baseline in non-responders compared with responders (all P<0.05). All markers were able to predict response to VEDO at baseline (AUC [95% CI]: CPa9-HNE 0.81 [0.66–0.96]; C1M 0.85 [0.75–0.98]; C3M 0.79 [0.62–0.95]; C4M 0.77 [0.6–0.93]; C3M/PRO-C3 0.78 [0.6–0.95]; C4M/C4G 0.74 [0.56–0.92] all P<0.05). Proportions of long-term VEDO users were highest in the first tertiles for all the markers (73–91%) and decreased in a concentration-dependent manner across the second and third tertiles, indicating that patients with the lowest concentrations of these markers less frequently discontinued treatment at one year after initiation (Figure 1). Conclusion Baseline levels of serum biomarkers for neutrophil activity (CPa9-HNE [serum calprotectin]) and mucosal damage (C1M, C3M, C4M, C4G, PRO-C4, and PRO-C3) could predict long-term response to VEDO in patients with CD. Therefore, these biomarkers could aid in early decision making concerning treatment with vedolizumab in patients with CD