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

Abstract

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.

Extracellular matrix remodeling proteins as biomarkers for clinical assessment and treatment outcomes in eosinophilic esophagitis

“…Our data demonstrated elevated fibrolysis in patients with a ‘severe fibrotic endotype,’ indicating an increased turnover of mature cross-linked type III collagen potentially due to excessive collagen deposition. Previous data of CTX-III in hepatitis C-associated liver fibrosis demonstrated a correlation of this biomarker with regressive liver fibrosis [ 39 ]. Patients with severe fibrosis could achieve fibrosis regression due to the resolution of the fibrotic extracellular matrix resulting from the high turnover indicated by elevated serum CTX-III.…”

Lot-to-Lot Variance in Immunoassays—Causes, Consequences, and Solutions

“…The primary impurities detected in recombinant IgG include a single light chain (LC), a combination of two heavy chains and one light chain (2H1L), two heavy chains (2H), and nonglycosylated IgG. In recent experiments conducted in our laboratory, we observed a significant disparity when exchanging a monoclonal antibody directed towards CTX-III [14] from hybridoma to recombinant antibody, despite their identical amino acid sequences. We found that the recombinant antibody led to substantially lower sensitivity and maximal signals in the CTX-III assay when compared to the hybridoma antibody (as illustrated in Table 2).…”

Fibroblast Activation Protein (FAP)-Mediated Cleavage of Type III Collagen Reveals Serum Biomarker Potential in Non-Small Cell Lung Cancer and Spondyloarthritis

“…Type III collagen is primarily derived from activated fibroblasts and increased formation has been shown for CAFs [ 31 , 32 ]. The increased expression, maturation, and remodeling of type III collagen have been associated with cancer and multiple fibrotic disorders [ 31 , 33 , 34 , 35 ]. Multiple MMPs have been shown to cleave native type III collagen including MMP-1, MMP-8, MMP-9, MMP-12, and MMP-13 [ 33 , 36 , 37 , 38 ].…”

“…The increased expression, maturation, and remodeling of type III collagen have been associated with cancer and multiple fibrotic disorders [ 31 , 33 , 34 , 35 ]. Multiple MMPs have been shown to cleave native type III collagen including MMP-1, MMP-8, MMP-9, MMP-12, and MMP-13 [ 33 , 36 , 37 , 38 ]. Zhang et al have investigated FAP cleavage in the ECM using degradomics based on terminal amine isotopic labelling of substrates (TAILS) in mice and identified novel cleavage sites that could potentially be used to reflect FAP activity [ 24 ].…”