P4NP 7S Research Articles

Association Between the Liver Fibrosis Markers and Scores, and Hemodynamic Congestion Assessed by Peripheral Venous Pressure in Patients With Acute Heart Failure.

Background Peripheral venous pressure (PVP) has been shown to be a reliable surrogate for right atrial pressure in assessing congestion in patients with heart failure (HF). Liver fibrosis markers and scores can be useful in assessing organ injury in patients with acute HF. This study aimed to investigate the association of liver fibrosis markers and scores with PVP in patients with acute HF. Methods and Results The 7S domain of the collagen type IV N-terminal propeptide (P4NP 7S), aspartate aminotransferase-to-platelet ratio index, fibrosis-4, and nonalcoholic fatty liver disease fibrosis score were determined along with PVP measurements before discharge in 229 patients with acute HF. The strongest correlation with PVP was found for P4NP 7S (Pearson r=0.40). Patients with high P4NP 7S levels (≥median [6.2 ng/mL]) had an increased risk of cardiovascular death or HF hospitalization (adjusted hazard ratio [HR], 1.80 [95% CI, 1.09-3.04], P=0.02). The concomitant high PVP (≥mean [8 mm Hg])/high P4NP 7S group, in contrast to the high PVP/low P4NP 7S or low PVP/high P4NP 7S group, had a significant risk relative to the low PVP/low P4NP 7S group for cardiovascular death or HF hospitalization (adjusted HR, 2.63 [95% CI, 1.43-5.05], P=0.002). A sustained elevation in PVP for 1 month postdischarge was associated with a persistent increase in P4NP 7S. Conclusions The study demonstrated the relationship between the liver fibrosis marker P4NP 7S and congestion. PVP and P4NP 7S could be useful for assessing congestion-related organ injury and predicting prognosis in patients with acute HF.

Relationship between atrial fibrillation and a liver fibrogenesis marker in patients with acute heart failure

BackgroundHemodynamic disturbance in heart failure (HF) induces extra-cardiac organ injury. Atrial fibrillation (AF) is common in patients with HF. The relationship between AF and organ injury in HF remains unclear. We investigated the relationship between AF and the liver fibrosis marker, type IV collagen 7S (P4NP 7S) in patients with HF. Methods and resultsFrom a pooled dataset of 3 observational cohorts of hospitalized HF, 720 patients in whom P4NP 7S was measured before discharge were included. Median P4NP 7S were 5.1, 5.3, and 6.2 ng/mL in the sinus rhythm (SR) (n = 368), paroxysmal AF (n = 67), and persistent AF (n = 285) groups, respectively (P < 0.001). In the multiple linear regression analysis, the significant association with P4NP 7S was found for persistent AF (P < 0.001). The cumulative 1-year incidence of the primary composite endpoint of cardiac death and HF hospitalization were 27.6, 24.1, and 34.5% in the SR, paroxysmal AF, and persistent AF groups, respectively (Log-rank P = 0.07) and 25.3 and 34.5% in the low (below median) and high P4NP 7S groups, respectively (Log-rank P = 0.005). The adjusted risks of persistent AF versus SR and high P4NP 7S versus low P4NP 7S for the primary endpoint were 1.38 (95% confidence interval 1.02–1.89) and 1.52 (1.14–2.03), respectively. When patients were divided based on a combination of AF and P4NP 7S, concomitant persistent AF and high P4NP 7S portended a dismal prognosis. ConclusionAF is associated with an increase in the liver fibrosis marker. Co-presence of persistent AF and P4NP 7S may portend adverse clinical outcomes.

Abstract 13304: Liver Dispersion Predicts Adverse Outcomes in Patients With Heart Failure

Background: It has been recently reported that liver stiffness assessed by transient elastography reflects right atrial pressure (RAP), and is associated with worse outcome in patients with heart failure (HF). However, the relationship between liver dispersion (LD, a novel indicator of liver viscosity) determined by abdominal ultrasonography and RAP, and prognostic impacts of LD on HF patients have not been fully examined. We aimed to clarify associations of LD with parameters of liver functional test (LFT) and right-heart catheterization (RHC), and cardiac event such as cardiac death and worsening HF in patients with HF. Methods and Results: We performed abdominal ultrasonography, LFT, RHC, and followed up cardiac events including cardiac death and unplanned hospitalization due to HF in patients with HF (n=157). We examined associations of LD with parameters of LFT and RHC. There were significant correlations between LD and circulating levels of gamma-glutamyl transferase (R=0.197, P=0.018), cholinesterase (R=-0.301, P=0.001), and 7S domain of collagen type IV (P4NP 7S, a marker of fibrosis, R=0.334, P&lt;0.001), but not with RAP (R=0.067, P=0.514) or cardiac index (R=-0.038, P=0.667). During the follow up period (median 305 days), 6 cardiac deaths and 18 unplanned hospitalization due to HF occurred. In the Kaplan-Meier analysis ( Figure ), cardiac event rate was significantly higher in the high LD group (LD ≥10.0 (m/s)/kHz, n=79) than in the low LD group (LD &lt; 10.0 (m/s)/kHz, n=78; log-rank, P=0.007). In the multivariable Cox proportional hazard analysis, high LD was found to be an independent predictor of cardiac event (hazard ratio 3.274, 95% confidence interval 1.203-8.912, P=0.020). Conclusions: LD assessed by abdominal ultrasonography reflects liver fibrosis rather than liver congestion, and is associated with adverse prognosis in HF patients.

Utility of collagen-derived peptides as markers of organ injury in patients with acute heart failure

ObjectiveThis study aims to investigate the time-dependent prognostic utility of two fibrosis markers representing organ fibrogenesis (N-terminal propeptide of procollagen III (PIIINP) and type IV collagen 7S (P4NP 7S)) in...

P2623Measurement of liver fibrosis marker: type IV collagen 7S among patients with acute heart failure and its relationship with the Enhanced Liver Fibrosis (ELF) score

Abstract Background Hemodynamic disturbance in acute heart failure (HF) can cause injury to extra-cardiac organs such as the liver. Organ injury in HF might evoke a profibrotic response, which could adversely affect the prognosis. Methods Among 189 patients with acute HF, we simultaneously determined the liver fibrosis marker, type IV collagen 7S (P4NP 7S) and the Enhanced Liver Fibrosis (ELF) Score consisting of tissue inhibitor of metalloproteinases 1 (TIMP-1), amino-terminal propeptide of type III procollagen (PIIINP) and hyaluronic acid (HA) on admission and at discharge. Results During hospitalization, P4NP 7S and ELF score significantly decreased from 7.1 ng/mL to 6.1 ng/mL (P&lt;0.001) and 10.39 to 10.13 (P&lt;0.001), respectively. P4NP 7S and ELF score were correlated with each other on admission (r=0.4, P&lt;0.001) and at discharge (r=0.4, P&lt;0.001). %Change of (Δ) P4NP 7S during hospitalization was correlated with ΔBNP and ΔELF score (r=0.3, P&lt;0.001 and r=0.4, P&lt;0.001, respectively). Among the components of ELF score, PIIINP and HA were correlated with P4NP 7S on admission (r=0.5, P&lt;0.001 and r=0.3, P&lt;0.001, respectively) and at discharge (r=0.4, P&lt;0.001 and r=0.3, P&lt;0.001, respectively). ΔP4NP 7S was also correlated with ΔTIMP-1, ΔPIIINP and ΔHA (r=0.3, P&lt;0.001, r=0.4, P&lt;0.001 and r=0.3, P&lt;0.001, respectively). Each patient was followed up up to 365 days after discharge. 69 patients died or were hospitalized for HF. When the patients were divided into two groups according to the median value of each marker at discharge, the cumulative 1-year incidences of all cause death or HF hospitalization were 32.0% and 45.5% in P4NP 7S-low and P4NP 7S-high group, respectively (log-rank P=0.051) and 43.2% and 34.9% in ELF score-low and ELF score-high group, respectively (log-rank P=0.44). After adjustment by the clinically relevant factors including age, sex, hemoglobin, sodium and left ventricular ejection fraction, P4NP 7S showed independent prognostic value (adjusted hazard ratio: 1.12, P=0.02), while ELF score did not (adjusted hazard ratio: 1.04, P=0.79). Conclusion Parallel elevation of P4NP 7S and ELF score were documented during acute phase of HF. P4NP 7S at discharge may identify patients at high risk for subsequent HF related events.

P6359Utility of collagen-derived peptides as markers of organ injury in patients with acute heart failure: a prospective cohort study

Abstract Background Organ injury in heart failure (HF) might evoke profibrotic response, which might adversely affect prognosis.In patients with HF, liver fibrogenesis marker, type IV collagen 7S (P4NP 7S), correlates with pulmonary artery pressure and right-side cardiac pressure such as right atrial and ventricular pressure. The present study aimed to investigate the prognostic utility of two collagen markers (N-terminal propeptide of procollagen III [PIIINP] and P4NP 7S) in patients with acute HF. Methods and results We conducted a prospective cohort study including 390 patients admitted for HF to three territorial hospitals. The pre-specified primary outcome measure was cardiac death and HF hospitalization at early (90-day) and late (365-day) post-discharge period. Follow-up ratio was 99% at 90 day and 97% at 365 day, respectively. Cardiac death and HF hospitalization occurred in 61 and 114 patients at 90 days and 365 days, respectively. The dichotomization the patients based on the median value of the collagen marker at discharge revealed that patients with high P4NP 7S correlated with significant excess risk relative to those with low P4NP 7S for 90-day (adjusted hazard ratio [HR]; 1.89, 95% confidence interval [CI]); 1.11–3.26, P=0.02) and 365-day (adjusted HR; 1.50, 95% CI; 1.02–2.21, P=0.04) outcome. 10% increase in P4NP 7S was associated with 8% increase for primary outcome measure at 90 day (P=0.04). P4NP 7S showed incremental prognostic value on top of the conventional prognostic factors including age, sex, estimated glomerular filtration rate (eGFR), ejection fraction (EF) &lt;40%, B-type natriuretic peptide (BNP), hemoglobin and sodium &lt;140mmol/L (P=0.038 for net reclassification improvement, P=0.0068 for integrated discrimination improvement). PIIINP weakly correlated with P4NP 7S (Spearman's r=0.24, P&lt;0.0001), but it neither correrated with the marked excess risk not associated with significant excess risk for 90 and 365-day primary outcome measure nor enhanced the discrimination. Conclusions This study suggests a possible role of P4NP 7S in the risk stratification of patients with acute HF. Acknowledgement/Funding None

Circulating markers of collagen types I, III, and IV in patients with dilated cardiomyopathy: relationships with myocardial collagen expression.

AimsCollagen‐derived peptides such as collagen I C‐terminal telopeptide (CITP) and procollagen III N‐terminal propeptide (PIIINP) have been conventionally used as markers of cardiac fibrosis. Collagen IV 7S domain (P4NP 7S) has been recently reported to be correlated with haemodynamics in patients with acute heart failure. We investigated whether these markers reflect cardiac remodelling and myocardial collagen expression.Methods and resultsIn 80 patients with dilated cardiomyopathy, relationships of CITP, PIIINP, and P4NP 7S to clinical and echocardiographic variables were analysed. CITP and PIIINP were inversely correlated with estimated glomerular filtration rate (r = −0.41, P < 0.001 and r = −0.32, P = 0.004, respectively); P4NP 7S was positively correlated with B‐type natriuretic peptide (r = 0.32, P = 0.003) and γ‐glutamyltransferase (r = 0.38, P < 0.001). These correlations were significant even after adjustment by potential confounders, whereas all three collagen markers were not independently correlated with ejection fraction nor with left ventricular (LV) diastolic diameter. In 33 patients undergoing endomyocardial biopsy, myocardial collagen I and III mRNA expressions were correlated with LV end‐diastolic volume index (r = 0.42, P = 0.02 and r = 0.54, P = 0.002, respectively), whereas myocardial collagen IV mRNA expression was not correlated with LV end‐diastolic volume index nor with ejection fraction. Each collagen‐derived peptide was not significantly correlated with the myocardial expression of their corresponding collagen mRNA.ConclusionsOur study shows that CITP, PIIINP, and P4NP 7S do not reflect myocardial collagen mRNA expression but presumably reflect extra‐cardiac organ injury in heart failure.

Liver fibrosis marker, 7S domain of collagen type IV, in patients with pre-capillary pulmonary hypertension

BackgroundPulmonary hypertension (PH) causes right ventricular dysfunction and central venous congestion, and may lead to congestive hepatopathy. The serum 7S domain of collagen type IV (P4NP 7S) is an established marker of liver fibrosis in chronic liver disease. We aimed to determine whether P4NP 7S is related to hemodynamic parameters, and assessed the potential values of P4NP 7S to predict mortality. MethodsConsecutive 76 pre-capillary PH patients were divided into tertiles based on their serum P4NP 7S levels. We compared right-heart catheterization, echocardiographic findings, and mortality among the tertiles, and compared P4NP 7S with other known biomarkers of mortality. ResultsCardiac index, mean pulmonary arterial pressure, pulmonary vascular resistance, and right ventricular fractional area change did not differ among the three groups. In contrast, compared to 1st and 2nd tertiles, the 3rd tertile had higher levels of right atrial pressure, right atrial area, and right ventricular area (P<0.05, respectively). In the Kaplan-Meier analysis, mortality progressively increased from the 1st to 2nd and 3rd tertiles (log-rank, P=0.002). In the Cox proportional hazard analysis, P4NP 7S was a predictor of mortality. ROC analysis demonstrated that a P4NP 7S concentration of 4.75ng/ml predicted mortality (AUC 0.85, 95% CI 0.75–0.94; P<0.001), and that the prognostic value of P4NP 7S was comparable or superior to that of other biomarkers (total bilirubin, creatinine, uric acid, C-reactive protein, B-type natriuretic peptide, and troponin I). ConclusionsSerum P4NP 7S is associated with higher central venous pressure, right-sided volume overload, and mortality in PH patients.

Liver fibrogenesis marker, 7S domain of collagen type IV in patients with acutely decompensated heart failure: Correlates, prognostic value and time course

BackgroundCongestion in heart failure (HF) induces multiple organ injury, which may cause remodeling of extracellular matrix. We hypothesized that liver fibrogenesis marker, 7S domain of collagen type IV (P4NP 7S) was correlated with congestion and liver injury in HF. Methods and resultsWe measured serum P4NP 7S in two cohorts. Cohort 1 included 70 patients undergoing catheterization. P4NP 7S was correlated with pulmonary capillary wedge pressure, right ventricular and atrial pressure (r=0.50, P<0.001, r=0.42, P<0.001, r=0.39, P=0.001, respectively) but not with cardiac index (r=−0.05. P=0.7). Cohort 2 included 145 patients with acute HF, in whom we serially measured P4NP 7S at admission, discharge, early (1-month) and late (6-month) post-discharge period. γ-Glutamyltransferase and B-type natriuretic peptide were independently correlated with P4NP 7S at discharge. The cumulative 1-year incidence of death or HF hospitalization was much higher in the 3rd tertile of P4NP 7S than in the 1st and 2nd tertiles (50%, 25%, and 24%, Log-rank P=0.004). P4NP 7S enhanced risk classification when added to conventional risk factors (net reclassification improvement=0.47, P=0.02). In patients without early readmission, P4NP 7S decreased during hospitalization and remained low for up to 6months, whereas in patients with early readmission, P4NP 7S was persistently elevated during hospitalization, further increased at second admission, and remained high at 6months. ConclusionP4NP 7S was correlated with hemodynamics. The results shed new light on the pathophysiology of HF.

Characterization of serological neo-epitope biomarkers reflecting collagen remodeling in clinically stable chronic obstructive pulmonary disease

ObjectivesChronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation that leads to excessive remodeling of the lung extracellular matrix (ECM), resulting in release of protein fragments (neo-epitopes) to the blood. Serological markers assessing this have previously been associated with exacerbations of COPD. However, characterization of these in individuals with clinically stable COPD is lacking. The aim of this study was to characterize the collagen remodeling in stable COPD by the serological assessment of neo-epitopes. Design and methodsSixty-eight subjects with clinically stable COPD were included into the study at baseline, and 27 came back for a four weeks follow-up visit. Serum and plasma levels of neo-epitopes were assessed for the evaluation of collagen type III (C3M), IV (C4M, C4Ma3, P4NP 7S), and VI (C6M, Pro-C6) remodeling. ResultsC3M, C4M, C4Ma3, P4NP 7S, and C6M levels were significantly elevated in COPD subjects compared with healthy controls (p<0.0001 to p=0.044). Each neo-epitope biomarker was significantly correlated between serum and plasma (p<0.0001) and most biomarkers were stable in the majority of patients from baseline to week four. Serum C6M levels were weakly correlated with FEV1% predicted (r=−0.274, p=0.025) and serum Pro-C6 levels were elevated in subjects with previous exacerbations (p=0.014). C3M, C4Ma3, C6M, and P4NP 7S were weakly correlated with MRC dyspnea scores (p<0.01). No associations were seen with BMI, smoking, duration of COPD, blood oxygen saturation, shuttle walk test distance, GOLD grades, or CAT scores. ConclusionsSerological biomarkers of collagen remodeling were elevated in subjects with COPD as compared with healthy individuals. Biomarker levels were significantly correlated with measures of dyspnea, indicating a relationship with degree of symptoms, while only C6M showed a weak but significant association with lung function. Biomarker levels were not related to GOLD grades, which was in line with previous studies indicating that ECM remodeling may be related to disease activity rather than severity.

Risk factors for incisional hernia after hepatic resection for hepatocellular carcinoma in patients with liver cirrhosis

The risk factors for incisional hernia (IH) and the association between liver fibrosis and IH after hepatic resection in patients with hepatocellular carcinoma (HCC) with liver cirrhosis (LC) are still unclear. We aimed to evaluate the rate of IH and to assess the effect of perioperative factors, including serum markers for liver fibrosis, on the risk of IH. A total of 192 patients with HCC with LC who received hepatectomy were retrospectively analyzed. The primary end point was the incidence rate of IH and the secondary end points were associations between IH and 22 clinical factors. IH was diagnosed in 60 (31.3%) patients. The estimated incidence rates were 19.8% at 12 months, 32.5% at 36 months, and 38.8% at 60 months. In multivariable analysis, the presence of postoperative intractable ascites (odds ratio 24.83, P = .0003), abdominal wall closure by a single-layer mass closure with a continuous running suture (odds ratio 4.59, P = .0143), preoperative body mass index ≥ 25 kg/m(2) (odds ratio 3.36, P = .0025), and preoperative serum N-terminal pro-peptide of type IV collagen 7S domain (P4NP 7S) levels ≥ 5 ng/mL (odds ratio 3.13, P = .0234) were independent risk factors. There are several risk factors for IH after hepatic resection in HCC patients with LC. Preoperative serum P4NP 7S levels ≥ 5 ng/mL are a useful predictive marker, and abdominal wall closure with a continuous running suture by a single-layer mass closure should be avoided.

Accelerated extracellular matrix turnover during exacerbations of COPD.

BackgroundExacerbations of chronic obstructive pulmonary disease (COPD) contribute significantly to disease progression. However, the effect on tissue structure and turnover is not well described. There is an urgent clinical need for biomarkers of disease activity associated with disease progression. Extracellular matrix (ECM) turnover reflects activity in tissues and consequently assessment of ECM turnover may serve as biomarkers of disease activity. We hypothesized that the turnover of lung ECM proteins were altered during exacerbations of COPD.Methods69 patients with COPD hospitalised for an exacerbation were recruited at admission and returned for a 4 weeks follow-up. Competitive ELISAs measuring circulating protein fragments in serum or plasma assessed the formation and degradation of collagen types III (Pro-C3 and C3M, respectively), IV (P4NP 7S and C4M, respectively), and VI (Pro-C6 and C6M, respectively), and degradation of elastin (ELM7 and EL-NE) and versican (VCANM).ResultsCirculating levels of C3M, C4M, C6M, ELM7, and EL-NE were elevated during an exacerbation of COPD as compared to follow-up (all P <0.0001), while VCANM levels were decreased (P <0.0001). Pro-C6 levels were decreased and P4NP 7S levels were elevated during exacerbation (P <0.0001). Pro-C3 levels were unchanged. At time of exacerbation, degradation/formation ratios were increased for collagen types III and VI and decreased for collagen type IV.ConclusionsExacerbations of COPD resulted in elevated levels of circulating fragments of structural proteins, which may serve as markers of disease activity. This suggests that patients with COPD have accelerated ECM turnover during exacerbations which may be related to disease progression.

Combined antiretroviral therapy attenuates hepatic extracellular matrix remodeling in HIV patients assessed by novel protein fingerprint markers.

Combined antiretroviral therapy (cART) attenuates hepatic fibrosis in hepatitis C virus and HIV coinfected patients. However, the role of HIV or cART on hepatic fibrosis in HIV monoinfection is discussed controversially. During liver fibrosis, matrix metalloproteinases (MMPs) degrade extracellular matrix (ECM) proteins into small soluble fragments, which reflect hepatic remodeling processes. This study used these novel biomarkers to investigate the effect of HIV and cART on hepatic fibrosis remodeling. In 249 patients with HIV monoinfection and 55 healthy controls, the serum levels of MMP-degraded collagen type III (C3M), biglycan (BGM), elastin (ELM), as well as the formation marker 7S (P4NP 7S), and MMP-degraded collagen type IV (C4M) were determined using specific ELISAs. Sixty-eight patients underwent a follow-up visit 3 years later including assessment of ECM markers and fibrosis using transient elastography (Fibroscan). C3M, BGM, C4M and P4NP 7S were significantly elevated in HIV patients compared to controls and correlated to HIV viral loads and inversely to cART duration. C4M, P4NP 7S and ELM were lower in patients under cART therapy and in patients without HIV viremia, indicating that lowering of the HIV load by cART attenuates remodeling of ECM. The levels of C3M, C4M, P4NP 7S and ELM correlated significantly with the progression of fibrosis in these patients. Specific therapy of patients with HIV monoinfection also beneficially influences liver fibrosis. These novel markers of liver fibrosis remodeling may help to monitor the hepatic effects by HIV therapy.

Novel serological neo-epitope markers of extracellular matrix proteins for the detection of portal hypertension

SummaryBackgroundThe hepatic venous pressure gradient (HVPG) is an invasive, but important diagnostic and prognostic marker in cirrhosis with portal hypertension (PHT). During cirrhosis, remodelling of fibrotic tissue by matrix metalloproteinases (MMPs) is a permanent process generating small fragments of degraded extracellular matrix (ECM) proteins known as neoepitopes, which are then released into the circulation.AimTo investigate their potential as plasma markers for detection of PHT.MethodsNinety-four patients with alcoholic cirrhosis and 20 liver-healthy controls were included. Clinical and laboratory data of the patients were collected. All patients received HVPG measurement with blood sampling. In these samples, the following degradation or formation markers were measured: C1M (type I-collagen), C3M and PRO-C3 (type III collagen), C4M and P4NP 7S (type IV collagen), C5M (type V collagen), C6M (type VI collagen), BGM (biglycan), ELM (elastin), CRPM (CRP).ResultsAll ECM markers except for CRPM correlated significantly with HVPG. Interestingly, C4M, C5M and ELM levels were significantly higher in patients with HVPG >10 mmHg. Multiple regression analysis identified PRO-C3, C6M and ELM as significant determinants, while the models A and B including PRO-C3, ELM, C6M and model for end-stage liver disease (MELD) provided better description of PHT (r = 0.75, P < 0.0001). The models provided odds ratios of >100 for having clinical significant PHT.ConclusionsThese novel non-invasive extracellular matrix markers reflect the degree of liver dysfunction. The different degrees of portal hypertension correlated with these circulating neoepitopes. Using a single blood sample, these neoepitopes in combination with MELD detect the level of portal hypertension.

Protein fingerprinting of the extracellular matrix remodelling in a rat model of liver fibrosis—a serological evaluation

We investigated nine novel biomarkers of extracellular matrix (ECM) remodelling in a rat model of liver fibrosis. Liver fibrosis was induced in 52 male Wistar rats by inhalation of carbon tetrachloride and the level of hepatic fibrosis was assessed by Sirius red staining compared with controls. The novel serum biochemical markers assessed in the model were type I-(C1M), type III-(C3M), type IV-(C4M) and type VI-(C6M) collagen, citrullinated vimentin (VICM) and biglycan (BGM) all protein fragments generated by matrix metalloproteinases; and formation markers of type III-(P3NP), type VI (P4NP 7S) and type V (P5CP) collagen; hepatic mRNA type I collagen alpha-1 chain levels, serum potassium, sodium, osmolarity, alanine aminotransferase, lactate dehydrogenase, albumin and creatinine. Stratification of the CCl(4) -treated rats according to total hepatic collagen showed that the degradation markers were significantly elevated in mild to severe fibrosis except for C6M which was also elevated in early fibrosis (P < 0.05). The highest Z-scores in early and moderate fibrosis were provided by P4NP 7S and alanine aminotransferase. All nine markers of ECM remodelling were highly related to the extent of liver fibrosis induced by CCl(4) . The novel collagen formation marker, P4NP 7S, was reliable for the detection of early fibrosis, while the combination of the two markers, C6M and P5CP provided the best correlation with hepatic fibrosis in all fibrosis levels. As the markers can be used for translational science, these markers may provide valuable information for the evaluation of liver fibrosis in clinical settings.

Enzyme‐linked immunosorbent serum assay specific for the 7S domain of Collagen Type IV (P4NP 7S): A marker related to the extracellular matrix remodeling during liver fibrogenesis

The present study describes the ability of a newly developed N-terminal pro-peptides of type IV collagen 7S domain (P4NP 7S) competitive enzyme-linked immunosorbent assay (ELISA) for describing liver fibrosis. The assay applies a monoclonal antibody specific for a PIVNP 7S epitope 100% homologous in the human, rat, and mouse species. Monoclonal antibodies were raised against selected P4NP 7S specific sequences. Antibodies were screened and a competitive ELISA assay was developed using a selected antibody. The assay was evaluated in relation to technical performance, and in two preclinical liver fibrosis models; the bile duct ligation model (BDL) and the carbon tetrachloride model (CCL4) both performed in rats. A technically robust P4NP 7S ELISA assay using a monoclonal antibody was produced. In the BDL and CCL4 liver fibrosis models it was observed that the P4NP 7S levels were significantly elevated in rat with liver fibrosis as seen by histology (CCL4: 283% elevated in the highest quartile of total hepatic collagen compared with controls, P = 0.001; BDL: 183% elevated at week 4 compared with sham, P < 0.001) and correlated to the amount of hepatic type IV collagen expression in BDL rats (r = 0.49, P < 0.05) in contrast to sham (r = -0.12). P4NP 7S also correlated to total collagen in CCL4 treated livers (P < 0.001, r = 0.67), however, not in controls (r = 0.04). This newly developed serum assay specific for P4NP 7S was highly related to liver fibrosis and correlated to extent of hepatic fibrosis. This assay may improve fibrosis quantification.