Clinical significance of serum 7S collagen in various liver diseases

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.

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

Objective

This 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 patients with acute heart failure (HF).

Methods

390 patients with acute HF were dichotomised based on the median value of fibrosis markers at discharge. The primary outcome measure was a composite of cardiac death and HF hospitalisation.

Results

P4NP 7S significantly declined during hospitalisation, whereas PIIINP did not. The cumulative 90-day and 365-day incidence of the primary outcome measure was 16.6% vs 16.0% (p=0.42) and 33.3% vs 28.4% (p=0.34) in the patients with high versus low PIIINP; 19.9% vs 13.0% (p=0.04) and 32.3% vs 29.0% (p=0.34) in the patients with high and low P4NP 7S, respectively. After adjusting for confounders, high P4NP 7S correlated with significant excess risk relative to low P4NP 7S for both 90-day and 365-day primary outcome measure (adjusted HR, 1.50; 95% CI, 1.02 to 2.21; p=0.04 and adjusted HR, 1.89; 95% CI, 1.11 to 3.26; p=0.02, respectively), which was driven by significant association of high P4NP 7S with higher incidence of HF hospitalisation. Furthermore, P4NP 7S exhibited an additive value to conventional prognostic factors for predicting 90-day outcome (p=0.038 for net reclassification improvement; p=0.0068 for integrated discrimination improvement). High PIIINP did not correlate with significant excess risk for both 90-day and 365-day outcome.

Conclusions

This study suggests a possible role of P4NP 7S in the risk stratification of patients with acute HF.

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

Aims

Collagen‐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 results

In 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.

Conclusions

Our 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.

Correlation between the serum levels of type IV collagen 7s domain and the risk of intractable ascites following liver resection for hepatocellular carcinoma: A propensity score-matched analysis

BACKGROUND

The severity of liver fibrosis has been reported to be correlated with the risk of intractable ascites after hepatectomy for hepatocellular carcinoma. Since 2009, we have measured routinely the serum concentrations of type IV collagen 7s domain (7s collagen), a biochemical marker of liver fibrosis and applied limited resection to patients with elevation of the serum 7s collagen concentrations above the upper limit of normal (6.0 ng/mL). The aim of this study was to assess the potential benefits of our treatment strategy on the postoperative outcomes of patients with hepatocellular carcinoma.

METHODS

A propensity score-matched analysis was performed to compare the outcomes between patients who underwent initial hepatectomy for hepatocellular carcinoma before or after 2009 (2009 to April 2015; period 2) and those who underwent the operation prior to 2009 (1990-2008; period 1; n = 129 in each period).

RESULTS

The incidence of intractable ascites was significantly lower in period 2 than in period 1 (2.3 vs 14.7%; P < .001), although the other short-term and long-term outcomes were comparable between the 2 groups. A multivariate analysis identified elevation of the serum 7s collagen concentrations to ≥7.4 ng/mL as an independent predictor of IA (odds ratio 14.1, 95% confidence interval 2.8 to 106.7; P = .001), with the area under the receiver-operating characteristic curve of 0.820 (0.648-0.919, P = .005).

CONCLUSION

Modification of the surgical procedure according to the serum 7s collagen concentration is beneficial for reducing the risk of development of intractable ascites after hepatectomy for hepatocellular carcinoma.

Evaluation of Fucosylated Haptoglobin and Mac-2 Binding Protein as Serum Biomarkers to Estimate Liver Fibrosis in Patients with Chronic Hepatitis C

Fucosylated haptoglobin (Fuc-Hpt) and Mac-2 binding protein (Mac-2 bp) are identified as cancer biomarkers, based on the results from a glyco-proteomic analysis. Recently, we reported that these glyco-biomarkers were associated with liver fibrosis and/or ballooning hepatocytes in patients with nonalcoholic fatty liver disease (NAFLD). We evaluated the ability of these glycoproteins to estimate liver fibrosis in 317 patients with chronic hepatitis C. We measured the serum Fuc-Hpt and Mac-2 bp levels using a lectin-antibody ELISA and ELISA, respectively. The serum levels of both Fuc-Hpt and Mac-2 bp increased with the progression of liver fibrosis. The multivariate analysis revealed that Mac-2 bp was an independent factor associated with moderate liver fibrosis (F ≥ 2). In contrast, Fuc-Hpt was an independent factor associated with advanced liver fibrosis (F ≥ 3). In terms of evaluating liver fibrosis, the serum levels of these glycomarkers were correlated with well-known liver fibrosis indexes, such as the aspartate aminotransferase to platelet ratio index (APRI) and Fibrosis-4 (FIB4) index. An assay that combined the APRI or FIB4 index and the Fuc-Hpt or Mac-2 bp levels increased the AUC value for diagnosing hepatic fibrosis. Interestingly, the cumulative incidence of hepatocellular carcinoma (HCC) was significantly higher in the patients with elevated serum levels of Fuc-Hpt and Mac-2 bp. In conclusion, both Fuc-Hpt and Mac-2 bp could be useful glyco-biomarkers of liver fibrosis and predictors of HCC in patients with chronic hepatitis C.

Impact of serum glycosylated Wisteria floribunda agglutinin positive Mac-2 binding protein levels on liver functional reserves and mortality in patients with liver cirrhosis

AIM

Serum glycosylated Wisteria floribunda agglutinin positive Mac-2 binding protein (WFA(+) -M2BP) levels are a non-invasive and reliable marker to assess the degree of liver fibrosis. We investigated the use of WFA(+) -M2BP levels to predict mortality in patients with liver cirrhosis (LC).

METHODS

This retrospective study consisted of 59 consecutive patients. Liver fibrosis was estimated by hyaluronic acid (HA), 7S fragment of type IV collagen (7S collagen), aspartate aminotransferase-to-platelet ratio index (APRI) and FIB-4 index. The severity of liver disease was evaluated by Child-Pugh classification and the Model for End-Stage Liver Disease (MELD) score. Cox proportional hazards regression analysis was performed to evaluate risk factors for mortality, and the diagnostic accuracy of WFA(+) -M2BP levels to predict mortality was examined using receiver-operator curves.

RESULTS

Serum WFA(+) -M2BP levels of Child-Pugh class A, B and C had cut-off indexes (COI) of 2.90, 6.15 and 9.45, respectively. WFA(+) -M2BP levels were positively correlated with HA, 7S collagen, APRI, FIB-4 index, Child-Pugh class and MELD score. Multivariate analysis identified WFA(+) -M2BP levels as an independent risk factor of mortality (hazard ratio = 1.19, 95% confidence interval = 1.02-1.41, P = 0.03), and the optimal cutoff point to predict mortality was 5.0 COI. The survival rate was significantly lower in patients with WFA(+) -M2BP levels 5.0 or more COI than in patients with WFA(+) -M2BP of less than 5.0 COI (P = 0.002).

CONCLUSION

Serum WFA(+) -M2BP levels were significantly correlated with both liver function reserves and liver fibrosis, and were independently associated with mortality in patients with LC.

Serum surrogate markers of liver fibrosis in primary biliary cirrhosis

BACKGROUND

Hyaluronan, leptin, laminin and collagen IV have been used extensively for the assessment of liver fibrosis. The aim of this study was to assay these markers in the peripheral and hepatic vein blood of primary biliary cirrhosis (PBC) patients and to study their ability to discriminate early from advanced disease.

METHODS

Sera from 62 PBC patients were compared to 60 controls, 44 chronic Hepatitis C, 38 hepatocellular carcinoma and 34 viral cirrhosis patients. Serum from the hepatic vein of 15 cirrhotic PBC patients and 17 patients with viral cirrhosis was also assayed.

RESULTS

All disease groups had significantly increased levels of hyaluronan and collagen IV, compared to controls, while laminin was significantly increased only in viral cirrhosis. Hyaluronan levels were statistically different between early (54.5 ng/ml; 95%CI 27.3-426.9) and late PBC (154.5 ng/ml; 95%CI 55.3-764.4, p<0.05). The area under the curve (AUC) for the identification of late PBC was 0.74 for hyaluronan, 0.63 for leptin, 0.59 for laminin and 0.70 for collagen IV. Hyaluronan had high sensitivity and NPV in identifying late stages of PBC (96% and 90%, respectively). Short term UDCA had no effect on these markers.

CONCLUSION

No single measurement can differentiate between advanced and early fibrosis in PBC. However serum hyaluronan is a promising single serum marker for longitudinal studies in PBC.

Type IV collagen levels are elevated in the serum of patients with peritoneal dissemination of gastric cancer

Type III procollagen (amino-terminal propeptide of procollagen type III) and type IV collagen are considered to be reliable serum markers for monitoring the progression of liver fibrosis. The peritoneal dissemination of gastric cancer is also characterised by abundant collagen deposition in the peritoneum. The present study was performed to investigate the potential of serum type III procollagen and IV collagen as biomarkers for peritoneal dissemination in gastric cancer. The study population consisted of 117 patients with gastric cancer: 32 patients had peritoneal dissemination which was pathologically diagnosed by laparotomy or laparoscopic examination, while 85 patients (45/40, early/advanced gastric cancer) had no peritoneal dissemination. We measured the serum levels of type III procollagen and type IV collagen in comparison to the commonly accepted tumor markers carcinoembryonic (CEA), carbohydrate antigen (CA)19-9 and CA125. The median type III procollagen levels showed no significant differences between the two groups, whereas the median type IV collagen levels were significantly (201 ng/ml) higher in patients with than in those without peritoneal dissemination (early/advanced gastric cancer, 124/136 ng/ml) (P<0.05). In receiver operating characteristic (ROC) curve analysis, type IV collagen had the largest area under the curve (0.83), followed by CA125 (0.72), CA19-9 (0.64), CEA (0.59) and type III procollagen (0.48). Type IV collagen was an independent marker (P<0.0001, odds ratio 15.7) for predicting peritoneal dissemination along with CA125 (P=0.0086, odds ratio 9.4) based on multivariate logistic regression. In conclusion, serum type IV collagen levels may be significant in the early detection and management of patients with peritoneal dissemination of gastric cancer.

Periostin and bone marrow fibrosis

Periostin is a secreted protein that shares structural homology with the insect axon guidance protein fasciclin 1. Periostin is expressed predominantly in collagen-rich fibrous connective tissues that are subjected to constant mechanical stresses. We have shown previously that periostin is a novel component of subepithelial fibrosis in bronchial asthma. Here, we investigated the relationship between periostin and bone marrow (BM) fibrosis. Periostin was expressed in the stroma and stromal cells of BM fibrosis specimens and to a great extent its expression levels correlated closely to the grade of fibrosis, as estimated by silver staining. However, in the present study, we found no relationship between plasma periostin levels and the extent of BM fibrosis. We also demonstrated that periostin is secreted by human BM hTERT stromal cells and that its secretion is enhanced by TGF-beta, a cytokine produced by clonal proliferation of megakaryocytes and/or monocytes. These results indicate that periostin is a component of BM fibrosis and that it may play a role in the disease progression.

Usefulness of noninvasive transient elastography for assessment of liver fibrosis stage in chronic hepatitis C

AIM: To evaluate the method of noninvasive transient elastography for assessment of histological stage of liver fibrosis in patients with chronic hepatitis C (CHC).

METHODS: Two hundred and thirty-seven patients with CHC were included in this study. Liver biopsy was performed under ultrasonography on 217 of the patients, excluding twenty with clear clinical evidence of liver cirrhosis. Fifty subjects without liver disease were enrolled as a control group (stage 0). Twenty-five patients with sustained virological response (SVR) to interferon (IFN) therapy were also enrolled. These patients underwent liver biopsy before IFN therapy. Examination of liver stiffness (LS) was performed by elastography.

RESULTS: Medians (50% levels) of LS were 4.1 (3.5-4.9), 6.3 (4.8-8.5), 8.8 (6.8-12.0), 14.6 (10.5-18.6), and 22.2 (15.4-28.0), respectively, in the fibrosis stages 0-4 (P < 0.001). LS was significantly correlated with four serum fibrosis markers. LS values in patients with SVR were 3.8 (3.5-5.6), 5.2 (4.4-6.8), 6.8 (6.1-7.6), and 6.1 (3.6-7.9), respectively, in the fibrosis stages 1-4. In all stages, LS for patients with SVR was significantly lower than that for patients who did not undergo IFN therapy. LS was significantly correlated with serum concentrations of hyaluronic acid, type IV collagen, type IV collagen 7S, and type III procollagen N peptide.

CONCLUSION: LS correlated well with the histological stage of fibrosis. Changes in liver fibrosis stage may thus be estimated noninvasively using transient elastography.

Diagnosis and monitoring of hepatic injury. II. Recommendations for use of laboratory tests in screening, diagnosis, and monitoring

Purpose: To review information on the use of laboratory tests in screening, diagnosis, and monitoring of acute and chronic hepatic injury.

Data Sources and Study Selection: A MEDLINE search was performed for key words related to hepatic diseases, including acute hepatitis, chronic hepatitis, alcoholic hepatitis, cirrhosis, hepatocellular carcinoma, and etiologic causes. Abstracts were reviewed, and articles discussing use of laboratory tests selected for review. Additional articles were selected from the references.

Guideline Preparation and Review: Drafts of the guidelines were posted on the Internet, presented at the AACC Annual Meeting in 1999, and reviewed by experts. Areas requiring further amplification or literature review were identified for further analysis. Specific recommendations were made based on analysis of published data and evaluated for strength of evidence and clinical impact.

Recommendations: Although many specific recommendations are made in the guidelines, only some summary recommendations are listed here. In acute hepatic injury, prothrombin time and, to a lesser extent, total bilirubin are the best indicators of severity of disease. Although ALT is useful for detecting acute and chronic hepatic injury, it is not related to severity of acute hepatic injury and only weakly related to severity of chronic hepatic injury. Specific tests of viral markers should be the initial differential tests in both acute and chronic hepatic injury; when positive, they are also useful for monitoring recovery from hepatitis B and C.

Prognostic value of serum procollagen III peptide and type IV collagen in patients with biliary atresia

BACKGROUND/PURPOSE

Progressive hepatic fibrosis, in spite of a successful Kasai procedure, is a major problem in patients with biliary atresia (BA). Early identification of patients at risk would be of great value. N-terminal procollagen-III peptide (PIIIP) (which is a marker of fibrogenesis and, therefore, of on going inflammation), and type IV collagen (found in basement membrane extracellular matrix), were measured in patients with BA to determine their potential as prognostic markers.

METHODS

Thirty-three postoperative BA patients (11.0+/-3.7 years old) and 20 normal controls (10.5+/-2.8 years old) were studied. The BA patients were classified on the basis of their current liver function test results into three outcome groups. Group I (n = 9) had severe liver dysfunction, group II (n = 13) had moderate, and group III (n = 11) had good liver function. Serum P-III-P and type IV collagen values were determined by radioimmunoassays and one step sandwich enzyme immunoassay.

RESULTS

In group I, serum PIIIP (1.93+/-0.64 U/mL) and type IV collagen levels (363.5+/-69.5 ng/mL) were significantly higher than in group II (PIIIP [1.32+/-0.25 U/mL], type IV collagen [225.3+/-45.4 ng/mL]; P < .01). There were increased levels in serum PIIIP and serum type IV collagen in group II compared with group III (PIIIP [1.01+/-0.25 U/mL], type IV collagen [171.3+/-47.2 ng/mL]; P < .01). There were no significant differences in serum PIIIP and type IV collagen levels between group III and controls.

CONCLUSION

The authors conclude that serum levels of PIIIP and type IV collagen may be useful in the long-term follow-up of BA patients after Kasai's portoenterostomy.

Serum levels of tissue inhibitor of metalloproteinases-2 and of precursor form of matrix metalloproteinase-2 in patients with liver disease

Serum levels of tissue inhibitor of metalloproteinases-2 (TIMP2) and of precursor form of matrix metalloproteinase-2 (proMMP2) were determined in patients with chronic hepatitis and hepatocellular carcinoma by a one-step sandwich enzyme immunoassay. Serum levels of TIMP2 and proMMP2 were significantly higher in patients with chronic liver disease, than in normal controls. Serum levels of TIMP2 showed a weak negative correlation with the serum albumin level and prothrombin time (PT). Serum levels of proMMP2 in patients with chronic hepatitis were strongly correlated with those of type IV collagen and were negatively correlated with PT and serum albumin levels. Serum proMMP2 levels were also significantly correlated with histological stages. These data indicate that serum levels of proMMP2 might be useful in the follow-up of patients with chronic hepatitis.

Noninvasive determination of liver collagen content in chronic hepatitis. Multivariate regression modeling with blood chemical parameters as variables

To evaluate the diagnostic utility of blood biochemical parameters in assessing degree of hepatic fibrosis, serum levels of aminoterminal type III procollagen peptide (P III P), type IV collagen (IV-collagen), 7S domain of type IV collagen (7S-collagen), and hyaluronan (HA) were measured in 54 patients with chronic viral liver disease. Liver collagen content was quantified by a computer-assisted image analysis method. Significant correlations were found between the amount of collagen in the liver and serum levels of P III P (r = 0.482; P < 0.02), IV-collagen (r = 0.705; P < 0.001), 7S-collagen (r = 0.771; P < 0.001), and HA (r = 0.595; P < 0.001). To optimize diagnostic efficacy, we applied multivariate regression analysis to the combined results obtained for these blood biochemical parameters and some additional laboratory tests. The correlation coefficient obtained from the application of this model was 0.809. To measure the predictive value of the proposed model, we used it to estimate collagen content in an additional 16 patients with chronic liver disease and compared the estimated to the actual amount of collagen determined by direct measurement. The correlation coefficient was 0.937. These results suggest that application of the model would be useful for the assessment of collagen content of fibrotic liver.

Plasma vitronectin concentrations in patients with chronic hepatitis C treated with interferon alpha

Plasma vitronectin concentration was measured in 60 patients with chronic hepatitis C before and after interferon alpha treatment. The plasma pretreatment levels of vitronectin in the interferon non-responders was significantly lower than those in the interferon sustained and transient responders, but the levels were not different in the latter two groups. After interferon therapy, the plasma levels of vitronectin were significantly increased in all three groups, and they were correlated with the albumin levels. Absolute changes of plasma vitronectin before and after interferon treatment were significantly related to initial levels, but they were not related to those of albumin or alanine aminotransferase levels. The values of sensitivity and specificity for plasma vitronectin in the sustained responder and non-responder were 45% and 95% for each. These results suggest that chronic hepatitis C patients with low levels of plasma vitronectin may have a weak response in interferon therapy.

Collagen-binding activity of plasma vitronectin in chronic liver disease

The collagen-binding activity of plasma vitronectin was measured in 15 control subjects and 64 subjects with chronic liver disease. The assay of collagen-binding vitronectin was performed by an enzyme immunoassay using a monoclonal antibody to human vitronectin and type I collagen from human placenta. The plasma collagen-binding vitronectin concentration (mean +/- S.D.) was 5.6 +/- 1.9 micrograms/ml in the controls, 8.3 +/- 1.1 micrograms/ml in chronic persistent hepatitis, 8.3 +/- 2.9 micrograms/ml in chronic active hepatitis, 7.8 +/- 2.9 micrograms/ml in liver cirrhosis and 8.2 +/- 2.1 micrograms/ml in hepatocellular carcinoma with cirrhosis. The percent collagen-binding vitronectin to total plasma vitronectin was 2.2 +/- 0.8% in the controls, 3.9 +/- 2.2% in chronic persistent hepatitis, 3.9 +/- 1.2% in chronic active hepatitis, 5.8 +/- 3.3% in liver cirrhosis and 4.1 +/- 1.2% in hepatocellular carcinoma with cirrhosis. The plasma collagen-binding vitronectin also correlated with the serum levels of 7S collagen and hyaluronic acid. These findings suggest that vitronectin may play an important role in the progression of liver disease and/or in hepatic fibrosis through its collagen-binding domain.

Serum markers for fibrosis and plasma transforming growth factor-beta 1 in patients with hepatocellular carcinoma in comparison with patients with liver cirrhosis

In order to elucidate collagen metabolism in hepatocellular carcinoma (HCC) tissue, we compared levels of different potential markers of collagen metabolism and plasma transforming growth factor-beta 1 in patients with HCC and in patients with liver cirrhosis. Serum levels of prolyl hydroxylase and the tissue inhibitor of metalloproteinase-1 in patients with HCC were significantly higher than those in patients with liver cirrhosis and increased with the size of the HCC tumour, whereas the serum levels of procollagen type III propeptide and type IV collagen 7S domain were similar in the two groups. In HCC, the increased plasma transforming growth factor-beta 1 levels were closely correlated with serum levels of prolyl hydroxylase and the tissue inhibitor of metalloproteinase-1. These findings suggest that, in HCC tissue, the intracellular biosynthesis of collagen is enhanced, whereas the secretion of procollagen is disturbed and the degradation of collagen is suppressed by the excess production of the tissue inhibitor of metalloproteinase-1. The results also suggest that plasma transforming growth factor-beta 1 plays an important role in the altered metabolism of collagen in HCC.

Comparison of serum 7S fragment of type IV collagen and serum central triple-helix of type IV collagen for assessment of liver fibrosis in patients with chronic viral liver disease

BACKGROUND/AIMS

A competitive radioimmunoassay for serum 7S fragment of type IV collagen (7S collagen) using a polyclonal antibody against 7S collagen and a sandwich enzyme immunoassay for serum central triple-helix of type IV collagen (IV collagen) using two monoclonal antibodies against the pepsin-solubilized type IV collagen may be used as diagnostic aids for liver fibrosis in clinical medicine. We compared the clinical usefulness for assessing liver fibrosis of serum 7S collagen and IV collagen tests in chronic viral liver diseases, and also examined the elution pattern of 7S collagen- and IV collagen-related antigens in serum by gel filtration analysis.

METHODS

Serum 7S collagen and IV collagen levels were assayed in 151 patients with chronic viral liver disease and 30 healthy control subjects.

RESULTS

Gel filtration on the Sephacryl S400HR column revealed that the 7S collagen antigenicity in serum was heterogeneous, whereas the IV collagen antigen in serum was uniform in size. Serum levels of 7S collagen and IV collagen showed increases closely correlated with the severity of liver disease. The abnormal percentage of 7S collagen in three patient groups was similar to that of IV collagen in the corresponding groups. Serum 7S collagen and IV collagen levels were strongly correlated with the histological degree of liver fibrosis; the correlation coefficients were r = +0.675 for 7S collagen and r = +0.665 for IV collagen. When we assessed the ability of each test to detect cirrhosis with a receiver operating curve, the serum 7S collagen test was a slightly better marker than the serum IV collagen test. For the detection of cirrhosis, serum 7S collagen was 83% sensitive and 88% specific at a cutoff value of 9 ng/ml, and serum IV collagen was 80% sensitive and 81% specific at a cutoff value of 160 ng/ml.

CONCLUSIONS

These findings suggested that serum 7S collagen and IV collagen tests are similarly useful for assessing liver fibrosis in patients with chronic viral liver disease, although the former is slightly better for diagnosing cirrhosis than the latter.

Serum markers for connective tissue turnover in patients with chronic hepatitis B and chronic hepatitis C: a comparative analysis

BACKGROUND/AIMS

Clinical and pathological differences between chronic hepatitis B and chronic hepatitis C have now been established.

METHODS

To compare hepatic connective tissue metabolism in chronic hepatitis B and C, we determined serum levels of prolyl 4-hydroxylase beta-subunit, procollagen III aminoterminal peptide, type IV collagen 7S domain, the central helix region of type IV collagen, tissue inhibitor of metalloproteinase, and hyaluronan in 55 patients with chronic hepatitis B and 83 patients with chronic hepatitis C.

RESULTS

There were no significant differences in the above markers for connective tissue turnover between the chronic hepatitis B group and the chronic hepatitis C group.

CONCLUSIONS

These results suggest that the accelerated connective tissue metabolism observed in chronic viral hepatitis is independent of the causative virus.

Distribution of vitronectin in plasma and liver tissue: relationship to chronic liver disease

To clarify the clinical significance of vitronectin, we compared the concentration of plasma vitronectin with serum fibrous markers and liver function test values in patients with chronic liver diseases. We also evaluated the vitronectin content in the liver by means of enzyme-linked immunosorbent assay and the localization of vitronectin in liver tissue with enzyme immunohistochemistry. In chronic liver disease, the concentration of plasma vitronectin was significantly lower than that in healthy controls, being related to the severity of liver disease. The plasma levels of vitronectin showed no correlation to fibrous markers but a significant correlation with those of serum albumin and prothrombin time. On the other hand, the content of vitronectin in liver tissue was significantly increased in chronic liver disease compared with that in normal controls. In the normal liver, vitronectin was observed in the portal area by light microscopy. In chronic hepatitis and cirrhosis, vitronectin was found in the connective tissue around the portal and central veins and in the areas of piecemeal and focal necrosis. These findings suggested that vitronectin is deposited in injured tissue through the process of repair and fibrosis and plays an important role as an adhesive protein. Moreover, the lower levels of plasma vitronectin in chronic liver disease may be due to its decreased synthesis, deposition or both in injured tissue.

Serum type III procollagen peptide, type IV collagen 7S domain, central triple-helix of type IV collagen and tissue inhibitor of metalloproteinases in patients with chronic viral liver disease: relationship to liver histology

To assess the clinical value of serum biochemical markers, the aminoterminal peptide of type III procollagen, type IV collagen 7S domain, the central triple-helix of type IV collagen and tissue inhibitor of metalloproteinases, as a marker of hepatic fibrosis, we measured these four serum markers in 132 patients with chronic viral liver disease and compared these serum markers with liver histological findings. Serum levels of these markers increased closely with the progress of liver disease, and the abnormal percentages of type III procollagen peptide, type IV collagen 7S domain, central triple-helix of type IV collagen and tissue inhibitor of metalloproteinases in patients with cirrhosis were 97%, 95%, 83% and 48%, respectively. These four serum markers strongly correlated with the histological degree of periportal with or without bridging hepatocellular necrosis and of liver fibrosis and correlated weakly with the degree of intralobular degeneration and focal necrosis and the degree of portal inflammation. The correlation coefficients of serum type IV collagen 7S domain with periportal with or without bridging hepatocellular necrosis and with liver fibrosis were the highest among these four serum markers, suggesting that serum type IV collagen 7S domain is the most valuable diagnostic marker to assess the degree of liver fibrosis in chronic viral liver disease. When we assessed the ability of each serum marker to detect cirrhosis with a receiver operating curve, the best test was type IV collagen 7S domain, and the second best was type III procollagen peptide.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes of serum 7S fragment of type IV collagen and N-terminal propeptide of type III procollagen after transcatheter arterial embolization as a model of acute liver injury

To evaluate the mechanism of increased serum concentrations of the N-terminal propeptide of type III procollagen and the 7S fragment of type IV collagen in acute liver injury, we serially measured serum levels of these substances after transcatheter arterial embolization in patients with hepatocellular carcinoma. The results demonstrated marked increases in serum levels of the 7S fragment of type IV collagen in accordance with increased serum levels of transaminase after transcatheter arterial embolization. In contrast, a transient decrease in serum levels of the N-terminal propeptide of type III procollagen was found after transcatheter arterial embolization and transcatheter arterial infusion, although no significant changes in serum levels of the N-terminal propeptide and 7S fragment were seen after hepatic arteriography alone. The absolute change in serum levels of the 7S fragment after treatment showed positive correlation with serum transaminase levels and negative correlation with the decrease in serum levels of alpha-fetoprotein, although serum levels of N-terminal peptide did not demonstrate such a correlation. The results suggest that in acute liver injury induced by transcatheter arterial embolization, at least in part, increased in serum levels of the 7S fragment of type IV collagen reflect accelerated liberation of type IV collagen from the destroyed surrounding nontumorous tissues and that decreased serum N-terminal propeptide of type III procollagen reflects diminished synthesis of type III collagen caused by anticancer drugs.