Serum enzymes of collagen synthesis and type III procollagen amino-propeptide in Nigerian patients with sickle cell disease

Serum immunoreactive prolyl hydroxylase protein, galactosylhydroxylysyl glucosyltransferase activity and the aminoterminal propeptide of type III procollagen were measured in 20 patients with sickle cell disease and the values were compared with those in 20 apparently healthy Nigerians. The means for the two enzymes and serum aminoterminal propeptide of type III procollagen were significantly higher in the sickle cell disease patients. Significant correlations were found between the values for the two enzymes and the protein serum aminoterminal propeptide of type III procollagen within the sickle cell disease patients. The data confirm that collagen formation is found in the liver, bone and other organs of patients with this disease. The measurement of serum immunoreactive prolyl hydroxylase protein, serum galactosylhydroxylysyl glucosyltransferase activity and serum aminoterminal propeptide of type III procollagen in prospective studies might be helpful in predicting hepatic, bone or diffuse fibrogenesis in sickle cell disease.     

Collagen peptidase and type III procollagen peptide serum levels in chronic liver diseases.

The concentration of the N-terminal peptide of procollagen III and the activity of collagen peptidase (PZ-peptidase) were measured in sera from 92 patients with chronic liver disease. In patients with liver cirrhosis and chronic hepatitis with transformation of liver structure, high values were found for both variables compared with hepatoses and chronic hepatitis without transformation. The concentration of procollagen III peptide and the activity of collagen peptidase in serum increased with increasing degrees of fibrosis and, even more markedly, with increasing degrees of mesenchymal activity in the liver.     

Serum procollagen type III peptide in chronic hepatitis B

The clinical significance of serum procollagen type III peptide, a marker of active fibrogenesis, was evaluated in 110 hepatitis B surface antigen positive patients with chronic hepatitis (32 chronic persistent hepatitis, 60 chronic active hepatitis, and 18 active cirrhosis), selected on the basis of active viral replication and biochemical activity, including 54 cases treated with interferon-α. At presentation the procollagen type III peptide level serum was above normal in 48 (44%) of the 110 patients and the median value was significantly higher than that of healthy carriers with normal transaminases and histology (P<0.000005). Semiquantitative histological evaluation showed a significant correlation between serum procollagen type III peptide levels and necrosis/inflammation in the subgroup of patients with chronic active hepatitis, but no relationship with the score of fibrosis. Among patients treated with interferon-α and with increased fibrogenic activity (indicated by high pretreatment serum levels of procollagen type III peptide), peptide levels were significantly decreased when pretreatment levels were compared with those at 12 months after therapy withdrawal, both in responders to interferon (P=0.022) and non-responders (P=0.012). However, serum procollagen type III peptide levels normalized in 75% of responders to interferon with sustained serological and histological remission of liver disease, but in only 21% of non-responders (P=0.02). These results obtained in a well-defined population suggest that serum procollage type III peptide is a better marker of active fibrogenesis and inflammation than an indicator of the extent of fibrosis, and that interferon may reduce active liver fibrogenesis in chronic hepatitis B indenpendently of its effect on viral replication. However, a consistent proportion (56%) of our chronic hepatitis B patients had normal serum procollagen type III peptide levels at presentation, thus precluding the clinical use of this marker both for diagnosis of liver injury and for monitoring the therapeutic response to interferon.     

Low levels of serum type III procollagen aminoterminal propeptide confirmed type III collagen deficiency in patients without typical clinical symptoms of Ehlers-Danlos type IV

Biochemical analysis of skin samples revealed that the content of type III collagen was greatly reduced in several subjects with joint hypermobility, stretchability and bruisability of skin. When cultured dermal fibroblasts were found to secrete decreased amounts of type III procollagen into medium (about 30-45% the normal amount) and serum type III procollagen aminopropeptide levels were significantly lower than normal values (P less than 0.001). The abnormalities in type III procollagen are in keeping with Ehlers-Danlos type IV although the clinical findings in our patients are not normally associated with this disorder. The results illustrate the clinical heterogeneity of Ehlers-Danlos type IV and the importance of biochemical analysis, such as determination of type III procollagen aminopropeptide levels, to check type III collagen metabolism especially if there is no family history and if correct diagnosis is not reliable by clinical examination alone.     

Increased serum concentration of type IV collagen peptide and type III collagen peptide in hyperthyroidism.

Serum concentration of type IV collagen peptide, the 7S domain of type IV collagen (type IV collagen 7S) and the amino terminal propeptide of type III procollagen (type III procollagen peptide) is thought to be a useful marker of progressive liver disease. In the present study, serum levels of these collagens in patients with thyroidal diseases with normal liver function were assayed. Increased levels in the hyperthyroid state and relatively decreased levels in the hypothyroid state were observed. The increased levels in hyperthyroidism was most prominent in type IV collagen peptide. The increased level became normal in the subsidence of hyperthyroidism by treatment with anti-thyroid drug. A positive correlation between serum type IV collagen peptide levels and serum thyroid hormone levels such as T4, T3, free T4 and free T3 was observed. These facts show that serum type IV collagen peptide may be influenced by not only liver disease but also serum thyroid hormone levels. Type IV collagen peptide may provide a useful biochemical marker of hyperthyroid state.     

Three serum markers of collagen biosynthesis in Nigerians with cirrhosis and various infectious diseases

Serum immunoreactive prolyl hydroxylase protein, galactosylhydroxylysyl glucosyltransferase activity, and the aminoterminal propeptide of type III procollagen (S-Pro(III)-N-P) were measured in twenty patients with cirrhosis and ninety with various infectious diseases, and the values were compared with those in sixty apparently healthy Nigerians. The means for all three markers were elevated significantly in the patients with cirrhosis (P less than 0.001), acute viral hepatitis (P less than 0.001), amoebic liver abscess (P less than 0.001) and the early stages of Schistosoma mansoni infection (P less than 0.001 for S-Pro(III)-N-P, P less than 0.005 for the two other markers). The mean S-Pro(III)-N-P was also distinctly elevated during the early stages of Schistosoma haematobium infection (P less than 0.01) and filariasis (P less than 0.001), whereas none of the three markers was elevated during an acute attack of malaria. Significant correlations were found between the values for the three markers within the groups of patients with cirrhosis, amoebic liver abscess and schistosomiasis, the correlations for the pooled group of all patients being highly significant (P less than 0.001). The data suggest that elevated hepatic collagen formation is found not only in cirrhosis but also in several infectious diseases. The three serum markers may be useful for showing the stages of active collagen formation in various liver diseases and for predicting the development of fibrosis in acute cases if the values remain elevated.     

Evaluation of serum aminoterminal procollagen type III propeptide as an index of portal hypertension and esophageal varices in chronic liver diseases

The concentration of the aminoterminal propeptide of type III procollagen (P-III-P) was determined in serum of cubital vein and hepatic vein of patients with various types of chronic liver diseases (n = 111) and correlated with the portal venous pressure and with the degree of esophageal varices. The P-III-P level in all chronic liver diseases was correlated (rS 0.542, p less than 0.001) with the portal venous pressure, but in liver fibrotic subjects (n = 29) this correlation (rS 0.310) was not significant, in liver cirrhosis (n = 30) the respective correlation was found to be weak (rS 0.333, p less than 0.05) and similar to that in patients with unspecified chronic liver diseases (n = 52) (rS 0.425, p less than 0.01). Sensitivity and specificity of P-III-P at a cut-off concentration of 12 ng/ml for portal hypertension (portal vein pressure 5 mm Hg) are 0.93 and 0.42, respectively, the diagnostic efficiency is 0.67. Predictive values at the same cut-off level of P-III-P and an assumed prevalence of portal hypertension of 50% are 0.62 and 0.85 for the positive and negative test result, respectively. The level of P-III-P is not related to the degree of esophageal varices. The mean P-III-P concentration in the hepatic vein was found to be significantly (p less than 0.001) higher (about 35%) than that in the cubital vein. It is concluded that P-III-P is not an useful parameter for diagnosis of portal hypertension and monitoring of portal vein pressure and of the degree of esophageal varices.     

Diagnostic significance of type IV collagen and hyaluronic acid in the serum of patients with chronic hepatitis C for staging hepatic fibrosis

AIM: To evaluate diagnostic value of serologic fibrosis markers (hyaluronic acid--HA and type IV collagen C-IV) in patients with chronic hepatitis C (CHC) and hepatic cirrhosis (HC). MATERIAL AND METHODS: HA and C-IV were measured in 88 CHC patients with fibrosis stage 1 (n = 63) and 3 (n = 25), 13 patients with acute hepatitis C (AHC), 28 patients with hepatic cirrhosis (HC), 19 patients with pulmonary fibrosis (PF). The control group consisted of 32 healthy subjects. RESULTS: HA concentrations in the serum of CHC patients with mild to severe inflammation and fibrosis (F1 and F3) were normal (100 ng/ml). For HC diagnosis, HA test proved highly sensitive and specific (in HA 100 ng/ml sensitivity was 100%, specificity 84.6%), but this method cannot stage hepatic fibrosis. HA test was inferior to C-IV test. A mean C-IV concentration in the serum of CHC patients at the stage of marked fibrosis (F3) is significantly higher than in F1, in HC (A) patients higher than in patients with CHC F3. CONCLUSION: It is shown than concentration of C-IV above 196 ng/ml can differentiate fibrosis stage 1 from stage 3 with specificity 58.7 and sensitivity 88%.     

Serial determinations of the amino-terminal peptide of type III procollagen in severe chronic active hepatitis

To evaluate the diagnostic significance of the amino-terminal propeptide of procollagen type III (P-III-P) in monitoring chronic liver disease, serum P-III-P concentrations were measured in 46 patients with severe chronic active hepatitis (CAH) at entry and at remission during a therapeutic clinical trial. Coded sera were analyzed for P-III-P concentrations by both a standard radioimmunoassay and a recently developed and potentially more precise radioimmunoassay that uses Fab fragments rather than intact antibodies for binding antigen. As compared with conditions in 22 normal controls, P-III-P concentrations were elevated in 98% and 72% of patients with CAH by use of the standard and Fab radioimmunoassays, respectively. With treatment, P-III-P levels fell at remission to levels that were not significantly different from control values, as measured by both assays. The Fab radioimmunoassay, either alone or combined with the standard radioimmunoassay, provided no advantage over the standard radioimmunoassay alone. Serum P-III-P levels, as measured by either assay, correlated poorly or not at all with standard liver function tests and with histologic grade of disease. These data suggest that P-III-P serum levels are abnormal in severe CAH but normalize when remission of disease has been achieved. Consequently, serum P-III-P levels may be a diagnostic aid in the sequential evaluation of patients with severe CAH requiring treatment, and this test deserves further investigation. In this regard, the standard P-III-P assay has greater diagnostic accuracy than the Fab assay.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cryptogenic chronic active liver disease. Evaluation of serum aminoterminal peptide of type III procollagen as a marker of histological activity

Summary Sera from 64 patients with HBsAg-negative chronic liver disease with or without cirrhosis were investigated for aminoterminal peptide of type III procollagen (sP-III-P) as a suitable marker of hepatic fibrosis; 244 healthy control subjects were included in the study. A close correlation (p<0.01) between sP-III-P levels and histological activity was observed; on the contrary, no correlation was found between the same serum marker of liver fibroplasia and biochemical activity or clinical severity of the disease. We conclude that sP-III-P as a suitable marker of liver overload of collagen fibers is strongly correlated with the histological activity of the disease. Local immune reactions produce soluble substances that might stimulate fibroblastic activity. The test has a significant sensitivity and a very high specificity as a marker of chronic liver disease with histological activity.     

Low production of procollagen III by skin fibroblasts from patients with Ehlers-Danlos syndrome type IV is not caused by decreased levels of procollagen III mRNA

The Ehlers-Danlos syndrome type IV represents a heterogeneous group of diseases, the molecular defect of which seems to reside in a defective synthesis and processing of collagen III. Here we present data concerning both protein and mRNA levels of collagens I and III in cell cultures established from skin of nine patients and six controls. All patients investigated were characterized by a reduced amount of procollagen III in fibroblast cultures. However, the levels of collagen III propeptides, measured by a radioimmunoassay in culture medium of fibroblasts from the patients, were either decreased or in the range of control levels. Using hybridization with cDNA probes specific for pro alpha 1 (I) and pro alpha 1 (III) collagen chains we determined the ratios of procollagens I and III mRNA. Although synthesis of procollagen III was markedly reduced in fibroblasts of all patients studied, no parallel decrease of procollagen III specific mRNA was found. However, two distinctive groups of patients were identified, one with an unaltered ratio of procollagen I/III mRNA and the other which had an even higher proportion of collagen III mRNA.     

Variation in serum type III procollagen peptide with age in healthy subjects and its comparative value in the assessment of disease activity in children and adults with chronic active hepatitis

To determine the comparative value of serum Type III procollagen peptide (PIIIP) in paediatric and adult liver disease we have measured PIIIP in 201 healthy subjects (aged 1 day-77 years) and twenty-one children and five adults with chronic active hepatitis (CAH). Healthy children had significantly higher PIIIP levels than adults (P less than 0.001), with highest values of 298 +/- 88 ng ml-1 (s.d.) in the neonatal period. PIIIP fell to 30.9 +/- 7.0 by 1 year, 19.1 +/- 4.5 by 3 years and rose significantly (P less than 0.01) at puberty. Adult levels (8.3 +/- 3.2) occurred by 16 years of age. Serum PIIIP levels were significantly elevated (P less than 0.001) in adults when they had biochemical and histological evidence of active liver disease but were consistently within the normal range for age in 70% of children with similar hepatic pathology. The minor elevations in PIIIP in the other children were unrelated to clinical, biochemical or histological evidence of active liver disease. While raised PIIIP may be a non-invasive marker of liver disease activity in adults, its value in childrens' disorders appears to be limited by the high levels of PIIIP which occur during growth.     

Aminoterminal propeptides of type III procollagen in human cerebrospinal fluid

The concentrations of aminoterminal propeptides of procollagen type III were determined by radioimmunoassay in the cerebrospinal fluids of 64 patients with various neurological disorders, including 4 infant patients (less than 1 year). In cerebrospinal fluids of adult patients with normal composition (protein, glucose, cell count), adult patients with pathologic composition, and infant patients the peptide levels (mean value +/- S.D.) were 4.07 +/- 1.26 micrograms/l, 8.15 +/- 6.78 micrograms/l, and 56.9 +/- 31.0 micrograms/l, respectively. The concentrations ranged from 1.96 to 265 micrograms/l and were independent of the respective serum propeptide levels. No statistic correlation with other parameters was found. Gel chromatography revealed a high degree of molecular weight heterogeneity, a substantial portion of immunoreactive material was eluted even with the void volume of Sephacryl S 300. Different slopes of radioimmunoinhibition curves indicate heterogenous antigenicity among the propeptides from various patients. Interaction of the propeptides with fibronectin and/or heparin is probably not responsible for the heterogeneity. The diagnostic potential of cerebrospinal fluid propeptide levels for local connective tissue (collagen) turnover remains to be elucidated.     

Collagen metabolism in normal and complicated pregnancy: changes in the aminoterminal propeptide of type III procollagen in serum

The turnover of type III collagen, a major constituent of the myometrium and the uterine cervix, during pregnancy was evaluated by monitoring serum antigens related to the aminoterminal propeptide of type III procollagen. Their concentration increased markedly towards term in most uncomplicated pregnancies, while their size distribution throughout the pregnancy resembled that seen in the sera of normal healthy persons. In some patients, however, the level remained low, indicating interindividual variation in the release into serum and metabolism of the propeptide. There were no distinct changes during or immediately after vaginal delivery. Values exceeding the reference range for uncomplicated pregnancies were found during weeks 28-37 in patients with pre-eclampsia, essential hypertension, intrahepatic cholestasis of pregnancy or twin pregnancy. Thus, pregnancy should be taken into account when evaluating results of the serum assay for the aminopropeptide and the use of this assay as an indicator of pregnancy complications warrants further study.     

Estimation of the production rates of serum aminoterminal propeptide of type III procollagen and laminin in human fibrotic liver

The concentrations of laminin, a high molecular weight non-collagenous glycoprotein of basement membranes, and of the N-terminal propeptide of type III procollagen were determined in the serum of the liver outflow vascular region (hepatic vein) and of a peripheral vein (cubital vein) in patients with chronic liver diseases (fibrosis, cirrhosis, unspecified histology; n = 173), in order to determine their secretion rates from the injured livers. The mean levels of laminin (1.84 kU/l) and of procollagen peptide (28.0 micrograms/l) in hepatic vein were significantly higher (about 9.5% at p less than 0.02, and 37% at p less than 0.001, respectively) than those in the periphery (1.68 kU/l and 20.4 micrograms/l, respectively). In chronic liver diseases, however, laminin and procollagen peptide concentrations in the hepatic vein were lower than or equal to those in the cubital vein in 18% and 27% of patients, respectively. The highest regional differences of the concentrations were noted in cirrhotic subjects. The serum levels of laminin (rs 0.93) and of procollagen peptide (rs 0.73) in hepatic and in cubital vein are highly positively correlated (p less than 0.001), but the levels of procollagen peptide in hepatic vein are only weakly but still significantly statistically related with those of laminin (rs 0.446, p less than 0.001). Similarly, the hepatic-cubital venous concentration differences of both proteins are weakly (rs 0.312) but significantly (p less than 0.001) correlated. On the basis of several assumptions we estimated secretion rates from the livers of 120 U.min-1 for laminin, and 5.7 micrograms.min-1 for procollagen peptide.(ABSTRACT TRUNCATED AT 250 WORDS)     

Type III procollagen peptide and PZ-peptidase serum levels in pre-cirrhotic liver diseases

To obtain a dynamic and non-invasive picture of hepatic fibrosis in pre-cirrhotic liver diseases we measured both the concentration of the N-terminal peptide of procollagen III, as a marker of collagen synthesis, and the activity of PZ-peptidase, an enzyme involved in collagen degradation, in the serum of alcoholic or chronic viral hepatitis patients. Peptide serum levels were similar in chronic persistent hepatitis and controls, but significantly higher in chronic active hepatitis. Chronic persistent hepatitis patients had PZ-peptidase levels higher than controls, but similar to chronic active hepatitis. The increase in collagen synthesis without a parallel increase in collagen degradation seen in chronic active hepatitis could be regarded as a sign of impending cirrhosis, whereas the unbalanced rise in PZ-peptidase observed in chronic persistent hepatitis is consistent with the non-progressive character of this disorder. In alcoholic hepatitis both peptide concentration and PZ-peptidase activity were elevated, thus suggesting that both collagen synthesis and degradation are activated. However, the greater increase in PZ-peptidase than in peptide serum levels seen in some patients seems to indicate a minor tendency to progressive fibrosis or a trend towards resolution. Unlike liver disease patients, normal peptide and PZ-peptidase levels were found in patients with pancreatic fibrosis. Since circulating inhibitors and activators of the PZ-peptidase activity can be excluded, as proved by this study, joint peptide and PZ-peptidase serum measurements would seem to offer a simple reliable non-invasive method for differentiating and monitoring progressive and non-progressive forms of hepatic fibrosis.     

增敏化学发光法测定血清Ⅲ型前胶原

目的 应用增敏化学发光法检测血清Ⅲ型前胶原,了解其检测特性和临床应用前景.方法 对检测血清Ⅲ型前胶原的增敏化学发光法和放射免疫分析(RIA)法进行重复性试验、线性范围试验和回收试验的比较,采用两种方法平行检测108例慢性乙肝病人血清Ⅲ型前胶原含量进行相关性分析,并用增敏化学发光法检测60例正常人血清Ⅲ型前胶原含量.结果 两种方法都有较好的重复性,但增敏化学发光法明显优于RIA法;增敏化学发光法和RIA法具有良好的相关性(R=0.928,p＜0.001,相关方程Y=1.107X-3.312 ,回收率均在95%以上,增敏化学发光法略高于RIA法;增敏化学发光法的线性范围(＜900 μg/L﹞较RIA法(＜600μg/Lμ要宽;增敏化学发光法检测血清Ⅲ型前胶原的参考范围为 4.5～126.5μg/L.结论 增敏化学发光法检测血清Ⅲ型前胶原的准确性和精确度都明显优于RIA法;具有敏感性高、稳定性好、方便快速的优点,适宜在医院推广使用.     

Basement membrane-related and type III procollagen-related antigens in serum of patients with chronic viral liver disease

To assess the significance of serum basement membrane- and type III procollagen-related antigens in reflecting the degree of liver fibrosis, we measured radioimmunologically the concentrations of 7S collagen, laminin fragment P1, and the aminoterminal propeptide of type III procollagen (P-III-P) in serum from 48 patients with chronic viral liver disease: chronic persistent hepatitis (9), chronic active hepatitis (13), chronic active hepatitis with lobular disorganization (17), and liver cirrhosis (9). Concentrations of 7S collagen, laminin P1, and P-III-P in serum were increased in respectively 92%, 69%, and 77% of the patients with both chronic active hepatitis with lobular disorganization and liver cirrhosis. Concentrations of 7S collagen and laminin P1 in serum correlated well (r = 0.65, P less than 0.001, and r = 0.55, P less than 0.001, respectively) with the histological grade of liver fibrosis, whereas P-III-P correlated only weakly (r = 0.33, P less than 0.05). Evidently, measurement of serum 7S collagen is a reliable noninvasive test for detection of fibrosis in chronic viral liver disease.