Variations in the glycoforms of serum alpha 1-antichymotrypsin in liver diseases and after liver transplantation

1. Using crossed immunoaffinity electrophoresis with free concanavalin A in the first dimension, we studied the microheterogeneity of alpha 1-antichymotrypsin due to various glycoforms in sera from patients with various liver diseases and after liver transplantation. 2. Studies by isoelectric focusing and immunoblotting and by crossed immunoelectrophoresis without concanavalin A in the first dimension allowed us to show that there is no dramatic variation in electrophoretic heterogeneity of alpha 1-antichymotrypsin in the serum of patients with liver diseases or after liver transplantation when compared with that of normal subjects. Therefore the heterogeneity observed in crossed immunoaffinity electrophoresis is due to various interactions with concanavalin A. 3. The results were expressed as the ratio of concanavalin A non-reactive glycoforms plus concanavalin A weakly reactive glycoforms to concanavalin A reactive glycoforms, called R alpha 1-ACT. R alpha 1-ACT was significantly higher in patients with cirrhosis (n = 53) when compared with normal subjects (n = 30). The median R alpha 1-ACT was 1 (range 0.72-1.25) in normal subjects. It was 1.6 (range 1.18-3.02), 1.45 (range 0.65-4.12) and 2.24 (range 1.03-19) in cirrhosis of Child's grade A, B and C, respectively. There was a dramatic decrease in glycoforms with mostly biantennary glycans in some patients with Child's grade C cirrhosis. Serum levels of alpha 1-antichymotrypsin were lower than normal only in some patients with Child's grade C cirrhosis. 4. Among the patients with acute viral hepatitis studied (n = 17), five were studied longitudinally.(ABSTRACT TRUNCATED AT 250 WORDS)

Interferon for non-A, non-B chronic hepatitis. A meta-analysis of randomised clinical trials

We reviewed randomised clinical trials evaluating the effect of lymphoblastoid or recombinant alpha-interferon in non-A, non-B chronic hepatitis. The outcomes assessed were the rates of serum alanine aminotransferase normalization and relapse during and after stopping interferon. Data were pooled by meta-analysis and a 50% overall rate difference, favouring treated patients, was found. Results showed homogeneity in direction of treatment effect both after short-term (2-6 months, greater than or equal to 2 mega-units thrice weekly) and long-term (9-18 months, variable dose) interferon course. Moreover, results did not change when type of publication (abstracts vs. full reports) and treatment duration or schedule were accounted for. About 50% of patients originally responding to treatment relapsed within 6 months of either dose reduction or stopping interferon, thus suggesting that only in about one out of four patients is benefit from treatment sustained up to 1 year. We conclude that larger trials are needed to identify an optimal schedule of treatment and to evaluate predictors of interferon effectiveness in patients with non-A, non-B chronic hepatitis.

[2'-5' oligoadenylate synthetase activity in patients with acute viral hepatitis and chronic type B hepatitis, and its clinical significance]

The levels of 2'-5' oligoadenylate synthetase activity (2-5AS) were measured in the lymphocytes and sera of 32 patients with acute viral hepatitis and 20 patients with HBeAg positive chronic type B hepatitis, and the relationship between the effectiveness of interferon (IFN) therapy and 2-5AS reactivity was then studied. The lymphocyte 2-5AS (L.2-5AS) and the serum 2-5AS (S.2-5AS) levels in patients with any type of acute viral hepatitis at the acute stage were significantly higher than in the healthy subjects. The 2-5AS level in cases of acute type A viral hepatitis was significantly higher than in type B and type non A non B hepatitis. However, no significant difference in the 2-5AS levels between type B hepatitis and type non A non B hepatitis was observed. After recovery, the L.2-5AS and S.2-5AS levels decreased in patients with any type of acute viral hepatitis. No significant difference between the L.2-5AS level in healthy subjects and patients with chronic type B hepatitis was observed. The S.2-5AS level was significantly higher in patients with chronic type B hepatitis than in healthy subjects. During IFN administration, the L.2-5AS and S.2-5AS levels increased, with the maximum level and maximum rate of increase obtained on the 3rd day with respect to the L.2-5AS, and after one week with respect to the S.2-5AS. Of the 20 patients with chronic type B hepatitis with positive HBe antigen, 11 showed normalization of DNA-P, 4 disappearance of HBe antigen and 2 seroconversion of HBe antigen. In cases with a higher maximum rate of increase of the L.2-5AS, the effect of IFN therapy was observed to be greater.

Detection of 2',5' oligoadenylate synthetase activity in acute viral hepatitis with special reference to histologic features in the acute stage

We measured the sequential changes in 2',5' oligoadenylate synthetase activity in 21 patients with acute viral hepatitis (5 with type A, 6 with type B, and 10 with type non-A, non-B hepatitis) by radioimmunoassay. Liver biopsies were performed during the acute phase in all patients. Among patients with acute hepatitis A and B, the 2',5' oligoadenylate synthetase levels were transiently elevated at the time of the peak alanine aminotransferase level in the patients in whom a liver biopsy showed acute hepatitis or non-specific reactive hepatitis. Of 10 patients with acute non-A, non-B hepatitis, 4 showed a similar 2',5' oligoadenylate synthetase activity pattern and liver histology to those observed in acute hepatitis A and B. In the remaining 6, the 2',5' oligoadenylate synthetase levels remained elevated for 3.5 to 6 months while the alanine aminotransferase was elevated. Liver biopsy in these patients showed chronic hepatitis. Persistent detection of raised 2',5' oligoadenylate synthetase activity levels during the acute stage of non-A, non-B hepatitis may thus be an indicator of progression of the disease.

Changes of serum cholinesterase isozyme patterns in liver diseases

A simple method was established for the separation and identification of serum cholinesterase (SChE) isozymes by using gradient polyacrylamide gel electrophoresis and densitometric scanning. With this method, SChE isozyme patterns of 39 healthy adults and 232 patients with liver diseases were studied. 9 to 11 bands of SChE were demonstrated in healthy adults. The activities increasing in Band 1 and decreasing or disappearing in Bands 2, 3, 4 and 5 were found in most patients with liver diseases in comparing with the control. It showed that the activity decreasing is correlated closely with the severity of liver diseases.

Measurement of serum alcohol dehydrogenase activity at different pH-values during the course of viral hepatitis in children

Serum alcohol dehydrogenase activity was estimated at pH 10.4 (optimum for the typical liver isoenzyme), 8.8 (optimum for atypical liver isoenzyme), at the physiological serum pH of 7.4, and at pH 9.2, with a view to obtaining the greatest possible difference between patients and controls. Measurements were performed on the sera of 39 children aged from 2 to 13 years, using the Technicon analyzer RA-1000 with the continuously measuring method of Bonnichsen & Brink. Blood sera were tested at the onset of viral hepatitis, in the first week of hospitalization, and three times thereafter at intervals of 7 to 9 days. During the illness, the activity of serum alcohol dehydrogenase, measured at different pH-values, was higher than that of controls. The ratio of activity at pH 10.4 to activity at pH 8.8 in the sera differed from that previously reported for liver cells. The highest increase in alcohol dehydrogenase activity was at pH 9.2. The diagnostic sensitivity of alcohol dehydrogenase determination at this pH is lower than that of alanine aminotransferase, gamma-glutamyltransferase and aspartate amino-transferase, but higher than that of lactate dehydrogenase, alkaline phosphatase and bilirubin; alcohol dehydrogenase activity also shows the best correlation with the activity of gamma-glutamyltransferase.

Clearance of argininosuccinate synthetase from the circulation in acute liver disease

Argininosuccinate synthetase is an enzyme which has been found to be a specific marker for liver damage. In patients with acute hepatitis, the concentration in serum increases at the onset of the disease, but later decreases more quickly, so that the time required for normalization is shorter than that of alanine aminotransferase. This is probably caused by rapid clearance of argininosuccinate synthetase from the serum. Rapid clearance was demonstrated in experimental animals given purified enzymes intravenously. Argininosuccinate synthetase disappeared from the serum with a half life of about 15 min, while the half lives of alanine aminotransferase and aspartate aminotransferase were 4 and 5 h, respectively, under the same conditions.

[Dipeptidyl aminopeptidase IV in hospitalized patients and in galactosamine hepatitis of the rat: Activity and lectin affinity chromatography in serum and hepatic plasma membranes]

The activity of dipeptidyl aminopeptidase IV was studied in the sera of 378 hospitalized patients. The mean activity of dipeptidyl aminopeptidase IV was elevated significantly in patients with neoplasmata and hepatitis, but not in patients with liver cirrhosis. Significant correlations (p less than 0.001) existed with gamma-glutamyl transferase, glutamate dehydrogenase, alkaline phosphatase and leucine aminopeptidase. A significant correlation with lactate dehydrogenase existed only in patients with neoplasmata. Principal component analysis, performed with aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, leucine aminopeptidase, lactate dehydrogenase and dipeptidyl aminopeptidase IV, revealed correlations between the activities of aspartate aminotransferase and alanine aminotransferase, and between alkaline phosphatase and leucine aminopeptidase, but neither dipeptidyl aminopeptidase IV nor lactate dehydrogenase showed any correlation with either of these two groups. In lectin affinity chromatography with concanavalin A and wheat germ lectin sepharose, serum dipeptidyl aminopeptidase IV from liver cirrhosis patients showed the same binding pattern as that from healthy subjects. The activity and glycosylation of dipeptidyl aminopeptidase IV in serum and hepatic plasma membranes was investigated in rats, following the induction of hepatitis with galactosamine. In the serum, dipeptidyl aminopeptidase IV activity was elevated as early as 6 h after galactosamine injection, and the elevated activity persisted until the 7th day. At the same time dipeptidyl aminopeptidase IV activity was also elevated in the hepatic plasma membrane. Ninety eight percent of hepatic dipeptidyl aminopeptidase IV bound to concanavalin A as well as to wheat germ lectin and this value was unchanged during hepatitis. In the serum of control rats, 90% of dipeptidyl aminopeptidase IV bound to concanavalin A but only 39% to wheat germ lectin.(ABSTRACT TRUNCATED AT 250 WORDS)

[Chronic hepatitis non-A, non-B hepatitis: a clinical and morphologic study]

Few data on chronic non-A, non-B hepatitis (NANB-CH) have been published so far in our country. We have studied 85 patients classified into four groups: I. post-transfusional (PT), 35 patients (41.2%); II. risk group (GR), including health professionals and drug addicts, 11 (12.9%); III. sporadic with a well defined beginning (EBD), 19 (22.4%) and IV. sporadic with ill-defined beginning (END), 20 (23.5%). The mean age in group I was significantly higher than in groups II and III. A polyphasic pattern of serum aminotransferases and severe histological forms were observed in all groups. It is concluded that the way of infection has probably no prognostic importance.

A review of donor alanine aminotransferase testing. Implications for the blood donor and practitioner

To reduce the incidence of post-transfusion non-A, non-B hepatitis, the American Association of Blood Banks has required that serum alanine aminotransferase activity be used to screen blood donors. Consequently, approximately 2% to 3% of all blood donations will be discarded owing to an elevated alanine aminotransferase level. In addition, approximately 0.7% of blood donors will be notified of an abnormal alanine aminotransferase result. While some of these donors may have viral hepatitis, factors such as the donor's age, gender, body weight, ethnic background, alcohol intake, diet, and exercise must also be considered when interpreting an elevated alanine aminotransferase level. Donors with significant or persistently elevated alanine aminotransferase levels should have their conditions evaluated so that treatable diseases can be recognized and/or treated.

[N-acetyl-beta-D-glucosaminidase in jaundice syndrome]

The seric activity of the enzyme NAG (N-acetyl-beta-D-glucosaminidase) was studied in 3 groups of patients with jaundice of different etiology (extrahepatic, intrahepatic and acute hepatitis) and in a control group, in order to observe the discrimination capacity of this enzyme in each group. After the use of a fluorimetric method, the results were exposed, applying the statistical test, comparing different variables; the results are discussed and we conclude that NAG is an enzyme of easy detection and low cost to be included in the group of tests to study the biological pattern of jaundice.

Interferon-associated lymphocyte 2',5'-oligoadenylate synthetase in acute and chronic viral hepatitis

Basal levels of the interferon-associated enzyme 2',5'-oligoadenylate synthetase were studied in lymphocytes of 46 patients with acute viral hepatitis and in 46 patients with chronic hepatitis B. Measurement of in vitro production of 2',5'-oligoadenylate synthetase following overnight incubation of lymphocytes with exogenous interferon was used to assess functional capacity of the lymphocyte interferon system. In acute hepatitis patients, an early but transient elevation of 2',5'-oligoadenylate synthetase was observed; the mean level at 1 week was significantly greater than the mean level at 4 weeks after the onset of their illness (p less than 0.01). Serial 2',5'-oligoadenylate synthetase levels did not identify those patients who were to progress to chronic hepatitis. Patients with chronic hepatitis B infection, regardless of background liver histology, generally had normal basal lymphocyte 2',5'-oligoadenylate synthetase levels. In both acute viral hepatitis and chronic hepatitis B, there was an inverse correlation between basal 2',5'-oligoadenylate synthetase level and 2',5'-oligoadenylate synthetase response to overnight incubation with interferon, a finding that suggested a transient down-regulation of interferon responsiveness. These findings provided no support for the hypothesis that there is an inherent or persistently induced deficiency in the interferon system in acute or chronic hepatitis B.

Clinical significance of serum guanase activity in various liver diseases

Serum guanase activity was measured using a sensitive colorimetric method in patients with liver diseases. Guanase activity was correlated with GPT, GOT in acute viral hepatitis and chronic hepatitis, however, in liver cirrhosis and hepatocellular carcinoma it was correlated with total bilirubin as well as aminotransferases. In addition, the GPT-to-guanase ratio differed chronic hepatitis from liver cirrhosis. These findings suggest that determination of guanase and aminotransferases in useful in differentiation of liver diseases as well as assessing liver damage.

Delta 4-3-oxosteroid 5 beta-reductase deficiency described in identical twins with neonatal hepatitis. A new inborn error in bile acid synthesis

A new inborn error in bile acid synthesis, manifest in identical infant twins as severe intrahepatic cholestasis, is described involving the delta 4-3-oxosteroid 5 beta-reductase catalyzed conversion of the key intermediates, 7 alpha-hydroxy-4-cholesten-3-one and 7 alpha,12 alpha-dihydroxy-4-cholesten-3-one for chenodeoxycholic and cholic acid synthesis, to the respective 3 alpha-hydroxy-5 beta (H) products. This defect was detected by fast atom bombardment ionization-mass spectrometry from an elevated excretion and predominance of taurine conjugated unsaturated hydroxy-oxo-bile acids. Gas chromatography-mass spectrometry confirmed these to be 7 alpha-hydroxy-3-oxo-4-cholenoic and 7 alpha,12 alpha-dihydroxy-3-oxo-4-cholenoic acids (75-92% of total). Fasting serum bile acid concentrations were greater than 37 mumol/liter; chenodeoxycholic acid was the major bile acid, but significant amounts of allo(5 alpha-H)-bile acids (approximately 30%) were present. Biliary bile acid concentration was less than 2 mumol/liter and consisted of chenodeoxycholic, allo-chenodeoxycholic, and allo-cholic acids. These biochemical findings, which were identical in both infants, indicate a defect in bile acid synthesis involving the conversion of the delta 4-3-oxo-C27 intermediates into the corresponding 3 alpha-hydroxy-5 beta(H)-structures, a reaction that is catalyzed by a delta 4-3-oxosteroid-5 beta reductase enzyme. This defect resulted in markedly reduced primary bile acid synthesis and concomitant accumulation of delta 4-3-oxo-and allo-bile acids. These findings indicate a pathway in bile acid synthesis whereby side chain oxidation can occur despite incomplete alterations to the steroid nucleus, and lend support for an active delta 4-3-oxosteroid 5 alpha-reductase catalyzing the conversion of the delta 4-3-oxosteroid intermediates to the respective 3 alpha-hydroxy-5 alpha(H)-structures.

Ratio of serum aspartate to alanine aminotransferase in chronic hepatitis. Relationship to cirrhosis

The ratio of the serum aspartate to alanine amino-transferase levels (AST/ALT) is often used as a clue to the etiology of the underlying liver disease. This ratio is usually greater than 2.0 in alcoholic liver disease and less than 1.0 in patients with chronic hepatitis and chronic cholestatic syndromes. We analyzed the AST/ALT ratio in 177 patients with various forms of nonalcoholic chronic liver disease who underwent medical evaluation and percutaneous liver biopsy. In the majority of cases of chronic viral hepatitis, the AST/ALT ratio was less than 1.0. However, there was a statistically significant correlation between the AST/ALT ratio and the presence of cirrhosis. Among 100 patients with chronic type B hepatitis, the mean AST/ALT ratio was 0.59 in those without cirrhosis and 1.02 in those with cirrhosis. Furthermore, the AST/ALT ratio often rose to greater than 1.0 when cirrhosis first became manifest. Thus, the finding of an AST/ALT ratio of greater than 1.0 in a patient with nonalcoholic liver disease should suggest the presence of cirrhosis. In addition, the use of the AST/ALT ratio as a means of separating alcoholic and nonalcoholic liver disease must be tempered with the knowledge that this ratio may be less helpful in the presence of cirrhosis.

2',5'-Oligoadenylate synthetase activity in the liver and peripheral blood mononuclear cells of chronic hepatitis patients

The in vivo activity of the interferon (IFN) system was studied in 39 patients with chronic hepatitis B (CHB) and in 24 patients with chronic hepatitis type non-A, non-B (CHNANB). 2',5'-Oligoadenylate synthetase (2-5 A synthetase) activity was monitored in the liver and peripheral blood mononuclear cells (PBMCs). Liver 2-5 A synthetase activity was higher in HBeAg-positive CHB and CHNANB patients than in HBeAg-negative CHB patients or controls. The IFN system appeared to be preserved in CH patients. In HBeAg-positive CHB patients the changes in DNA-P activity indicated that PBMC 2-5 A synthetase activity depended on replication of hepatitis B virus(HBV). Exogenous IFN administration in patients with HBeAg-positive CHB significantly elevated 2-5 A synthetase activity in PBMCs, as well as in the liver. In measurement of 2-5 A synthetase activity of CHB patients, the IFN system seems to be important in regulating HBV replication and in the exacerbation of liver inflammatory activity.

Lack of reverse transcriptase activity in serum in sporadic post-transfusional and presumed epidemic or water-borne forms of severe non-A, non-B hepatitis

Reverse transcriptase (RT) activity was not detected in any serum sample taken from 22 patients with mainly severe non-A, non-B hepatitis (NANBH), using two assays selected to cover the range of known human and animal retroviruses. The study included patients with fulminant and sub-acute hepatic failure, which was was attributed to sporadic, post-transfusional, and presumed epidemic or water-borne epidemiological forms of NANBH. Although we cannot exclude the possibility that some of the agents implicated in NANBH are retroviruses, our negative findings suggest that other agents may be involved at least in the severe forms of NANBH.