Worse Response to Ursodeoxycholic Acid in Primary Biliary Cholangitis Patients with Autoimmune Hepatitis Features.

BACKGROUND: There is limited evidence on the treatment response of primary biliary cholangitis (PBC) with autoimmune hepatitis (AIH) features but not meet the criteria of PBC-AIH syndromes. The aim of this study was to elucidate the clinical characteristics of PBC patients with features of AIH. METHODS: We included patients with diagnostic criteria of PBC. All patients were treated with ursodeoxycholic acid (UDCA) and without immunosuppressive agents for >1 year. The biochemical response was evaluated at 1 year after the treatment of UDCA. RESULTS: Among 432 patients with PBC, 166 (38.4%) patients did not achieve biochemical response within 1 year of UDCA treatment. Nonresponders had a lower albumin level and higher immunoglobulin G, alanine transaminase (ALT), alanine aminotransferase (AST), alkaline phosphatase, glutamyl transpeptidase and total bilirubin levels (p < 0.05). The response rates were significantly lower in patients with elevated level of IgG or ALT or AST. Moreover, the higher the IgG or AST level was, the lower the response rate was in patients with PBC, regardless of cirrhosis. For patients with cirrhosis, there was no differences among patients with different levels of ALT. Patients in the PBC with AIH features group had a significant lower response rate than patients in the PBC-only group. Among the 139 patients who underwent liver biopsy, 54 were nonresponsive to UDCA and 48 (88.9%) shown mild interface hepatitis. CONCLUSION: In conclusion, PBC patients with AIH features had a worse response to UDCA therapy.

Primary biliary cholangitis with normal alkaline phosphatase: A neglected clinical entity challenging current guidelines.

BACKGROUND & AIM: The diagnosis of primary biliary cholangitis (PBC), an uncommon immune-mediated cholestatic liver disease, is based on positive circulating anti-mitochondrial (AMA) and/or PBC-specific anti-nuclear autoantibodies (ANA), coupled with elevated serum alkaline phopsphatase (ALP) levels. Timely initiation of treatment with ursodeoxycholic acid prevents progression to cirrhosis and liver failure. We aimed at investigating liver histology in patients with normal ALP level and positive AMA and/or PBC-specific ANA. METHODS: We searched the Swiss PBC Cohort Study database, which includes subjects with positive PBC autoimmune serology and normal ALP levels, for patients who underwent a liver biopsy. Histological slides were centrally reviewed by an expert liver pathologist, and sera were centrally re-tested for AMA and ANA. RESULTS: 30 patients were included; 90% females, median age 53 (range 27-72) years. Twenty-four (80%) had liver histology typical for (n = 2), consistent with (n = 16) or suggestive of (n = 6) PBC, including three of four AMA-negative ANA-positive patients. Among 22 ursodeoxycholic acid treated patients, 14 had elevated GGT levels before treatment; a significant decrease of the median GGT level between pre- (1.46 x ULN) and post- (0.43 x ULN) treatment (p = 0.0018) was observed. CONCLUSIONS: In our series, a high proportion of AMA positive patients with normal ALP levels have PBC. For the first time we show histological diagnosis of PBC in AMA-negative/PBC-specific ANA-positive subjects and the potential role of GGT as a biomarker in PBC patients with normal baseline ALP levels. Current guidelines for the diagnosis of PBC do not cover the whole extent of PBC presentation, with important clinical implications in terms of timely treatment initiation.

Idiotype-anti-idiotype-based noncompetitive enzyme-linked immunosorbent assay of ursodeoxycholic acid 7-N-acetylglucosaminides in human urine with subfemtomole range sensitivity.

We have established a noncompetitive enzyme-linked immunosorbent assay (ELISA) for the group-specific determination of 7-N-acetylglucosaminide of ursodeoxycholic acid (UDCA 7-NAG) and its glycine- and taurine-amidated metabolites (UDCA 7-NAGs) in human urine. These metabolites are expected to be a diagnostic marker for patients with primary biliary cirrhosis (PBC). This assay is based on the idiotype-antiidiotype reaction where the analyte was captured by an excess amount of anti-UDCA 7-NAG antibody, and the unoccupied paratope was blocked with a beta-type antiidiotype antibody. The hapten-occupied antibody was then selectively detected with a biotin-labeled alpha-type antiidiotype antibody. The amount of bound biotin, increasing proportionally to the increase in the analyte, was colorimetrically determined using a peroxidase-labeled streptavidin. This assay provided subfemtomole range sensitivity (detection limit 118 amol) and allowed group-specific measurement of the UDCA 7-NAGs in urine without any pretreatment. The present ELISA revealed that significant amounts of UDCA 7-NAGs are excreted even in healthy subjects. Daily excretion rates for healthy males were determined to be 246+/-184 (S.D.) microg (n=5) as the glycine-amidated UDCA 7-NAG equivalent. Randomly collected urine specimens from patients with PBC (n=7) were also measured, and the assay values (standardized to creatinine excretion) ranged from 1.82 to 13.4 microg/mg Ucre with the average of 5.41+/-4.53 (S.D.) microg/mg Ucre.

Monoclonal antibodies generated against an affinity-labeled immune complex of an anti-bile acid metabolite antibody: an approach to noncompetitive hapten immunoassays based on anti-idiotype or anti-metatype antibodies.

Conventional immunoassays for haptens such as steroids and synthetic drugs are dependent on the competitive reaction between an unlabeled antigen (analyte) and a labeled antigen against a limited amount of anti-hapten antibody. Although noncompetitive immunoassay procedures such as two-site immunometric assays offer a much higher sensitivity, direct application of this principle to haptens has been difficult due to their small molecular mass precluding simultaneous binding by two antibody molecules. Here, we have attempted to develop a noncompetitive immunoassay system based on anti-idiotype or anti-metatype antibodies. Ursodeoxycholic acid 7-N-acetylglucosaminide (UDCA 7-NAG), which is a bile acid metabolite (molecular weight, 595.8), was selected as the model hapten. A/J mice were immunized with a monoclonal antibody against UDCA 7-NAG, which had been affinity-labeled with a relevant hapten derivative. The fusion between the immune spleen cells and P3/NS1/1-Ag4-1 myeloma cells yielded four kinds of alpha-type and two kinds of beta-type monoclonal anti-idiotype antibodies, each recognizing the framework region and paratope of the anti-hapten antibody. The use of a selected combination between alpha-type and beta-type antibodies together with the anti-hapten antibody provided a noncompetitive assay system with a subfemtomole order sensitivity (detection limit, 118 amol) and a practical specificity.

A monoclonal antibody-based enzyme-linked immunosorbent assay of ursodeoxycholic acid 3-sulfates in human urine.

Sulfation of the 3-hydroxy group is assumed to be a major metabolic route of ursodeoxycholic acid (UDCA) which is used for treating various hepatobiliary diseases. We have developed a sensitive enzyme-linked immunosorbent assay (ELISA) for determining the total amount of nonamidated, glycine- and taurine-amidated ursodeoxycholic acid 3-sulfates (UDCA 3-Suls) using a newly established monoclonal antibody. In this study, 12 kinds of antibody-secreting hybridoma clones were generated by a fusion experiment between P3/NS1/1-Ag4-1 myeloma cells and the spleen cells from a BALB/c or an A/J mouse which had been immunized with a conjugate of nonamidated UDCA 3-Sul and bovine serum albumin. One of the monoclonal antibodies, Ba-10 (gamma2a, kappa), had suitable binding properties for clinical application, which was group-specific to the UDCA 3-Suls, and showed negligible cross-reactivities with various related bile acids including potentially interfering compounds, namely, the unconjugated UDCA, UDCA 7-N-acetylglucosaminide, the 3-sulfates of cholic acid, chenodeoxycholic acid and deoxycholic acid. The antibody Ba-10 allowed us to develop a sensitive competitive ELISA system whose measurable range was approximately 2-200 pg per assay. A serial dilution study indicated that the ELISA enables the direct measurement of the UDCA 3-Suls in human urine before and after the administration of exogenous UDCA. The daily urinary excretion rate of UDCA 3-Suls from healthy male volunteers (n = 5) was determined to be a mean of 131 +/- 61.2 (SD) microgram as the nonamidated UDCA 3-Sul equivalent.

Ursodeoxycholic acid therapy in hepatobiliary disease.

Ursodeoxycholic acid is a hydrophilic bile acid that under normal circumstances represents a small fraction of the bile acid pool in humans. It is effective in dissolving cholesterol gallstones in appropriately selected patients. Ursodeoxycholic acid improves serum alkaline phosphatase and aminotransferase levels in primary biliary cirrhosis, but its effects on rates of liver transplantation and death are less certain. Ursodeoxycholic acid has had promising [corrected] effects in several other cholestatic liver diseases, such as cystic fibrosis and intrahepatic cholestasis of pregnancy, but data are too preliminary to make recommendations about its routine use in these conditions. Its effects are mediated by amelioration of damage to cell membranes caused by retained toxic bile acids. Ursodeoxycholic acid improves biliary secretion of bile acids, may improve bile flow, and it has immunomodulatory properties that may reduce immune-mediated liver damage. However, its use in the treatment of cholestatic liver disease remains uncertain pending additional randomized trials.

Successful immunomodulating in AIDS patients with ursodeoxycholic acid--a pilot study.

Based on the positive therapeutic results with ursodeoxycholic acid (UDCA) in patients with primary biliary cirrhosis, in whom we observed a clinical improvement in conjunction with the normalization of the low pretreatment dipeptidyl peptidase (DPIV, CD26) expression of peripheral blood lymphocytes (PBL), we hypothesized that the very low DPIV expression in AIDS patients could be positively influenced by UDCA. Four young male AIDS patients were therefore treated with 750 mg of UDCA for 4 months. The low CD26 expression (2-8% of the PBL versus 18-28% in healthy controls) at the beginning of the study rose to 10-16% after UDCA therapy. Simultaneously we observed a two-to-three-fold elevation of the absolute number of lymphocytes as well as a slight increase of CD4+ cells. These effects were similar in all examined patients. Further investigations should be conducted on this potentially beneficial effect of UDCA.

Production and characterization of group-specific monoclonal antibodies recognizing nonamidated, glycine- and taurine-amidated ursodeoxycholic acid 7-N-acetylglucosaminides.

Ursodeoxycholic acid 7-N-acetylglucosaminides (UDCA 7-NAGs) are novel conjugated metabolites whose urine levels are expected to be a specific diagnostic index for primary biliary cirrhosis. To obtain a specific antibody which is useful for developing immunochemical analytical methods of UDCA 7-NAGs, a variety of monoclonal antibodies have been generated. Spleen cells from an A/J mouse, which had been immunized with a conjugate of nonamidated UDCA 7-NAG and bovine serum albumin, were fused with P3/NS1/1-Ag4-1 myeloma cells. After screening by an enzyme-linked immunosorbent assay (ELISA) using a beta-galactosidase-labeled antigen, thirteen kinds of antibody-secreting hybridoma clones were established. Binding properties of these monoclonal antibodies were investigated in detail by ELISA. One of these antibodies, Ab-#8 (gamma1, kappa) had the most favorable characteristics for clinical application, which was group-specific to the 7-NAG conjugates of nonamidated, glycine- and taurine-amidated UDCAs providing a highly sensitive dose-response curve for each conjugate (midpoint 17 pg per assay for nonamidated UDCA 7-NAG). Cross-reactivities with eleven kinds of bile acids, including some potential interfering metabolites as UDCA 3-sulfate, were negligibly low. By using direct ELISA based on Ab-#8, daily urinary excretion rates of UDCA 7-NAGs of two healthy subjects were determined to be 1030 and 469 microg as GUDCA 7-NAG equivalent.