Search

There was evidence that perinuclear antineutrophil cytoplasmic antibodies (pANCA) in autoimmune liver diseases react with human beta-tubulin-5 (TBB5). Here, we reevaluate the specificity and clinical relevance of anti-TBB5 antibodies. Patients with untreated autoimmune hepatitis (AIH; n = 53), AIH under immunosuppressive therapy (AIH-IS; n = 125), primary sclerosing cholangitis (PSC; n = 40), primary biliary cholangitis (PBC; n = 250), nonautoimmune liver diseases (n = 158), inflammatory bowel diseases (IBD; n = 30), and healthy individuals (n = 62) were tested by enzyme-linked immunosorbent assay for IgG- and IgA-antibodies against recombinant human TBB5. pANCA were detected by immunofluorescence test. Sera were absorbed with TBB5 coupled to cyanogen bromide-activated sepharose. Prevalence and reactivity of IgG anti-TBB5 were significantly higher in patients with untreated AIH (68%; arbitrary units [AU] median: 369) than in PSC (28%; AU median: 84, P < 0.001), other liver diseases (14%; AU median: 185, P < 0.0001), IBD (3%; AU median: 111, P < 0.0001), and healthy controls (3%; AU median: 135; P < 0.0001). Anti-TBB5 did not correlate with pANCA, and immunoprecipitation with TBB5 did not abolish pANCA reactivity. In untreated AIH, anti-TBB5-reactivity was significantly higher than in AIH-IS. Transaminases decreased under IS preferentially in anti-TBB5-negative patients. There was no correlation between anti-TBB5-reactivity and histological stages. IgA-anti-TBB5 was mainly found in alcohol-associated liver disease (ALD; 39%). Our data do not support TBB5 as an autoantigenic target of pANCA. However, IgG-anti-TBB5 showed high specificity for (untreated) AIH. While they did not correlate with histological and laboratory parameters, their presence may indicate a poor response to IS., (© The Author(s) 2023. Published by Oxford University Press on behalf of the British Society for Immunology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Introduction: Regulatory CD4 + T cells (Tregs) are pivotal for inhibition of autoimmunity. Primary sclerosing cholangitis (PSC) is an autoimmune cholestatic liver disease of unknown etiology where contribution of Tregs is still unclear. Activation of the JAK-STAT pathway critically modifies functions of Tregs. In PSC, we studied activation of STAT proteins and Treg functions in response to cytokines., Methods: In 51 patients with PSC, 10 disease controls (chronic replicative hepatitis C), and 36 healthy controls we analyzed frequencies of Foxp3 + CD25 + CD127 low CD4 + Tregs, their expression of ectonucleotidase CD39, and cytokine-induced phosphorylation of STAT1, 3, 5, and 6 using phospho-flow cytometry. In parallel, we measured cytokines IFN-gamma, interleukin (IL)-6, IL-2, and IL-4 in serum via bead-based immunoassays., Results: In patients with PSC, ex vivo frequencies of peripheral Tregs and their expression of CD39 were significantly reduced (p < .05 each). Furthermore, serum levels of IFN-gamma, IL-6, IL-2, and IL-4 were markedly higher in PSC (p < .05 each). Unlike activation of STAT1, STAT5, and STAT6, IL-6 induced increased phosphorylation of STAT3 in Tregs of PSC-patients (p = .0434). Finally, STAT3 activation in Tregs correlated with leukocyte counts., Conclusions: In PSC, we observed enhanced STAT3 responsiveness of CD4 + Tregs together with reduced CD39 expression probably reflecting inflammatory activity of the disease., (© 2024 The Authors. Immunity, Inflammation and Disease published by John Wiley & Sons Ltd.)

Background: Inflammatory bowel diseases (IBDs) are often associated with altered liver function tests (LFTs). There is little data on the relationship between abnormal LFT and IBD. Our study aimed to evaluate the prevalence and etiology of elevated LFT in patients with ulcerative colitis (UC) and to determine whether there is an association with clinical and demographic parameters., Methods: The clinical records of the Gastroenterology Outpatients Clinic at a single center were reviewed and screened for patients with UC from 2005 to 2014. In total, 263 patients were included. Patients with Crohn's disease (CD), colitis indeterminate, and colitis of other origins were excluded. Abnormal LFT and liver injuries were analyzed., Results: A cohort of 182 patients was analyzed (114 males, 68 females; mean age = 50.2 ± 16.1 years). 58 patients had already been diagnosed with a hepatobiliary disorder. Patients with a known hepatobiliary disorder suffered from UC for a significantly longer duration. Elevated LFT in patients without known hepatobiliary disorders was 69.4%. Liver injury was found in 21.8%. A transient increase in abnormal LFT was shown in 59 patients (68.6%), a persistent increase was found in 27 patients (31.4%). Treatment with thiopurines was a risk factor for persistent elevated LFT ( p = 0.029), steroids had a protective impact ( p = 0.037)., Conclusion: This study clearly highlights the importance of screening for hepatobiliary disorders and abnormal LFT in patients with UC, as the prevalence of hepatobiliary disorders and abnormal LFT is detected very often among this patient group., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Stratmann, Aydolmus, Gu, Heling, Spengler, Terjung, Strassburg, Vollenberg, Blumenstein and Trebicka.)