nDsbD: a redox interaction hub in the Escherichia coli periplasm

Abstract.: DsbD is a redox-active protein of the inner Escherichia coli membrane possessing an N-terminal (nDsbD) and a C-terminal (cDsbD) periplasmic domain. nDsbD interacts with four different redox proteins involved in the periplasmic disulfide isomerization and in the cytochrome c maturation systems. We review here the studies that led to the structural characterization of all soluble DsbD domains involved and, most importantly, of trapped disulfide intermediate complexes of nDsbD with three of its four redox partners. These results revealed the structural features enabling nDsbD, a ‘redox hub' with an immunoglobulin-like fold, to interact efficiently with its different thioredoxin-like partner

Mycophenolate mofetil as second line treatment in autoimmune hepatitis – A retrospective single center analysis

Background: Most patients with autoimmune hepatitis respond to standard treatment with steroids and azathioprine. While the disease is usually fatal if untreated, patients who respond well to therapy have an excellent prognosis. Nevertheless, second-line treatment is necessary in approximately 20% of patients, due to either intolerance or insufficient response to first line treatment.While data for mycophenolate mofetil (MMF) in patients intolerant to azathioprine is encouraging, MMF seems of less benefit in patients with insufficient response to first line treatment, but analyzed data on this issue is limited. Aim: To evaluate the efficacy and safety of MMF as a second-line therapy in patients with AIH. Methods: Retrospective analysis of a monocentric database of AIH patients who received medical care from 2000 to 2022. Clinical, immunological and biochemical parameters were assessed at different time points including last follow-up. Results: Overall, 144 patients with AIH were identified. Fifty out of 144 (35%) AIH patients received MMF. Forty (80%) received MMF due to first line treatment intolerance, while ten (20%) due to insufficient response to first line treatment.Remission with MMF monotherapy was 81.5% in the intolerance group versus 30% in the insufficient response group. Patients switched to MMF because of an insufficient response, more often needed additional prednisolone doses higher than 5 mg/day, a switch to third-line treatment or combination regiments, to achieve disease control. Conclusions: Patients treated with MMF because of intolerance to first line treatment show a good disease control under MMF in the majority of cases. Efficacy is considerably lower in the patients switched to MMF because of an insufficient response to first line treatment

A series of Fas receptor agonist antibodies that demonstrate an inverse correlation between affinity and potency

Receptor agonism remains poorly understood at the molecular and mechanistic level. In this study, we identified a fully human anti-Fas antibody that could efficiently trigger apoptosis and therefore function as a potent agonist. Protein engineering and crystallography were used to mechanistically understand the agonistic activity of the antibody. The crystal structure of the complex was determined at 1.9 Å resolution and provided insights into epitope recognition and comparisons with the natural ligand FasL (Fas ligand). When we affinity-matured the agonist antibody, we observed that, surprisingly, the higher-affinity antibodies demonstrated a significant reduction, rather than an increase, in agonist activity at the Fas receptor. We propose and experimentally demonstrate a model to explain this non-intuitive impact of affinity on agonist antibody signalling and explore the implications for the discovery of therapeutic agonists in general

Study design for development of novel safety biomarkers of drug-induced liver injury by the translational safety biomarker pipeline (TransBioLine) consortium: a study protocol for a nested case–control study

A lack of biomarkers that detect drug-induced liver injury (DILI) accurately continues to hinder early- and late-stage drug development and remains a challenge in clinical practice. The Innovative Medicines Initiative’s TransBioLine consortium comprising academic and industry partners is developing a prospective repository of deeply phenotyped cases and controls with biological samples during liver injury progression to facilitate biomarker discovery, evaluation, validation and qualification.In a nested case–control design, patients who meet one of these criteria, alanine transaminase (ALT) ≥ 5 × the upper limit of normal (ULN), alkaline phosphatase ≥ 2 × ULN or ALT ≥ 3 ULN with total bilirubin > 2 × ULN, are enrolled. After completed clinical investigations, Roussel Uclaf Causality Assessment and expert panel review are used to adjudicate episodes as DILI or alternative liver diseases (acute non-DILI controls). Two blood samples are taken: at recruitment and follow-up. Sample size is as follows: 300 cases of DILI and 130 acute non-DILI controls. Additional cross-sectional cohorts (1 visit) are as follows: Healthy volunteers (n = 120), controls with chronic alcohol-related or non-alcoholic fatty liver disease (n = 100 each) and patients with psoriasis or rheumatoid arthritis (n = 100, 50 treated with methotrexate) are enrolled. Candidate biomarkers prioritised for evaluation include osteopontin, glutamate dehydrogenase, cytokeratin-18 (full length and caspase cleaved), macrophage-colony-stimulating factor 1 receptor and high mobility group protein B1 as well as bile acids, sphingolipids and microRNAs. The TransBioLine project is enabling biomarker discovery and validation that could improve detection, diagnostic accuracy and prognostication of DILI in premarketing clinical trials and for clinical healthcare application

The LRRK2 signalling system

The LRRK2 gene is a major contributor to genetic risk for Parkinson's disease and understanding the biology of the leucine-rich repeat kinase 2 (LRRK2, the protein product of this gene) is an important goal in Parkinson's research. LRRK2 is a multi-domain, multi-activity enzyme and has been implicated in a wide range of signalling events within the cell. Because of the complexities of the signal transduction pathways in which LRRK2 is involved, it has been challenging to generate a clear idea as to how mutations and disease associated variants in this gene are altered in disease. Understanding the events in which LRRK2 is involved at a systems level is therefore critical to fully understand the biology and pathobiology of this protein and is the subject of this review

Study design for development of novel safety biomarkers of drug-induced liver injury by the translational safety biomarker pipeline (TransBioLine) consortium: a study protocol for a nested case–control study

A lack of biomarkers that detect drug-induced liver injury (DILI) accurately continues to hinder early- and late-stage drug development and remains a challenge in clinical practice. The Innovative Medicines Initiative’s TransBioLine consortium comprising academic and industry partners is developing a prospective repository of deeply phenotyped cases and controls with biological samples during liver injury progression to facilitate biomarker discovery, evaluation, validation and qualification. In a nested case–control design, patients who meet one of these criteria, alanine transaminase (ALT) ≥ 5 × the upper limit of normal (ULN), alkaline phosphatase ≥ 2 × ULN or ALT ≥ 3 ULN with total bilirubin > 2 × ULN, are enrolled. After completed clinical investigations, Roussel Uclaf Causality Assessment and expert panel review are used to adjudicate episodes as DILI or alternative liver diseases (acute non-DILI controls). Two blood samples are taken: at recruitment and follow-up. Sample size is as follows: 300 cases of DILI and 130 acute non-DILI controls. Additional cross-sectional cohorts (1 visit) are as follows: Healthy volunteers (n = 120), controls with chronic alcohol-related or non-alcoholic fatty liver disease (n = 100 each) and patients with psoriasis or rheumatoid arthritis (n = 100, 50 treated with methotrexate) are enrolled. Candidate biomarkers prioritised for evaluation include osteopontin, glutamate dehydrogenase, cytokeratin-18 (full length and caspase cleaved), macrophage-colony-stimulating factor 1 receptor and high mobility group protein B1 as well as bile acids, sphingolipids and microRNAs. The TransBioLine project is enabling biomarker discovery and validation that could improve detection, diagnostic accuracy and prognostication of DILI in premarketing clinical trials and for clinical healthcare application

Adipopenia correlates with higher portal pressure in patients with cirrhosis.

BACKGROUND & AIMS In cirrhosis, hepatic venous pressure gradient (HVPG) and imaging body composition assessment can influence prognosis. We assessed whether adipose and skeletal muscle tissue reflect the severity of portal hypertension (PH), and whether they improve non-invasive prediction of decompensation and death. METHODS We included 84 cirrhosis patients with HVPG and computed tomography (CT) within 12 weeks of HVPG at a single centre. L3 vertebra CT images were used for body composition indexes (cm /m ): total adipose tissue index (TATI), visceral adipose tissue index (VATI), subcutaneous adipose tissue index (SATI), intramuscular adipose tissue index (IMATI), skeletal muscle index (SMI) and psoas muscle index (PMI). Correlations were calculated between indexes, HVPG and standard non-invasive tests for PH. 12-month decompensation and death predictors were determined. RESULTS Male 61%; BMI 28±5 kg/m ; alcoholic liver disease in 51%, non-alcoholic steatohepatitis in 24%; HVPG 14±6 mmHg; 45% compensated. Median follow-up was 11 (4-17) months. HVPG correlated with SATI (r=-0.282,p=0.01), TATI (r=-0.220,p=0.045) and SATI/VATI index (r =-0.240,p=0.03). In compensated patients, lower VATI (HR 0.94 (0.90-0.99), p=0.01) was associated with 12-month decompensation. Combining TATI and liver stiffnessxspleen size over-platelet count risk score (LSPS) added discriminative capacity for 12-month decompensation (AUROC 0.91 vs. 0.87). IMATI was independently associated with mortality in decompensated patients. MELD-Na combined with IMATI discriminated excellently for mortality (AUROC 0.94; p<0.001). CONCLUSIONS HVPG inversely correlates with imaging markers of adipose tissue, while markers of sarcopenia were unrelated to PH. In compensated patients, TATI improves non-invasive prediction of decompensation. In decompensated patients, IMATI independently predicted mortality. This article is protected by copyright. All rights reserved