Cellular and molecular heterogeneity in the liver has been increasingly recognized to drive liver fibrosis progression, but the particular events that occur initially in response to liver injury and trigger immune cell recruitment remain unclear. Here, we identify epigenetically aberrant liver sinusoidal endothelial cells (LSECs) as key players in this process. Mechanistically, the epigenetic readers like bromodomain-containing protein 4–dependent (BRD4-dependent) super enhancers (SEs) activate proinflammatory genes, including promyelocytic leukemia (PML). The PML protein, in turn, binds BRD4 and amplifies proinflammatory angiocrine signaling through phase separation–dependent SE activation via PML/BRD4 condensate formation. In mouse models, LSEC-specific depletion of the PML/BRD4 complex mitigates liver inflammation and fibrosis. Single-cell RNA-seq reveals that epigenetically aberrant LSECs exhibit a reprogrammed proinflammatory angiocrine landscape in mouse fibrotic livers. TIMP1 + LSECs promote the recruitment of CD63 + monocyte–derived macrophages (MoMFs) during liver fibrosis progression. Thereby, PML/BRD4 in LSECs governs inflammatory immune cell recruitment in liver fibrosis. Pharmacological BRD4 inhibition or epigenetic PML-SE repression alleviates liver inflammation and fibrosis. In conclusion, PML/BRD4-mediated SE activation via phase separation drives proinflammatory angiocrine signaling in LSECs, initiating the inflammatory cascade and subsequent immune cell recruitment during liver fibrosis.
Use of non‐invasive diagnostic tools for metabolic dysfunction‐associated steatohepatitis: A qualitative exploration of challenges and barriers
Abstract Background and Aims Non‐invasive tests (NITs) are underutilized for diagnosis and risk stratification in metabolic dysfunction‐associated steatotic liver disease (MASLD), despite good accuracy. This study aimed to identify challenges and barriers to the use of NITs in clinical practice. Methods We conducted a qualitative exploratory study in Germany, Italy, United Kingdom and United States. Phase 1 participants (primary care physicians, hepatologists, diabetologists, researchers, healthcare administrators, payers and patient advocates; n = 29) were interviewed. Phase 2 participants (experts in MASLD; n = 8) took part in a group discussion to validate and expand on Phase 1 findings. Finally, we triangulated perspectives in a hybrid deductive/inductive thematic analysis. Results Four themes hindering the use of NITs emerged: (1) limited knowledge and awareness; (2) unclear referral pathways for patients affected by liver conditions; (3) uncertainty over the value of NITs in monitoring and managing liver diseases; and (4) challenges justifying system‐level reimbursement. Through these themes, participants perceived a stigma associated with liver diseases, and primary care physicians generally lacked awareness, adequate knowledge and skills to use recommended NITs. We identified uncertainties over the results of NITs, specifically to guide lifestyle intervention or to identify patients that should be referred to a specialist. Participants indicated an ongoing need for research and development to improve the prognostic value of NITs and communicating their cost‐effectiveness to payers. Conclusions This qualitative study suggests that use of NITs for MASLD is limited due to several individual and system‐level barriers. Multi‐level interventions are likely required to address these barriers.
Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)
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When Is a Critically Ill Cirrhotic Patient Too Sick to Transplant? Development of Consensus Criteria by a Multidisciplinary Panel of 35 International Experts
Background. Critically ill cirrhotic patients are increasingly transplanted, but there is no consensus about futile liver transplantation (LT). Therefore, the decision to delay or deny LT is often extensively debated. These debates arise from different opinions of futility among transplant team members. This study aims to achieve a multinational and multidisciplinary consensus on the definition of futility in LT and to develop well-articulated criteria for not proceeding with LT due to futility. Methods. Thirty-five international experts from anesthesiology/intensive care, hepatology, and transplant surgery were surveyed using the Delphi method. More than 70% of similar answers to a question were necessary to define agreement. Results. The panel recommended patient and graft survival at 1 year after LT to define futility. Severe frailty and persistent fever or <72 hours of appropriate antimicrobial therapy in case of ongoing sepsis were considered reasons to delay LT. A simple assessment of the number of organs failing was considered the most appropriate way to decide whether LT should be delayed or denied, with respiratory, circulatory and metabolic failures having the most influence in this decision. The thresholds of severity of organ failures contraindicating LT for which a consensus was achieved were a Pa o 2 /FiO2 ratio<150 mm Hg, a norepinephrine dose >1 μg/kg per minute and a serum lactate level >9 mmol/L. Conclusions. Our expert panel provides a consensus on the definition of futile LT and on specific criteria for postponing or denying LT. A framework that may facilitate the decision if a patient is too sick for transplant is presented.