Hong Li

The liver possesses a remarkable regenerative capacity following injury, a process fundamentally orchestrated by the dynamic extracellular matrix (ECM). Far beyond a passive scaffold, the liver matrisome functions as an integrative mechano-biochemical circuit. It comprises a core structural network together with regulatory non-core components that collectively establish a dynamic niche. This niche stores and releases mitogenic cues, transmits mechanical forces, and coordinates multicellular crosstalk. Through receptors like integrins and mechanosensitive channels, ECM-derived signals converge on key pathways, including Hippo-YAP/TAZ and Wnt/β-catenin, to drive hepatocyte proliferation and tissue restructuring. The balance between matrix stabilization and remodeling dictates the outcome, guiding physiological regeneration versus fibrotic progression. Consequently, the ECM emerges as a central therapeutic target and a blueprint for engineering strategies aimed at restoring liver function. Strategies to recalibrate its composition, mechanics, and remodeling, from pharmacological inhibitors to bioengineered decellularized ECM scaffolds, hold significant potential for steering liver repair and combating chronic liver disease.

The liver possesses a remarkable regenerative capacity following injury, a process fundamentally orchestrated by the dynamic extracellular matrix (ECM). Far beyond a passive scaffold, the liver matrisome functions as an integrative mechano-biochemical circuit. It comprises a core structural network and regulatory non-core components that together establish a dynamic niche. This niche stores and releases mitogenic cues, transmits mechanical forces, and coordinates multicellular crosstalk. Through receptors like integrins and mechanosensitive channels, ECM-derived signals converge on key pathways, including Hippo-YAP/TAZ and Wnt/β-catenin, to drive hepatocyte proliferation and tissue restructuring. The balance between matrix stabilization and remodeling dictates the outcome, guiding physiological regeneration versus fibrotic progression. Consequently, the ECM emerges as a central therapeutic target and a blueprint for engineering strategies aimed at restoring liver function. Strategies to recalibrate its composition, mechanics, and remodeling, from pharmacological inhibitors to bioengineered decellularized ECM scaffolds, hold transformative potential for steering liver repair and combating chronic disease.

Background: Lysyl oxidase (LOX) family members (LOX and LOXL1 to 4) are crucial copper-dependent enzymes responsible for cross-linking collagen and elastin. Previous studies have revealed that LOX and LOXL1 are the most dramatically dysregulated LOX isoforms during liver fibrosis. However, the crosstalk between them and the underlying mechanisms involved in the profibrotic behaviors of HSCs, as well as the progression of liver fibrosis, remain unclear. Methods: pCol9GFP-HS4,5^Tg mice, Loxl1 ^fl/fl Gfap ^Cre mice, human HSC line, and primary HSCs were enrolled to study the dysregulation pattern, profibrotic roles, and the potential mechanisms of LOX and LOXL1 interaction involved in the myofibroblast-like transition of HSCs and liver fibrogenesis. Results: LOX and LOXL1 were synergistically upregulated during liver fibrogenesis, irrespective of etiology, together orchestrating the profibrotic behaviors of HSCs. LOX and LOXL1 coregulated in HSCs, whereas LOXL1 dominated in the coregulation loop. Interestingly, the interaction between LOXL1 and LOX prolonged their half-lives, specifically enhancing the Notch signal-mediated myofibroblast-like transition of HSCs. Selective disruption of Loxl1 in Gfap ⁺ HSCs deactivated the Notch signal, inhibited HSC activation, and relieved carbon tetrachloride-induced liver fibrosis. Conclusions: Our current study confirmed the synergistic roles and the underlying mechanisms of LOXL1 and LOX crosstalk in the profibrotic behaviors of HSCs and liver fibrosis progression, providing experimental evidence for further clear mechanism-based anti-LOXL1 strategy development in the therapy of liver fibrosis.

Background: HBV-specific T lymphocytes are pivotal in eliminating the hepatitis B virus (HBV) and regulating intrahepatic inflammatory reactions. Effective T cell responses curtail HBV infection; however, compromised immunity can result in persistent infection. Beyond the acute phase, the continued presence of antigens and inflammation leads to the increased expression of various inhibitory receptors, such as PD-1, CTLA-4, Tim-3, LAG3, 2B4, CD160, BTLA, and TIGIT. This escalates the dysfunction of and diminishes the immune and proliferative abilities of T cells. Methods: In this study, we reviewed English-language literature from PubMed, Web of Science, and Scopus up to 9 July 2023. This paper aims to elucidate the inhibitory effects of these receptors on HBV-specific T lymphocytes and how immune function can be rejuvenated by obstructing the inhibitory receptor signaling pathway in chronic HBV patients. We also summarize the latest insights into related anti-HBV immunotherapy. Result: From 66 reviewed reports, we deduced that immunotherapy targeting inhibitory receptors on T cells is a reliable method to rejuvenate T cell immune responses in chronic HBV patients. However, comprehensive combination therapy strategies are essential for a functional cure. Conclusions: Targeting T cell suppressor receptors and combining immunotherapy with antiviral treatments may offer a promising approach towards achieving a functional cure, urging future research to prioritize effective combination therapeutic strategies for chronic HBV infection.