New insights into liver injury and regeneration from single-cell transcriptomics

Recent advancements in single-cell transcriptomics have significantly enhanced our understanding of acute liver injury (ALI) and regeneration. These technologies enable high-resolution profiling of individual cells, uncovering the diverse and dynamic responses of liver cells to injury. By integrating single-cell RNA sequencing (scRNA-seq) with spatial transcriptomics, researchers have elucidated the complex cellular and molecular mechanisms driving ALI and regeneration processes. This review summarises the platforms and analytical methods of single-cell transcriptomics in liver research and discusses liver sample processing considerations for scRNA-seq, including the comparison between in vivo enzymatic perfusion and ex vivo digestion. It highlights the transformative impact of single-cell transcriptomics on ALI and regeneration studies, revealing novel insights into previously unrecognised cell subpopulations. Key discoveries include the identification of fetal-like and Anxa2⁺ migratory hepatocytes at injury-repair interfaces, the characterisation of distinct activated hepatic stellate cell states during injury and repair phases, and the elucidation of zone-specific endothelial cell responses in Wnt signalling. Notable findings in macrophage heterogeneity include the discovery of Trem2⁺ populations in both Kupffer cells and monocyte-derived macrophages, with distinct roles in injury and repair processes. The application of single-cell transcriptomics continues to hold promise for identifying novel therapeutic targets, ultimately advancing the development of novel treatment strategies for acute liver diseases.