Integrating Spatial Transcriptomics and Single-Cell RNA-seq Reveals the Gene Expression Profling of the Human Embryonic Liver

The liver is one of vital organs of the human body, and it plays an important role in the metabolism and detoxification. Moreover, fetal liver is one of the hematopoietic places during ontogeny. Understanding how this complex organ develops during embryogenesis will yield insights into how functional liver replacement tissue can be engineered and how liver regeneration can be promoted. Here, we combine the advantages of single-cell RNA sequencing and Spatial Transcriptomics (ST) technology for unbiased analysis of fetal livers over developmental time from 8 post-conception weeks (PCW) and 17 PCW in humans. We systematically identified nine cell types, and defined the developmental pathways of the major cell types. The results showed that human fetal livers experienced blood rapid growth and immigration during the period studied in our experiments, and identified the differentially expressed genes, and metabolic changes in the developmental process of erythroid cells. In addition, we focus on the expression of liver disease related genes, and found that 17 genes published and linked to liver disease mainly expressed in megakaryocyte and endothelial, hardly expressed in any other cell types. Together, our findings provide a comprehensive and clear understanding of the differentiation processes of all main cell types in the human fetal livers, which may provide reference data and information for liver disease treatment and liver regeneration.

Liver and biliary diseases in infancy and childhood

Most liver diseases that occur in adults also occur in children, but some present almost exclusively in early childhood. Neonatal jaundice is common and usually short-lived. Onset before 24 h, or continuation beyond 2 weeks, strongly suggests an underlying pathology, when biliary atresia is the most common cause, with liver transplantation allowing some patients to survive to adolescence and adulthood. Some genetic causes of cholestasis (e.g. MDR3 deficiency) can present in adults. A long list of metabolic disorders present with evidence of liver involvement, with later manifesting diseases including those with accumulation of material in the liver. Liver transplantation is an excellent treatment for many of these disorders, and a growing number of metabolic disorders that do not cause liver disease per se are now being successfully managed through liver replacement, with patients surviving into adult life.

Timing of transjugular intrahepatic portosystemic stent-shunt in Budd–Chiari syndrome: A UK hepatologist's perspective

Budd–Chiari syndrome (BCS) is a rare but fatal disease caused by the obstruction in hepatic venous outflow tract (usually by thrombosis) and is further classified into two subtypes depending on the level of obstruction. Patients with BCS often have a combination of prothrombotic risk factors. Clinical presentation is diverse. Stepwise management strategy has been suggested with excellent 5-year survival rate. It includes anticoagulation, treatment of identified prothrombotic risk factor, percutaneous recanalization, and transjugular intrahepatic portosystemic shunt (TIPS) to reestablish hepatic venous outflow and liver transplantation in unresponsive patients. Owing to the rarity of BCS, there are no randomized controlled trials (RCTs) precisely identifying the timing for TIPS. TIPS should be considered in patients with refractory ascites, variceal bleed, and fulminant liver failure. Liver replacement is indicated in patients with progressive liver failure and in those in whom TIPS is not technically possible. The long-term outcome is usually influenced by the underlying hematologic condition and the development of hepatocellular carcinoma. This review focuses on the timing and the long-term efficacy of TIPS in patients with BCS.

Cell-based liver therapies: past, present and future

Liver transplantation represents the standard treatment for people with an end-stage liver disease and some liver-based metabolic disorders; however, shortage of liver donor tissues limits its availability. Furthermore, whole liver replacement eliminates the possibility of using native liver as a possible target for future gene therapy in case of liver-based metabolic defects. Cell therapy has emerged as a potential alternative, as cells can provide the hepatic functions and engraft in the liver parenchyma. Various options have been proposed, including human or other species hepatocytes, hepatocyte-like cells derived from stem cells or more futuristic alternatives, such as combination therapies with different cell types, organoids and cell–biomaterial combinations. In this review, we aim to give an overview of the cell therapies developed so far, highlighting preclinical and/or clinical achievements as well as the limitations that need to be overcome to make them fully effective and safe for clinical applications. This article is part of the theme issue ‘Designer human tissue: coming to a lab near you’.