Three-dimensional multicellular human liver model: For the first time, a 3D human organoid model, developed with liver tissue from patients, consists of three liver cell types, derived from adult hepatocytes, cholangiocytes, and liver mesenchymal cells.
Retaining structure and function: The novel complex organoid models, or assembloids, reconstruct essential structural and functional features of the human periportal liver region and have patient-specific traits. They capture key aspects of human liver physiology in a dish, including drug detoxification and metabolism.
Liver disease investigation: When manipulated, this human periportal liver model can mimic several characteristics of biliary fibrosis. It provides a platform to study liver diseases in humans, accelerate the development of new drugs, enable early diagnosis, and advance personalized medicine.
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Liver disease is a major global health problem, causing over two million deaths worldwide each year. While animal models have helped to understand liver biology, they often fail to accurately translate to human biology. Due to the liver’s unique architecture, existing human models fail to replicate the complex interactions between different cell types in the liver and accurately show how diseases progress. Existing tissue-derived liver organoid models consist of only one cell type and fail to replicate the complex cellular composition and tissue architecture, such as the liver periportal region. Complex 3D multicellular models that capture human liver portal cellular interactions do not exist for adult human liver tissue yet. This limits the ability to study liver disease and develop new treatments.
Previous liver models
The research group of Meritxell Huch, director at the Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG) in Dresden, Germany, started to address this issue in a previous study in 2021 (Dynamic cell contacts between periportal mesenchyme and ductal epithelium act as a rheostat for liver cell proliferation, Cordero-Espinoza, Lucía et al., Cell Stem Cell, Volume 28, Issue 11), where the researchers developed a liver organoid consisting of two cell types, cholangiocyte and mesenchyme cells, but still lacked other periportal cell types – most importantly hepatocytes, the cells that build the majority of liver mass. In 2025, the research group of Meritxell Huch was able to create a next-generation organoid model, composed of three liver cell types of the mouse – adult hepatocytes, cholangiocytes, and liver mesenchymal cells – to reconstruct the mouse liver periportal region. (Mouse periportal liver assembloids recapitulate mesoscale hepatic architecture and biliary fibrosis, 29th May 2025, Nature)
Developing a multicellular human liver model
In the recent study, published in the journal Nature, researchers from the group of Meritxell Huch, together with colleagues from the group of Andrej Shevchenko at the MPI-CBG, from the group of Daniel Stange at the Carl Gustav Carus University Hospital (UKD) Dresden and the National Center for Tumor Diseases (NCT/UCC), and from the groups of Daniel Seehofer and Georg Damm at the Clinic for Visceral, Transplant, Thoracic, and Vascular Surgery at the Leipzig University Medical Center, developed a patient-specific human periportal liver assembloid. This advanced liver model features adult human cholangiocytes, liver mesenchymal cells, and hepatocytes, which were derived from 28 patients. It contains multiple cells, which are combined together in a process similar to LEGO. Once assembled, the cells self-organize into 3D structures that reproduce in vitro the cellular arrangements and cell-cell interactions of the tissue in vivo.
Developing the liver model was real teamwork. It involved not only the experimental scientists from the Huch lab and clinicians from Leipzig and Dresden but also bioinformaticians and technical assistants from the different labs. One of the four lead authors, Yohan Kim, a former postdoctoral researcher in the Huch group and now an assistant professor at Sungkyunkwan University in Suwon, South Korea, says, “When we received the tissue from the patients, we first had to separate the individual cell types and expand them in a dish before combining them again. I researched the culture conditions for the cells to grow before being assembled, prior to my departure for my new position at Sungkyunkwan University.” The tissue from the patients was provided by the Carl Gustav Carus University Hospital (UKD) in Dresden and the Clinic for Visceral, Transplant, Thoracic, and Vascular Surgery at the Leipzig University Medical Center. With the support of the research technician Robert Arnes-Benito, the culture conditions were further optimized into what are now the final culture conditions to expand human hepatocytes.
Sagarika Dawka, a doctoral student and another lead author of the study, continued the work of Yohan by finding conditions to mature the cells in vitro. She says, “I was able to develop the liver model further, so it featured bile canaliculi, which drain into the bile duct in the liver periportal region. When this bile drainage system is disrupted, it causes liver damage and disease. This is why it was so important for our liver models to include bile canaliculi. The present study is the first complex human liver model outside of the body that has bile canaliculi.”
Lei Yuan, a postdoctoral researcher and one of the lead authors, then worked on combining the cells to make the periportal assembloids. First, he labeled the different cells (liver mesenchymal cells and cholangiocytes) in order to be able to track them once combined. Then, he found the right conditions to induce their self-assembly. “Additionally, I optimized the periportal assembloid protocol from the assembly method to the media that the cells were growing in. The proper medium is essential for promoting the cells' growth and differentiation,” says Lei.
Another lead author of the study, Anke Liebert, a postdoctoral researcher, was mainly responsible for the molecular and functional characterization of the liver models. “I was looking at how well the models were performing their function. I tested how well our liver models function compared to normal human liver cells. With the help of computational biologist Fabian Rost, I tested that the models correctly captured the gene expression of the living tissue.” With their existing liver models, the group created a living biobank of hepatocyte organoids from 28 patients, which can be frozen and thawed to reinitiate cultures when needed.
Personalized medicine and drug development
The novel human liver model shows patient-specific traits and retains essential structural and functional features of the human periportal liver region. “We overcame a major challenge with our new model. Reconstructing the multicellular periportal liver tissue organization and cellular interactions outside of the living body hasn’t been possible so far. With our models, we can build and control different parts of the liver in a lab. This helps us understand how different cells and their surroundings work together to create a healthy liver, and, when these interactions are wrong, how diseases like biliary fibrosis arise,” says Meritxell Huch, who oversaw and supervised the study. “Our new liver models have the potential to change the way we study and treat liver diseases. They could help us develop new diagnostic tests, test the safety of new medicines, improve drug toxicity assessment, and create personalized treatments for patients with liver diseases.”
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