Growing Human Livers: Current Progress (Mid- 2025) and Future Potential
Scientists are making remarkable progress toward
growing functional human livers using bioengineering techniques that share
similarities with cloning approaches. While we're not quite at full-scale liver
production yet, the field has achieved several groundbreaking milestones that
suggest this goal is achievable.
Current Achievements
Miniature Functional Livers
Researchers have successfully created miniature
human livers that function like natural organs. Teams at Wake Forest
University have engineered livers about an inch in diameter that weigh 0.2
ounces, demonstrating that human liver cells can be used to generate
functioning liver tissue. These mini-livers secrete bile acids and urea
just like normal livers.
Japanese scientists have made particularly impressive
advances by creating 4-millimeter "liver buds" from human stem cells
that, when transplanted into mice, work in conjunction with the animals' organs
and produce human liver-specific proteins. This represents the
first time people have made a solid organ using pluripotent stem cells.
Multiple Bioengineering Approaches
Scientists are pursuing several promising methods:
- Decellularization:
Researchers take animal livers, remove all cells with mild detergent,
leaving only the collagen "skeleton," then repopulate it with
human liver cells
- Stem
cell conversion: Converting human skin cells into stem cells, then
coaxing them to become liver cells
- 3D
bioprinting: Using advanced printing techniques to create liver
scaffolds
- Organoid
development: Growing "mini-organs" from stem cells that can
repair damaged liver tissue
Breakthrough Human Trials
The field has reached a significant milestone with the
first human trial beginning in 2024. A volunteer with severe liver
disease received an experimental treatment designed to grow a second "mini
liver" in their lymph node. This approach injects healthy liver cells
into lymph nodes, where they can develop into functional liver tissue while
some cells migrate to help regenerate the existing damaged liver.
Current Limitations and Challenges
Scale Requirements
While current mini-livers are functional, they need
significant scaling up. An adult human liver weighs about 4.4 pounds, but
researchers estimate that an engineered liver would need to weigh about one
pound to sustain human life, since livers functioning at 30% capacity can
support the body.
Technical Hurdles
Key challenges that researchers are actively addressing
include:
- Cell
production: Learning to grow billions of liver cells simultaneously
- Vascularization:
Creating proper blood vessel networks within the engineered tissue
- Bile
duct construction: Developing fully functional bile drainage systems
- Long-term
functionality: Ensuring engineered livers maintain function over time
Future Timeline and Prospects
The research suggests that patient-specific liver
substitutes are achievable through continued optimization and
integration of induced pluripotent stem cells. However, scientists
emphasize they're still at an early stage, with many technical hurdles
requiring resolution before patient treatment becomes routine.
Bioengineered liver tissues currently need "additional
rounds of molecular fine tuning before they can be tested in clinical
trials", but the rapid advancement in recent years suggests this
technology could become clinically viable within the next decade.
Beyond Transplantation
Engineered livers offer additional benefits beyond treating
liver disease. They provide platforms for drug safety testing that
more closely mimic human liver metabolism compared to animal models, and can
serve as disease models for research purposes.
The field of liver bioengineering is advancing rapidly, with multiple successful approaches demonstrating that growing functional human livers is not just theoretically possible but actively being achieved in laboratories worldwide. While full-scale clinical implementation still requires overcoming significant technical challenges, the foundation has been established for what could become a revolutionary treatment for liver disease.
Created with Perplexity
Sources:
The Conversation - How to grow human mini-livers in the lab to help solve liver disease
https://theconversation.com/how-to-grow-human-mini-livers-in-the-lab-to-help-solve-liver-disease-121297
Wake Forest University School of Medicine - Human Liver
https://school.wakehealth.edu/research/institutes-and-centers/wake-forest-institute-for-regenerative-medicine/research/replacement-organs-and-tissue/human-liver
New Atlas - Researchers grow laboratory-engineered miniature human livers
https://newatlas.com/bioengineered-miniature-human-livers/16790/
UPMC - Lab-Grown Miniature Human Livers Transplanted into Rats
https://www.upmc.com/media/news/052820-lab-grown-miniature-human-livers
CBS News - Researchers create miniature human liver out of stem cells
https://www.cbsnews.com/news/researchers-create-miniature-human-liver-out-of-stem-cells/
National Library of Medicine: Liver Bioengineering: Promise, Pitfalls, and Hurdles to Overcome
https://pubmed.ncbi.nlm.nih.gov/31289714/
University of Cambridge - Lab-grown ‘mini-bile ducts’ used to repair human livers in regenerative medicine first
https://www.cam.ac.uk/research/news/lab-grown-mini-bile-ducts-used-to-repair-human-livers-in-regenerative-medicine-first
MIT Technology Review - This company is about to grow new organs in a person for the first time
https://www.technologyreview.com/2022/08/25/1058652/grow-new-organs/
Springer Nature - ‘Mini liver’ will grow in person’s own lymph node in bold new trial
https://www.nature.com/articles/d41586-024-00975-z