Growing Human Livers: Current Progress (2025)

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

My problem with fake sugar

Sorbitol: Ingesting large amounts of sorbitol can lead to some abdominal pain, gas, and mild to severe diarrhea. Sorbitol ingestion of 20 grams/day (g/d) as sugar-free gum has led to severe diarrhea leading to unintended weight loss of 24 lbs in a 114 lb woman; another patient required hospitalization after habitually consuming 30g/d.[7] Sorbitol can also aggravate irritable bowel syndrome and fructose malabsorption.

If it does bad in large amounts, do I even want to eat a little of it? No, I don't.

Splenda/Sucralose:

Migraine headaches

After FDA approval, a study published in the Journal of Head and Face Pain reported sucralose as a possible trigger for migraine patients.[19] Another study published in the Journal of Mutation Research linked high doses (2 g per kg; equal to 10,000 packets per day for the 150 lb person in the above example) of sucralose to DNA damage in mice.[20]

[edit] Thymus

Concerns have been raised about the effect of sucralose on the thymus, an organ that is important to the immune system. A report from NICNAS cites two studies on rats, both of which found "a significant decrease in mean thymus weight" at a certain dose.[21] The sucralose dosages which caused the thymus gland effects referenced in the NICNAS report was 3000 mg/kg bw/day for 28 days. For an 80 kg (176 lb) human, this would mean a 28-day intake of 240 grams of sucralose, which is equivalent to more than 20,000 individual Splenda packets/day for approximately one month. The dose required to provoke any immunological response was 750 mg/kg bw/day,[22] or 60 grams of sucralose per day, which is more than 5,000 Splenda packets/day (there are 11.9 mg of sucralose in a 1g retail packet of Splenda). These and other studies were considered by regulators before concluding that sucralose was safe. However, because some ingested sucralose is broken down and absorbed by the body there is concern that chronic consumption may lead to thymus shrinkage or other side-effects.

[edit] Gastrointestinal tract

The bulk of sucralose ingested does not leave the gastrointestinal tract and is directly excreted in the feces while 11-27% of it is absorbed.[2] The amount that is absorbed from the GI tract is largely removed from the blood stream by the kidneys and excreted in the urine with 20-30% of the absorbed sucralose being metabolized.[2] According to one study, sucralose is digestible by a number of microorganisms and is broken down once released into the environment.[23] However, measurements by the Swedish Environmental Research Institute have shown that wastewater treatment has little effect on sucralose, which is present in wastewater effluents at levels of several μg/l. [24]There are no known eco-toxicological effects at such levels, but the Swedish Environmental Protection Agency warns that there may be a continuous increase in levels if the compound is only slowly degraded in nature.[25] Additional research has shown the potential for DNA damage in gastrointestinal organs of laboratory mice.[26]

[edit] Organochlorides

The basis for concern about the safety of sucralose derives from the class of chemical to which it belongs. The sucralose molecule is an organochloride (or chlorocarbon). Since some organochlorides are known to cause adverse health effects in extremely small concentrations, critics of sucralose feel the extra-high burden of proof is warranted. Although some chlorocarbons are toxic, sucralose is not known to be toxic in small quantities and is extremely insoluble in fat; it can not accumulate in fat like chlorinated hydrocarbons. In addition, sucralose does not break down or dechlorinate.[27]

In contrast to these concerns, many organochlorides occur naturally in food sources such as seaweed.[28]

[edit] Weight gain

Research where rats were given yogurt sweetened with either sugar or saccharin found that the rats given saccharin gained more weight, because they ate more afterwards, presumably due to compensatory effects. It is hypothesized that this effect would apply to all non-nutritive sweeteners, and would also be seen in humans. [29]

[edit] Allergic reactions

There have been anecdotal reports of "allergic" reactions and other adverse reactions to Splenda. [30][31]

High-fructose corn syrup:
Check out the wiki. I eat this stuff, but as little as possible.

All these are from Wikipedia. I'm not making this up.