Medical Network August 30th Scientists from the University of Edinburgh Medical Research Council (MRC) Regenerative Medicine Center combined with stem cell technology and 3D printing technology, successfully cultivated human 3D liver tissue and showed therapeutic potential at the mouse level.
Scientists say that in addition to early exploration for the development of human liver tissue implants, the study can also reduce the need for animal research by building platforms to study the effects of human liver disease and test drugs in the laboratory.
In a study published in the Archives of Toxicology, scientists collected human embryonic stem cells and induced the formation of pluripotent stem cells (adult cells that have been induced to transform into stem cells), which are formed into hepatocytes by directed induction.
Professor David Hay of the MRC Center for Regenerative Medicine at the University of Edinburgh, who is in charge of the study, said: "This is the first time in history that stem cells derived from stem cells have been cultured in vitro for more than a year. The cells survive and stabilize for a long time. It is very difficult, but it is essential for use in the human body."
Scientists then worked with materials chemists and engineers to identify suitable polymers that have been approved for use in the human body in order to develop them into 3-D scaffolds. The best material is the biodegradable polyester polycaprolactone, which is made into microscopic fibers that form a one-centimeter square, millimeter-thick stent. Thereafter, hepatocytes derived from embryonic stem cells, which have been grown in culture for 20 days, were loaded onto the scaffold and implanted subcutaneously in the mouse.
The results of the study showed that the blood vessels were able to grow successfully on the stent. In addition, the authors also found that the mouse's blood contains human liver protein, indicating that the tissue has successfully integrated with the circulatory system and that the scaffold is not rejected by the animal's immune system.
Further, the authors tested the effects of liver tissue scaffolds in mice with tyrosinemia. Tyrosinemia is a potentially fatal genetic disease in which the enzyme that breaks down amino acid tyrosine in the liver is defective, leading to the accumulation of toxic metabolites.
Studies have shown that implanted liver tissue can help tyrosine in mice that are tyrosinemia. Compared to the mice in the control group receiving the empty scaffold, mice transplanted with 3D printed liver tissue lost weight, accumulated less toxins in the blood, and showed less signs of liver damage.
Professor Hay said: "I hope that one day such an implant may one day help people with liver failure. Putting the stent under the skin has a huge advantage over the insertion of tissue graft into the abdomen, which is more invasive and potentially safe."
Information source: 3-D liver tissue implants made from human stem cells support liver function in mice
Original source: Hassan Rashidi et al, 3D human liver tissue from pluripotent stem cells displays stable phenotype in vitro and supports compromised liver function in vivo, Archives of Toxicology (2018). DOI: 10.1007/s00204-018-2280-2
Ningbo Siny Medical Technology Co., Ltd , https://www.sinymedical.com