Engineers at the University of California, San Diego led a team in developing life-like liver tissue with the help of 3D printing.
The model closely approximates a real human liver’s structure and function, and could be applied to drug screening and disease modeling research.
The study was published in the February 8th edition of Proceedings of the National Academy of Sciences.
The researchers hope that the new liver will help save pharmaceutical companies time and resources, making the production of new drugs more affordable. Pharmaceutical companies will be able to run pilot studies for new treatments without waiting for results from human or animal trials.
"It typically takes about 12 years and $1.8 billion to produce one FDA-approved drug," said Shaochen Chen, NanoEngineering professor at the UC San Diego Jacobs School of Engineering. "That's because over 90 percent of drugs don't pass animal tests or human clinical trials. We've made a tool that pharmaceutical companies could use to do pilot studies on their new drugs, and they won't have to wait until animal or human trials to test a drug's safety and efficacy on patients. This would let them focus on the most promising drug candidates earlier on in the process.”
Shaochen Chen is co-author of the study with Shu Chien, a professor of medicine and Bioengineering, and director of the Institute of Engineering in Medicine at UC San Diego.
The model is able to reproduce the liver’s complex system of delivering blood supply, making it a unique specimen for scientists interested in understanding the combined effect of metabolic and circulation functions on health and disease.
"The liver is unique in that it receives a dual blood supply with different pressures and chemical constituents. Our model has the potential of reproducing this intricate blood supply system, thus providing unprecedented understanding of the complex coupling between circulation and metabolic functions of the liver in health and disease," said Chien.
The artificial liver tissue was created using a novel bioprinting method that Chen’s laboratory developed. The entire structure is only 200 micrometers thick, and can be created in seconds. Other methods take hours. After printing, the structure was cultured for 20 days in vitro.
After culturing, the researchers performed various tests to see how well the tissue performed liver functions, such as albumin secretion and urea production.
The 3D-printed tissue is not the first model of its kind, but it was able to maintain functionality longer than other options. It also had a large amount of an important enzyme that scientists think affects the metabolism of different drugs.
The scientists hope that the new liver model can be used to reproduce and better understand various diseases, including cancer, cirrhosis, hepatitis, and others.
Chen said in the paper, “I think that this will serve as a great drug screening tool for pharmaceutical companies and that our 3D bioprinting technology opens the door for patient-specific organ printing in the future.”