A new liver will be grown in the human body for the first time
The first volunteer was injected with donor cells, which will later grow into a new mini liver. If clinical trials are successful, this method of therapy will be revolutionary and will help treat people with severe liver diseases. There are plans to grow kidneys and pancreas in a similar way.
American biotechnology company LyGenesis, headquartered in Pittsburgh, Pennsylvania, has begun clinical trials of its cell therapy: on March 25, the first patient with acute liver failure was injected with donor cells into a lymph node in the upper abdomen to grow a new "mini liver". The press release is published on the Nature journal's website.
The liver is a gland located in the upper right side of the abdomen, above the stomach, right kidney and intestines. This organ performs over 500 vital functions: for example, it produces bile, which helps to eliminate unnecessary substances and break down fats in the small intestine; synthesizes most cholesterol and blood plasma proteins; regulates amino acid levels in the blood and its clotting; participates in the processing and storage of iron (important for providing hemoglobin); and plays the role of the "body's chemical laboratory", cleansing the blood of drugs and bacteria.
In addition, since ancient times (remember the myth of Prometheus), the liver is known for its unique ability to regenerate, that is, it can recover from partial surgical removal or chemical damage by replacing lost tissue. If the human liver is damaged too severely, for example due to alcoholism, hepatitis B or exposure to toxic substances, its structure is damaged by overgrowth of connective tissue - this is called cirrhosis. In such cases, especially if the disease is diagnosed in the late stages, liver transplantation remains the best option.
However, there is a shortage of organs for transplantation worldwide. In the same United States, 10 percent of people waiting for surgery will die before they receive a liver transplant. In addition, such a risky procedure is not always suitable for patients who are very unwell and have experienced the consequences of cirrhosis such as poor blood clotting.
A possible, less invasive, solution could be a new treatment method developed by LyGenesis. It aims to save people with severe liver disease who can't get a transplant, thanks to new miniaturized organs grown in lymph nodes from donor cells.
The plus side of the therapy is also that about 75 people could be cured with just one liver. Including plan to use unusable organs - for example, when a donor's brain has died, his liver can not be transplanted to another patient, but the cells can still be taken.
The approach has previously been tested in mice and pigs, now it's time for clinical trials involving humans. LyGenesis CEO Michael Hufford said the first volunteer has already been discharged from the clinic. He is taking immunosuppressants - drugs to reduce the immune response - to keep his body from rejecting the donor cells, and remains under medical supervision. Over the course of several months, the donor cells will multiply, "taking over" the lymph node, eventually forming a structure that can take over the functions of the liver.
Experiments on rodents with genetic liver disease more than 10 years ago confirmed that most of the cells injected into the lymph node will remain there. Some will "migrate" to the liver, if enough healthy tissue is preserved there, and will help the organ to regenerate. When this happens, the "mini liver" in the lymph node will shrink to maintain the innate balance of the total amount of liver tissue, the researchers said.
"Over time, the lymph node will disappear, leaving a miniature liver with a high degree of vascularization (formation of new blood vessels within the tissue. - Ed. note). It will support the function of the "real" liver by helping to filter the blood. This is exactly what we are now trying to achieve in the human body," Hufford said.