Transplanted stem cells used to grow fully functional lungs in mice

Illustration of a human lung

According to organ donation statistics from the Health Resources & Services Administration, over 113,000 men, women, and children are on the national transplant waiting list as of July 2019. Another person is added to the waiting list every 10 minutes and 20 people die each day waiting for a transplant.

As these statistics highlight, there is a tremendous need for obtaining viable organs for people that are in need of a transplant. It is because of this, that scientists and researchers are exploring ways of using stem cells to potentially grow fully functional organs.

Dr. Hiromitsu Nakauchi, Stanford University

In a CIRM-supported study, Dr. Hiromitsu Nakauchi at Stanford University, in collaboration with Dr. Wellington Cardoso at Columbia University, were able to grow fully functional lungs in mouse embryos using transplanted stem cells. The full study, published in Nature Medicine, suggests that it may be possible to grow human lungs in animals and use them for patients in dire need of transplants or to study new lung treatments.

In the study, the researchers took stem cells and implanted them into modified mouse embryos that either lacked the stem cells necessary to form a lung or were not able to produce enough cells to make a lung. It was found that the implanted stem cells formed fully functional lungs that allowed the mice to live well into adulthood. Additionally, there were no signs of the mouse’s body rejecting the lung tissue composed of donor stem cells.

In a press release, Dr. Cardoso expressed optimism for the study and the potential the results hold:

“Millions of people worldwide who suffer from incurable lung diseases die without treatment due to the limited supply of donor lungs for transplantation. Our study shows that it may eventually be possible to develop new strategies for generating human lungs in animals for transplantation as an alternative to waiting for donor lungs.”

Scientists say they’re one step closer to being able to build a new you, using your own stem cells.

Organ transplant

One of the biggest obstacles to transplanting organs from one person to another is that the immune system of the person getting the new life-saving organ often tries to reject it. The immune cells see the new material as “foreign” and attacks it, sometimes destroying it.

Right now, the only way to prevent that is by using powerful immunosuppressive drugs to keep the patient’s immune system at bay and protect the new organ. It’s effective, but it also comes with some long-term health consequences.

But now researchers at Tel Aviv University in Israel say they may have found a way around that, using the patient’s own stem cells.

The team says it was able to take fatty tissue from patients and, using the iPSC procedure, turn them into other kinds of cells to help repair different kinds of tissue.

In a story in the “Times of Israel”, Prof Tal Dvir, the lead researcher, said this new approach could theoretically be used to engineer any tissue type in the body.

“We were able to create a personalized hydrogel from the materials of the biopsy, to differentiate fatty tissue cells into different cell types and to engineer cardiac, spinal cord, cortical and other tissue implants to treat different diseases. Since both the cells and the material used derive from the patient, the implant does not provoke an immune response, ensuring proper regeneration of the defected organ.”

Dvir says the research, published in the journal Advanced Materials, has only been tested in animals so far but has shown great promise, helping regenerate damaged tissues in mice and rats. Their next goal is to see if they can replicate this in people.

“Theoretically we can work in every disease or disorder that cells are involved in, where tissue is dying. We can create the tissue to fix that injury by a simple injection of materials and cells at the injury site,”

While this has long been a goal of many stem cell researchers around the world, problems translating what looks good in animals into what works in people has invariably slowed down the progress of even the most promising approach. At least so far.

Stem cell study holds out promise for kidney disease

Kidney failure

Image via youtube.com

Kidney failure is the Rodney Dangerfield of diseases, it really doesn’t get the respect it deserves. An estimated 660,000 Americans suffer from kidney failure and around 47,000 people die from it every year. That’s more than die from breast or prostate cancer. But now a new study has identified a promising stem cell candidate that could help in finding a way to help repair damaged kidneys.

Kidneys are the body’s waste disposal system, filtering our blood and cleaning out all the waste products. Our kidneys have a limited ability to help repair themselves but if someone suffers from chronic kidney disease then their kidneys are slowly overwhelmed and that leads to end stage renal disease. At that point the patient’s options are limited to dialysis or an organ transplant.

Survivors hold out hope

Italian researchers had identified some cells in the kidneys that showed a regenerative ability. These cells, which were characterized by the expression of a molecule called CD133, were able to survive injury and create different types of kidney cells.

Researchers at the University of Torino in Italy decided to take these findings further and explore precisely how CD133 worked and if they could take advantage of that and use it to help repair damaged kidneys.

In their findings, published in the journal Stem Cells Translational Medicine, the researchers began by working with a chemotherapy drug called cisplatin, which is used against a broad range of cancers but is also known to cause damage to kidneys in around one third of all patients. The team found that CD133 was an important factor in helping those damaged kidneys recover. They also found that CD133 prevents aging of kidney progenitor cells, the kind of cell needed to help create new cells to repair the kidneys in future.

Hope for further research

The finding opens up a number of possible lines of research, including exploring whether infusions of CD133 could help patients whose kidneys are no longer able to produce enough of the molecule to help repair damage.

In an interview in DD News, Dr. Anthony Atala, Director of the Wake Forest Institute for Regenerative Medicine – praised the research:

“This is an interesting and novel finding. Because the work identifies mechanisms potentially involved in the repair of tissue after injury, it suggests the possibility of new therapies for tissue repair and regeneration.”

CIRM is funding several projects targeting kidney disease including four clinical trials for kidney failure. These are all late-stage kidney failure problems so if the CD133 research lives up to its promise it might be able to help people at an earlier stage of disease.