Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.
“Organoids” screen for cystic fibrosis drugs. Starting with iPS-type stem cells made by reprogramming skin cells from cystic fibrosis (CF) patients a team at the University of Cambridge in the U.K. created mini lungs in a dish. These organoids should provide a great tool for screening drugs to treat the disease.
The researchers pushed the stem cells to go through the early stages of embryo development and then on to become 3-D distal airway tissue, the part of the lung that processes gas exchange. They were able to use a florescent marker to show an aspect of the cells’ function that was different in cells from CF patients and those from normal individuals. When they treated the CF cells with a drug that is being tested in CF patients, they saw the function correct to the normal state.
Bioscience Technology picked up the university’s press release about the work published in the journal Stem Cells and Development. It quotes the scientist who led the study, Nick Hannon, on the application of the new tool:
“We’re confident this process could be scaled up to enable us to screen tens of thousands of compounds and develop mini-lungs with other diseases such as lung cancer and idiopathic pulmonary fibrosis.”
To repair a brain knock its “pinky” down. A team at the University of California, San Francisco, has discovered a molecule that when it is shut down nerve stem cells can produce a whole lot more nerves. They call the molecule Pnky, named after the cartoon Pinky and the Brain.
Pkny belongs to a set of molecules known as long noncoding RNAs (lncRNAs), which researchers are finding are more abundant and more important than originally thought. The most familiar RNAs are the intermediary molecules between the DNA in our genes and the proteins that let our cells function. Initially, all the noncoding RNAs were thought to have no function, but in recent years many have been found to have critical roles in determining which genes are active. And Pnky seems to tamp down the activity of nerve stem cells. In a university press release picked up by HealthCanal Daniel Lim, the head researcher explained what happens when they shut down the gene:
“It is remarkable that when you take Pnky away, the stem cells produce many more neurons. These findings suggest that Pnky, and perhaps lncRNAs in general, could eventually have important applications in regenerative medicine and cancer treatment.”
Lim went onto explain the cancer connection. Since Pnky binds to a protein found in brain tumors, it might be involved in regulating the growth of brain tumors. A lot more work needs to happen before that hunch—or the use of Pnky blockers in brain injury—can lead to therapies, but this study certainly paints an intriguing path forward.
Stem cells and Type 2 diabetes. A few teams have succeeded in using stem cells to produce insulin-secreting tissue to correct Type 1 diabetes in animals, but it has been uncertain if the procedure would work for Type 2 diabetes. Type 1 is marked by a lack of insulin production, while resistance to the body’s own insulin, not lack of insulin, is the hallmark of type 2. A team at the University of British Columbia has new data showing stem cell therapy may indeed have a place in treating Type 2.
In mice fed a high fat diet until they developed the symptoms of Type 2 diabetes the stem cell-derived cells did help, but they did not fully correct the metabolism of the mice until they added one of the drugs commonly used to treat diabetes today. The drugs alone, also did not restore normal metabolism, which is often the case with human Type 2 diabetics.
The combination of drugs and cells improved the mice’s sugar metabolism, body weight and insulin sensitivity. The research appeared in the journal Stem Cell Reports and the University’s press release was picked up by several outlets including Fox News.
They transplanted cells from humans and even though the mice were immune suppressed, they took the added measure of protecting the cells in an encapsulation device. They noted that this would be required for use in humans and showing that it worked in mice would speed up any human trials. They also gave a shout out to the clinical trial CIRM funds at Viacyte, noting that since the Food and Drug Administration has already approved use of a similar device by Viacyte, the work might gain more rapid approval.