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.
Tissue engineered vocal cords. A report from the University of Wisconsin that researchers there had grown new vocal cords got quite a bit of play in the media including this piece on the NBC News web site. It caught my attention not so much because of what they had created, but rather because of the vivid example it provides of cells having a memory of their role and their ability to communicate with each other to function in that role.
In the rather simple experiment, the team took vocal fold tissue from patients who had their larynxes removed for reasons other than cancer. They then used a solution to separate the tissue into individual cells and seeded those cells onto collagen scaffolding. Within 14 days they had fully formed tissue. One of the researchers stated in a phone briefing that the cells knew what they should be doing:
“They’re effectively talking to each other and producing the structural proteins that make this special tissue capable of vibration,” said Brian Frey.
The team transplanted the tissue into a larynx from a deceased dog and was able to demonstrate that the cells could make sound. In the artificial lab setting it evidently sounded a bit like a Kazoo, but the researchers maintained that if transplanted into a human it could easily sound like a voice.
Never ending quest to understand our brain. We’ve known for some time that the gene NeuroD1 plays a critical role in the early development of the brain. Now work by researchers at the Institute of Molecular Biology in Mainz, Germany report that this one gene seems to be the master switch to creating the brain.
They used several popular new techniques to track the activity of NeuroD1 in living tissue. They found it turned on a large number of genes that act to maintain cells’ trajectory to become nerves. Another indication of NeuroD1’s Svengali role came when they realized that even after it is turned off, the other genes stay active and keep driving cells to become more brain tissue.
“Our research has shown how a single factor, NeuroD1, has the capacity to change the epigenetic landscape of the cell, resulting in a gene expression program that directs the generation of neurons,” wrote the investigators in the EMBO Journal.
A story in Genetic Engineering News describes the potential impact this finding could have on understanding brain development as well as in figuring out how to repair brain damage.
Age of donor cells matters. Stem cells in older individuals just don’t do their jobs as well as those in younger people. Now a team at the Miller School of Medicine in Miami has provided clear evidence that this difference matters when selecting donor stem cells—at least in the mice in this study.
The study, published in Translational Research, looked at the ability of mesenchymal stem cells (MSCs) to protect lungs from injury. HealthCanal picked up the institution’s press release that quoted one of the researchers.
“Donor stem cells from younger mice were effective in preventing damage when infused into older mice at the same time as a disease-causing agent,” said Marilyn K. Glassberg. “However, donor MSCs from older mice had virtually no effect.”
The issue becomes key when debating the merits of autologous cells (from the patient themselves) versus allogeneic cells (from donors). This study adds weight to the side that says for older patients choose allogeneic—and make sure the donor is young.