To prove the cells' regenerative powers, bone cells grown on this surface were then transplanted into holes in the skulls of mice, producing four times as much new bone growth as in the mice without the extra bone cells.
An embryo's cells really can be anything they want to be when they grow up: organs, nerves, skin, bone, any type of human cell. Adult-derived "induced" stem cells can do this and better. Because the source cells can come from the patient, they are perfectly compatible for medical treatments.
In order to make them, Paul Krebsbach, professor of biological and materials sciences at the U-M School of Dentistry, said, "We turn back the clock, in a way. We're taking a specialized adult cell and genetically reprogramming it, so it behaves like a more primitive cell."
Specifically, they turn human skin cells into stem cells. Less than five years after the discovery of this method, researchers still don't know precisely how it works, but the process involves adding proteins that can turn genes on and off to the adult cells.
Before stem cells can be used to make repairs in the body, they must be grown and directed into becoming the desired cell type. Researchers typically use surfaces of animal cells and proteins for stem cell habitats, but these gels are expensive to make, and batches vary depending on the individual animal.
"You don't really know what's in there," said Joerg Lahann associate professor of chemical engineering and biomedical engineering.
For example, he said that human cells are often grown over mouse cells, but they can go a little native, beginning to produce some mouse proteins that may invite an attack by a patient's immune system.
The polymer gel created by Lahann and his colleagues in 2010 avoids these problems because researchers are able to control all of the gel's ingredients and how they combine.
"It's basically the ease of a plastic dish," said Lahann. "There is no biological contamination that could potentially influence your human stem cells."
Lahann and colleagues had shown that these surfaces could grow embryonic stem cells. Now, Lahann has teamed up with Krebsbach's team to show that the polymer surface can also support the growth of the more medically promising induced stem cells, keeping them in their high-potential state. To prove that the cells could transform into different types, the team turned them into fat, cartilage and bone cells.
They then tested whether these cells could help the body to make repairs. Specifically, they attempted to repair five-millimeter holes in the skulls of mice. The weak immune systems of the mice didn't attack the human bone cells, allowing the cells to help fill in the hole.
After eight weeks, the mice that had received the bone cells had 4.2 times as much new bone, as well as the beginnings of marrow cavities. The team could prove that the extra bone growth came from the added cells because it was human bone.
"The concept is not specific to bone," said Krebsbach. "If we truly develop ways to grow these cells without mouse or animal products, eventually other scientists around the world could generate their tissue of interest."
In the future, Lahann's team wants to explore using their gel to grow stem cells and specialized cells in different physical shapes, such as a bone-like structure or a nerve-like microfiber.
The paper reporting this work is titled "Derivation of Mesenchymal Stem Cells from Human Induced Pluripotent Stem Cells Cultured on Synthetic Substrates" and it appears in the June edition of the journal Stem Cells. The university is pursuing patent protection for the intellectual property and is seeking commercialization partners to help bring the technology to market.
Krebsbach is also the Roy H. Roberts Professor of Dentistry and a professor of biomedical engineering. Lahann is also associate professor of materials sciences and engineering, associate professor of macromolecular sciences and engineering, and the director of the Biointerfaces Institute.
Kate McAlpine | EurekAlert!
New insights into the information processing of motor neurons
22.02.2017 | Max Planck Florida Institute for Neuroscience
Wintering ducks connect isolated wetlands by dispersing plant seeds
22.02.2017 | Utrecht University
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
22.02.2017 | Power and Electrical Engineering
22.02.2017 | Life Sciences
22.02.2017 | Innovative Products