Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Making the most of stem cells

31.03.2004


New storage method amplifies cells available for science



Like many other kinds of cells used in biomedical research, human embryonic stem cells are stored and transported in a cryopreserved state, frozen to -320 degrees Fahrenheit, the temperature of their liquid nitrogen storage bath.

But when scientists thaw the cells for use in the lab, less than 1 percent awake from their frigid slumber and assume their undifferentiated state. This ’blank slate’ form is characteristic of stem cells and essential for the basic science required before the promising cells are ready for the clinic. So scientists are required to place the few survivors in culture and painstakingly tend to them for weeks before new colonies are abundant enough to conduct experiments.


"Human embryonic stem cells have a very low survival rate following cryopreservation, which causes several problems," says Sean Palecek, a University of Wisconsin-Madison professor of chemical and biological engineering.

Not only does that low rate make working with human embryonic stem cells time and labor intensive, but - because so few survive freezing - it may also mean that natural selection is altering the stored cells in unknown and undesired ways, he says.

But now Palecek, along with colleagues Juan de Pablo and Lin Ji, are putting the finishing touches on a new method for preserving and storing the finicky cells. The work, presented today (March 30) at a meeting of the American Chemical Society, promises to greatly amplify the number of cells that survive their enforced hibernation, that remain undifferentiated and that are more readily available for research. What’s more, with more survivors, genetic variability becomes less of an issue.

By freezing the cells attached to a gel matrix instead of suspended in solution, and adding the chemical trehalose - a disaccharide or sugar that some animals and microbes produce to protect cells and survive in dry, low-temperature conditions - the Wisconsin team was able to increase stem cell survival rates by more than an order of magnitude, with as many as 20 percent of a cell culture surviving the freezing-and-thawing process.

"By using the gel and adding the disaccharide to cells, you can increase their chances of survival," notes de Pablo, also a UW-Madison professor of chemical and biological engineering. "Twenty percent survival doesn’t sound like much, but that’s a huge improvement. Taking the few survivors from current methods and growing them takes weeks. It’s a real bottleneck in the field.

"Also, the amount of uncontrolled differentiation is reduced drastically."

The ideal system for preserving and storing valuable cells and other biological materials, says de Pablo, would be one where the cells are freeze-dried, and that’s the ultimate goal of this line of research.

The Wisconsin group has already successfully developed methods for freeze- drying bacterial cultures used to make cheese and yogurt. Their method, now in use commercially, reduces storage and transportation costs for food processors.

"The idea now," explains de Pablo, "is to extend the technology to mammalian cells."

He cites blood products as an example of cells that could potentially be freeze-dried for easy long-term storage, and blood products have become a new focus for his research group.

"If you can freeze-dry these types of cells, you can store them for indefinite amounts of time" and costs would be greatly reduced, he says. Such a technology would also help alleviate the chronic shortages of blood products. Some blood products are perishable and must now be discarded after a certain amount of time in storage. Freeze-dried blood products would have no such liability. Moreover, it would make blood products more readily available for emergencies and mass casualty events, and in remote and difficult settings such as a battlefield environment.

The work by Palecek, de Pablo and Ji, which was supported by a grant from the Defense Advanced Research Projects Agency (DARPA), is also scheduled for publication in an upcoming issue of the journal Biotechnology and Bioengineering. A patent for the technology has been applied for through the Wisconsin Alumni Research Foundation.


- Terry Devitt (608) 262-8282, trdevitt@wisc.edu

Sean P. Palecek | EurekAlert!
Further information:
http://www.wisc.edu/

More articles from Life Sciences:

nachricht Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute

nachricht Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>