Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study reveals critical similarity between two types of do-it-all stem cells

12.09.2011
Ever since human induced pluripotent stem cells were first derived in 2007, scientists have wondered whether they were functionally equivalent to embryonic stem cells, which are sourced in early-stage embryos.

Both cell types have the ability to differentiate into any cell in the body, but their origins – in embryonic and adult tissue – suggest that they are not identical.

Although both cell types have great potential in basic biological research and in cell- and tissue-replacement therapy, the newer form, called IPS cells, have two advantages. They face less ethical constraint, as they do not require embryos. And they could be more useful in cell replacement therapies: growing them from the patient's own cells would avoid immune rejection.

But until IPS cells are proven to have the same traits as embryonic stem cells, they cannot be considered to be identical.

In a study published today (Sunday, Sept. 11), researchers at the University of Wisconsin-Madison report the first full measurement of the proteins made by both types of stem cells. In a study that looked at four embryonic stem cells and four IPS cells, the proteins turned out to be 99 percent similar, says Joshua Coon, an associate professor of chemistry and biomolecular chemistry who directed the project.

"We looked at RNA, at proteins, and at structures on the proteins that help regulate their activity, and saw substantial similarity between the two stem-cell types," he says.

Proteins are complex molecules made by cells for innumerable structural and chemical purposes, and the new study measured more than 6,000 individual proteins using highly accurate mass spectrometry, a technique that measures mass as the first step of identifying proteins.

The study in Nature Methods, published online, is the first comprehensive comparison of proteins in the two stem cell types, says Doug Phanstiel, who is now at Stanford University, and worked with Justin Brumbaugh on the project as graduate students at UW-Madison.

"From a biological standpoint, what is novel is that this is the first proteomic comparison of embryonic stem cells and IPS cells," says Phanstiel, referring to the study of which proteins a cell produces.

In essence, every cell in the body has the genes to make any protein the body might need, but cells make only the proteins that further their own biological role. Cells regulate the formation and activity of proteins in three ways: first, by controlling the production of RNA, a molecule that transfers the DNA code to protein-making structures; second, by controlling the quantity of each protein made; and third, by adding structures to the protein that regulate when it will be active.

The new study measured each of these activities, Phanstiel says.

"And because we compared four lines of each type of stem cell, and the comparisons were run three times, the statistics are extremely robust," he adds.

The new report, Coon says, suggests that embryonic stem cells and IPS cells are quite similar. According to some measurements, the protein production of an embryonic stem cell was closer to that of an IPS cell than to a second embryonic stem cell.

The ability to measure proteins in such detail emerged from improved ways to measure mass, Coon says.

"New technical developments in both our ability to measure a protein's mass – accurate to the third or fourth decimal place – and to compare the proteins from up to eight different cell lines at a time -- permitted this important comparison for the first time," says Coon.

The study is not the last word in determining the similarity of the two types of pluripotent stem cells, says Coon, who worked with UW-Madison stem-cell pioneer James Thomson, on the project.

Because clinical uses of either type of stem cells will require that they be transformed into more specialized cells, researchers still need to know more about protein production after a stem cell is differentiated into, for example, a neuron or heart muscle cell.

This technology, Coon says, "is now well-positioned to study how closely molecules contained in these promising cells change after they are differentiated into the cells that do the work in our bodies – a critical next step in regenerative medicine."

David Tenenbaum, (608) 265-8549, djtenenb@wisc.edu

Joshua Coon | EurekAlert!
Further information:
http://www.wisc.edu

More articles from Life Sciences:

nachricht Researchers uncover protein-based “cancer signature”
05.12.2016 | Universität Basel

nachricht The Nagoya Protocol Creates Disadvantages for Many Countries when Applied to Microorganisms
05.12.2016 | Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen 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: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

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...

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

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>