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 Tag it EASI – a new method for accurate protein analysis
19.06.2018 | Max-Planck-Institut für Biochemie

nachricht How to track and trace a protein: Nanosensors monitor intracellular deliveries
19.06.2018 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Carbon nanotube optics provide optical-based quantum cryptography and quantum computing

19.06.2018 | Physics and Astronomy

How to track and trace a protein: Nanosensors monitor intracellular deliveries

19.06.2018 | Life Sciences

New material for splitting water

19.06.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>