Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists discover unique source of stem cells

22.04.2003


Scientists report for the first time that "baby" teeth, the temporary teeth that children begin losing around their sixth birthday, contain a rich supply of stem cells in their dental pulp. The researchers say this unexpected discovery could have important implications because the stem cells remain alive inside the tooth for a short time after it falls out of a child’s mouth, suggesting the cells could be readily harvested for research.



According to the scientists, who published their findings online today in the Proceedings of the National Academy of Sciences, the stem cells are unique compared to many "adult" stem cells in the body. They are long lived, grow rapidly in culture, and, with careful prompting in the laboratory, have the potential to induce the formation of specialized dentin, bone, and neuronal cells. If followup studies extend these initial findings, the scientists speculate they may have identified an important and easily accessible source of stem cells that possibly could be manipulated to repair damaged teeth, induce the regeneration of bone, and treat neural injury or disease.

"Doctors have successfully harvested stem cells from umbilical cord blood for years," said Dr. Songtao Shi, a scientist at NIH’s National Institute of Dental and Craniofacial Research (NIDCR) and the senior author on the paper. "Our finding is similar in some ways, in that the stem cells in the tooth are likely latent remnants of an early developmental process."


Shi and colleagues named the cells SHED, which stands for Stem cells from human exfoliated deciduous teeth. The term "deciduous teeth" is the formal name for what most people call colloquially "baby teeth." Children normally develop a set of 20 deciduous teeth, which appear after six months of life and generally are replaced, one tooth at a time, between age 6 and 12.

Shi said the unique acronym was needed to differentiate SHED from stem cells in adult tissues, such as bone or brain. "Stem cell research has exploded during the past seven or eight years, yet people still talk in general terms of postnatal and adult stem cells as though they are one and the same. Postnatal cells from children may act totally differently than adult stem cells, and we felt the inherent difference needed to be emphasized," said Shi.

Today’s finding, as so often happens in science, stems from a chance interaction. As Shi recounts, it happened one evening when his then-six-year-old daughter, Julia, asked for help in pulling out a loose baby tooth. "Once it was out, we sat and looked carefully at the tooth," recalled Shi, a pediatric dentist. "I said, ’Wait a minute, there is some red colored tissue inside of the tooth,’ so I took the tooth to my laboratory the next day and examined it. Sure enough, it had beautiful pulp tissue left over."

A few days later, when another of Julia’s teeth came out, Shi said he was better prepared. He placed the tooth into a liquid medium used to culture cells, drove it to the laboratory, and extracted the dental pulp. Soon thereafter, he succeeded in isolating living stem cells from the tissue, a discovery that would lead to the collection of more exfoliated teeth from Julia and other children.

The group launched an initial round of studies to determine whether the cells would grow well in culture. Using dental pulp extracted from the children’s exfoliated incisors, they discovered that about 12 to 20 stem cells from each tooth reproducibly had the ability to colonize and grow in culture.

"We also found the SHED behaved much differently than dental pulp stem cells from permanent teeth, which our group studied previously," said Dr. Masako Miura, an NIDCR scientist and a lead author on the study. "They exhibited an ability to grow much faster and doubled their populations in culture at a greater rate, suggesting SHED may be in a more immature state than adult stem cells."

Interestingly, Muria said she and her colleagues soon found these cells could be prompted to express proteins on their surface indicative of stem cells that were in the process of switching into bone and dental pulp cells. This discovery led to additional followup experiments, led by Dr. Bai Lu of NIH’s National Institute of Child Health and Human Development (NICHD), to determine whether SHED also possessed the potential to switch into neural and fat cells. The groups found, under specific cell culture conditions, the cells responded accordingly, expressing a variety of proteins indicative of neural and fat cells. "These data are just the start," said Shi. "We’re trying to characterize more fully which cell types can be generated from these stem cells. Can they be switched into nerve cells only? We need to find this out. We’re also interested in determining the difference between adult dental pulp stem cells and those in deciduous teeth."


The NIDCR and NICHD are research components of the federal National Institutes of Health (NIH), part of the U.S. Department of Health and Human Services.

Bob Kuska | EurekAlert!
Further information:
http://www.nidr.nih.gov/

More articles from Life Sciences:

nachricht New way to look at cell membranes could change the way we study disease
19.11.2018 | University of Oxford

nachricht Controlling organ growth with light
19.11.2018 | European Molecular Biology Laboratory

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Coherence Tomography: German-Japanese Research Alliance hosted Medical Imaging Conference

19.11.2018 | Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

 
Latest News

New materials: Growing polymer pelts

19.11.2018 | Materials Sciences

Earthquake researchers finalists for supercomputing prize

19.11.2018 | Information Technology

Controlling organ growth with light

19.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>