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 Programming cells with computer-like logic
27.07.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht Identified the component that allows a lethal bacteria to spread resistance to antibiotics
27.07.2017 | Institute for Research in Biomedicine (IRB Barcelona)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Physicists Design Ultrafocused Pulses

Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.

Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

Programming cells with computer-like logic

27.07.2017 | Life Sciences

Identified the component that allows a lethal bacteria to spread resistance to antibiotics

27.07.2017 | Life Sciences

Malaria Already Endemic in the Mediterranean by the Roman Period

27.07.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>