Despite the development of new bioengineering protocols, building a tooth from stem cells remains a distant goal. Demand for it exists as loss of teeth affects oral health, quality of life, as well as one’s appearance. To build a tooth, a detailed recipe to instruct cells to differentiate towards proper lineages and form dental cells is needed. However, the study of stem cells requires their isolation and a lack of a specific marker has hindered studies so far.
Researchers in the group of Professor Irma Thesleff at the Institute of Biotechnology in Helsinki, Finland have now found a marker for dental stem cells. They showed that the transcription factor Sox2 is specifically expressed in stem cells of the mouse incisor (front tooth). The mouse incisor grows continuously throughout life and this growth is fueled by stem cells located at the base of the tooth. These cells offer an excellent model to study dental stem cells.
The researchers developed a method to record the division, movement, and specification of these cells. By tracing the descendants of genetically labeled cells, they also showed that Sox2 positive stem cells give rise to enamel-forming ameloblasts as well as other cell lineages of the tooth.
– Although human teeth don’t grow continuously, the mechanisms that control and regulate their growth are similar as in mouse teeth. Therefore, the discovery of Sox2 as a marker for dental stem cells is an important step toward developing a complete bioengineered tooth. In the future, it may be possible to grow new teeth from stem cells to replace lost ones, says researcher Emma Juuri, a co-author of the study.