Human amniotic epithelial cells have the capacity to differentiate into several different cell types. To that list, we can now add bone.
A study from Steve G.F. Shen at his colleagues at the Shanghai Jiao Tong University School of Medicine, Shanghai, China has used human amniotic epithelial cells to regenerate the tooth sockets in laboratory animals.
The first set of experiments examined the ability of human amniotic epithelial cells (hAECs) to form bone under controlled laboratory conditions. Then hAECs were loaded into artificial scaffolds that were then placed into the mouths of rats with tooth socket defects.
In culture, hAECs expressed bone-specific genes 10-14 days after induction. The cells also changed shape and made bone-specific proteins. When implanted into rat tooth sockets, the hAECs were embedded in a scaffold imbued with growth factors known to induce bone differentiation. These implants improved bone regeneration by directly participating in bone repair of the tooth socket defect. They also had an additional benefit in that they modulated the localized immune response against the implanted scaffolds. This immune response modulation augmented regeneration of the tooth sockets and allowed the implanted cells to get on with the job of fixing the surrounding bone without dealing with insults from the immune system.
This study has provided the first evidence that hAECs exhibit direct involvement in new bone regeneration and a localized modulatory influence on the early tissue remodeling process. These cells indirectly contributed to the bone-making process in the alveolar defect. Altogether, these results imply the potential clinical use of hAECs as an alternative stem cell-based for restoring tooth socket deformities.