Schwann Cells Contribute to Alveolar Bone Regeneration by Promoting Cell Proliferation.

This article focuses on the role of Schwann cells (SCs) in alveolar bone regeneration following injury. Using a Plp-CreER genetic mouse model to trace and ablate proteolipid protein 1 (Plp)-expressing SCs, the study demonstrates that these cells migrate into injured alveolar bone, dedifferentiate into repair SCs, and primarily support bone healing through paracrine secretion rather than direct transdifferentiation into osteogenic cells. The secreted factors from repair SCs enhance the proliferation of alveolar skeletal stem cells (aSSCs) by activating extracellular matrix (ECM) receptors and receptor tyrosine kinases (RTKs), which stimulate downstream ERK/MAPK and PI3K-Akt signaling pathways. Transplantation of peripheral nerves containing SCs accelerates alveolar bone healing, while specific ablation of Plp+ SCs impairs regeneration, underscoring the critical paracrine function of SCs in this process.