Cranial Suture Mesenchymal Stem Cells: Insights and Advances

Abstract

The cranial bones constitute the protective structures of the skull, which surround and protect the brain. Due to the limited repair capacity, the reconstruction and regeneration of skull defects are considered as an unmet clinical need and challenge. Previously, it has been proposed that the periosteum and dura mater provide reparative progenitors for cranial bones homeostasis and injury repair. In addition, it has also been speculated that the cranial mesenchymal stem cells reside in the perivascular niche of the diploe, namely, the soft spongy cancellous bone between the interior and exterior layers of cortical bone of the skull, which resembles the skeletal stem cells’ distribution pattern of the long bone within the bone marrow. Not until recent years have several studies unraveled and validated that the major mesenchymal stem cell population of the cranial region is primarily located within the suture mesenchyme of the skull, and hence, they are termed suture mesenchymal stem cells (SuSCs). Here, we summarized the characteristics of SuSCs, this newly discovered stem cell population of cranial bones, including the temporospatial distribution pattern, self-renewal, and multipotent properties, contribution to injury repair, as well as the signaling pathways and molecular mechanisms associated with the regulation of SuSCs.

The clinical manifestations, molecular mechanisms and treatment of craniosynostosis

“…Another important area of future study is the cranial suture niche environment. Mesenchymal cells within each cranial suture contain functionally indispensable MSCs and are highly heterogeneous ( Farmer et al, 2021 ; Holmes et al, 2021 ; Li et al, 2021 ; Zhao et al, 2015 ). Furthermore, adjacent structures such as the dura mater may contribute to the homeostasis of suture MSCs during development and in suture regeneration ( Yu et al, 2021 ).…”

“…Do the aforementioned key markers affect the fate of MSCs in development and tissue homeostasis of cranial sutures and, if so, how? With cell lineage tracing and gene expression analysis at single-cell resolution, we are discovering a heterogeneous MSC population that contributes to the formation and maintenance of cranial sutures ( Holmes et al, 2021 ; Li et al, 2021 ). Second, mechanical transduction of either tensile or compressive loading can significantly affect suture morphology ( Herring, 2008 ).…”

Conditional knockout of Cdc20 attenuates osteogenesis in craniofacial bones

“…Cranial suture-derived MSCs undergo intramembranous growth to expand cranial bone [10,33]. Similar to long bone marrow-derived MSCs, mandibular bone marrow-derived MSCs and cranial suture-derived MSCs can differentiate into osteoblasts and can be used in tissue engineering.…”

“…Mandibular bone marrow-derived MSCs play a signi cant role in mandibular bone remodeling and healing [7,8]. Cranial sutures serve as the osteogenic front for intramembranous ossi cation, and the major population of cranial bone-derived MSCs is derived from cranial sutures [9,10]. Both types of MSCs possess the ability to differentiate into osteoprogenitors and to further give rise to osteoblasts [11].…”

Tissue Regeneration and Physiological Functional Recovery in Dental and Craniofacial Fields

“…Tissue regeneration and functional recovery in regenerative medicine are based on signaling pathways and molecular mechanisms. Li et al summarized the diversity of cell signaling pathways in the calvaria suture, which is a unique place to construct the cranial bone and protect the brain [ 12 ].…”