Bone lining cell

Bone lining cells are flat, quiescent cells derived from inactive osteoblasts that cover the majority of inactive bone surfaces, especially in the adult skeleton. They interconnect with each other and neighboring osteocytes via gap junctions and play critical roles in maintaining bone matrix, regulating mineral exchange and ion flux between bone and interstitial fluids, propagating signals necessary to initiate bone remodeling, and potentially serving as osteogenic precursors. Bone lining cells constitute the periosteal (outer) and endosteal (inner) layers and are essential for minute-to-minute mineral homeostasis, physical barrier protection, and may contribute to hematopoietic microenvironment regulation within bone marrow. Although important for skeletal homeostasis, bone lining cells themselves are not direct molecular therapeutic targets.

Other names

Quiescent osteoblastsurface osteocyte (occasionally)Resting osteoblastPeriosteal cell (outer surface)Endosteal cell (internal surface)