part of part of bone cell meso-epithelial cell endosteal cell 2010-08-24T03:33:58Z A cell type that makes up the highly vascular membrane lining the marrow cavity of long bones. Endosteal cells, also known as osteogenic cells, are a specialized type of cell that resides in the endosteum of the bone marrow cavity. The endosteum is a thin vascular membrane of connective tissue that lines the inner surface of the bony tissue that forms the medullary cavity of long bones. This specific location assigns endosteal cells critical roles in the bone maintenance and regeneration process as they actively participate in bone remodeling, a process that involves both the formation and resorption of bone tissue. Endosteal cells function by regulating the activity of both osteoblasts and osteoclasts. Osteoblasts are cells that deposit new bone, and osteoclasts are responsible for bone resorption, a process important for the maintenance, repair, and remodelling of bones. When new bone tissue is required, such as in instances of bone fractures or increased mechanical stress, endosteal cells differentiate into osteoblasts to facilitate the bone formation process. Conversely, when bone resorption is necessary, these cells are known to release signals that lead to the recruitment and activation of osteoclasts. In addition to this, endosteal cells play a significant role in hematopoiesis, which is the formation of blood cellular components. They function in this process by providing a niche for hematopoietic stem cells, serving to support their maintenance and differentiation. Understanding the functionality of endosteal cells is important in the field of regenerative medicine and stem cell therapy, especially in diseases affecting bone remodeling and hematopoiesis. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) https://cellxgene.cziscience.com/cellguide/CL_0002157 FMA:86495 endosteum