Reddi A H, Ma S S, Cunningham N S
Bone Cell Biology Section, National Institute of Dental Research, Bethesda, Md.
Ann Chir Gynaecol. 1988;77(5-6):189-92.
The cell biology of bone formation can be better understood by dissecting the complex multistep process into individual steps. It is well known that demineralized matrix has the potential to initiate new bone formation locally at a heterotopic site of implantation. The sequential development of bone in response to bone matrix is reminiscent of the cellular lineages in the epiphyseal growth plate. The developmental cascade has permitted the operational distinction of the major phases of new bone formation such as: migration of progenitor cells; mitosis of mesenchymal stem cells; differentiation to cartilage and bone; mineralization and remodelling; and finally hematopoietic marrow differentiation. Thus the initiation of bone formation can be investigated as opposed to maintenance of already formed bone as in the orthotopic sites. Recent work has resulted in the identification and isolation of osteogenin, a bone-inductive protein. The newly formed bone is then maintained by a variety of polypeptide growth factors which have a regulatory role. The local action of initiation and maintenance factors is further modulated in a collaborative manner by systemic factors such as hormones and nutrition and the extracellular matrix.
通过将复杂的多步骤过程分解为各个步骤，可以更好地理解骨形成的细胞生物学。众所周知，脱矿质基质有潜力在植入的异位部位局部启动新的骨形成。响应骨基质的骨的顺序发育让人想起骨骺生长板中的细胞谱系。这种发育级联使得能够对新骨形成的主要阶段进行操作性区分，例如：祖细胞迁移；间充质干细胞的有丝分裂；向软骨和骨的分化；矿化和重塑；以及最终造血骨髓分化。因此，可以研究骨形成的起始，这与在原位部位对已形成骨的维持情况不同。最近的研究工作已导致鉴定和分离出一种骨诱导蛋白——骨生成素。然后，多种具有调节作用的多肽生长因子维持新形成的骨。诸如激素、营养和细胞外基质等全身因素以协同方式进一步调节起始因子和维持因子的局部作用。
