Xu Yue, Malladi Preeti, Zhou Dimin, Longaker Michael T
Stanford, Calif. From the Children's Surgical Research Program and Department of Surgery, Stanford University School of Medicine.
Plast Reconstr Surg. 2007 Dec;120(7):1783-1795. doi: 10.1097/01.prs.0000279491.48283.51.
Cranial skeletogenic mesenchyme is derived from two distinct embryonic sources: mesoderm and cranial neural crest. Previous studies have focused on molecular and cellular differences of juvenile and adult osteoblasts.
To further understand the features of mouse-derived juvenile osteoblasts, the authors separated calvarial osteoblasts by their developmental origins: frontal bone-derived osteoblasts from cranial neural crest, and parietal bone-derived osteoblasts from paraxial mesoderm. Cells were harvested from a total of 120 mice.
Interestingly, the authors observed distinct morphologies and proliferation potential of the two populations of osteoblasts. Osteogenic genes such as alkaline phosphatase, osteopontin, collagen I, and Wnt5a, which was recently identified as playing a role in skeletogenesis, were abundantly expressed in parietal bone-derived osteoblasts versus frontal bone-derived osteoblasts. In addition, fibroblast growth factor (FGF) receptor 2, and FGF-18 were more highly expressed in the parietal bone-derived osteoblasts, suggesting a more differentiated phenotype. In contrast, FGF-2, and adhesion molecules osteoblast cadherins and bone morphogenetic protein receptor IB, the bone tissue-specific type receptor were overexpressed in frontal bone-derived osteoblasts compared with parietal bone-derived osteoblasts.
The authors observed that although neural crest-derived osteoblasts represented a population of less differentiated, faster growing cells, they formed bone nodules more rapidly than parietal bone-derived osteoblasts. This in vitro study suggests that embryonic tissue derivations influence postnatal in vitro calvarial osteoblast cell biology.
颅骨生骨间充质来源于两个不同的胚胎来源：中胚层和颅神经嵴。以往的研究集中在幼年和成体成骨细胞的分子和细胞差异上。
为了进一步了解小鼠来源的幼年成骨细胞的特征，作者根据其发育起源分离颅盖成骨细胞：来自颅神经嵴的额骨来源的成骨细胞和来自轴旁中胚层的顶骨来源的成骨细胞。共从120只小鼠中采集细胞。
有趣的是，作者观察到这两种成骨细胞群体具有不同的形态和增殖潜力。与额骨来源的成骨细胞相比，在顶骨来源的成骨细胞中大量表达了诸如碱性磷酸酶、骨桥蛋白、I型胶原蛋白和最近被确定在骨骼生成中起作用的Wnt5a等成骨基因。此外，成纤维细胞生长因子（FGF）受体2和FGF-18在顶骨来源的成骨细胞中表达更高，表明其具有更分化的表型。相比之下，与顶骨来源的成骨细胞相比，FGF-2、黏附分子成骨钙黏蛋白和骨组织特异性I型受体骨形态发生蛋白受体IB在额骨来源的成骨细胞中过表达。
作者观察到，尽管神经嵴来源的成骨细胞代表了一群分化程度较低、生长较快的细胞，但它们形成骨结节的速度比顶骨来源的成骨细胞更快。这项体外研究表明，胚胎组织来源会影响出生后体外颅盖成骨细胞的生物学特性。
