Heymann D, Delécrin J, Deschamps C, Gouin F, Padrines M, Passuti N
EE 99-01, Laboratoire de Physiopathologie de la Résorption Osseuse, Nantes, France.
Rev Chir Orthop Reparatrice Appar Mot. 2001 Feb 1;87(1):8-17.
Bone grafts or bone substitutes are required to fill bone defects resulting from trauma or surgical resection of tumors. Calcium-phosphate ceramics are synthetic bone substitutes which promote new bone formation by osteoconduction. These ceramics possess osteoconductive properties but have no intrinsic osteoinductive capacity. They are unable to induce new bone formation in extraossesous sites. One solution to develop bone substitutes with osteogenic properties would be to associate biomaterials with osteoprogenitors.
We studied the in vitro osteogenic potential of human bone-marrow cells cultured on macroporous calcium phosphate (CaP) ceramic, examining stromal cell proliferation and differentiation. Osteogenic differentiation was evaluated in terms of alkaline phosphatase activity and immunological characterization of the extracellular fibrillar matrix formed by these cells. The specimens were examined by scanning and transmission electron microscopy.
Human bone-marrow cells proliferated on CaP ceramic. The proliferating bone-marrow cells expressed an osteoblastic phenotype as shown by alkaline phosphatase activity and synthesis in ceramic pores of an extracellular matrix composed of fibronectin, osteocalcin and collagen I. In addition, numerous microcrystals of apatite precipitated on the fibrillar matrix, producing a mineralized fibrillar network within the ceramic.
This study demonstrates that human bone-marrow cells cultured on macroporous CaP ceramic do not lose their osteoblastic phenotype even after 21 days of culture, and that they can induce osteogenesis in a CaP ceramic in vitro. This type of new "hybrid material" appears promising for the future.
骨移植或骨替代物是填补创伤或肿瘤手术切除后造成的骨缺损所必需的。磷酸钙陶瓷是一种合成骨替代物，可通过骨传导促进新骨形成。这些陶瓷具有骨传导特性，但没有内在的骨诱导能力。它们无法在骨外部位诱导新骨形成。开发具有成骨特性的骨替代物的一种解决方案是将生物材料与骨祖细胞结合。
我们研究了在大孔磷酸钙（CaP）陶瓷上培养的人骨髓细胞的体外成骨潜力，检测了基质细胞的增殖和分化。根据碱性磷酸酶活性以及这些细胞形成的细胞外纤维状基质的免疫特性评估成骨分化。通过扫描电子显微镜和透射电子显微镜检查标本。
人骨髓细胞在CaP陶瓷上增殖。增殖的骨髓细胞表现出成骨细胞表型，碱性磷酸酶活性以及在陶瓷孔隙中合成由纤连蛋白、骨钙素和I型胶原组成的细胞外基质可证明这一点。此外，大量磷灰石微晶沉淀在纤维状基质上，在陶瓷内部形成矿化的纤维状网络。
本研究表明，在大孔CaP陶瓷上培养的人骨髓细胞即使培养21天后也不会丧失其成骨细胞表型，并且它们能够在体外的CaP陶瓷中诱导成骨。这种新型“混合材料”在未来似乎很有前景。
