Papers by Author: Masataka Ohgaki

Abstract: In cell culture medium containing serum proteins, a layer with a great role in ostelblast-like cell’s growth formed on a HAp ceramics by a coprecipitation with a deposition of a bone-like apatite and an adsorption of serum proteins. The adsorption of proteins is influential in the apatite deposition and the cell adhesion. A component of serum albumin is forming < 80% of total serum proteins, therefore we focused on the serum albumin. The serum albumin was removed from fetal bovine serum by using an albumin removal kit, and then the albumin free cell culture medium was prepared. The bone-like apatite layer was quickly formed on the HAp ceramics in the albumin free medium, however the high cell adhesion property was not confirmed. As a result of investigation of an initial cell adhesion, the initial cell adhesion property of the bone-like apatite layer was not excellent even though the layer contained the serum proteins. Moreover, the layer without serum proteins showed a meager cell adhesion property in every time of the cultivation. Therefore, it was revealed that the adsorption of the serum proteins only on the surface was not enough to the improvement of the cell growth. And a few days cultivation was required for an appearance of the remarkable effect on the cell growth on the layer formed by a coprecipitation reaction about the bone-like deposition apatite and the serum proteins adsorption.

Abstract: Autograft, allograft, and biomaterials had been developed for bone regeneration. In recent year, a tissue engineering technique has been paid much attention for next generation implant. A problem of bone tissue engineering to be solved is a development of the substrate that is suitable for cell adhesion, proliferation, and differentiation. A biomimic scaffold for tissue culture was proposed, and then a cell response on the scaffold was estimated. The scaffold composed by a calcium deficient apatite with an adsorbed serum protein was formed on a ceramic hydroxyapatite (HAp) and surface-modified titanium by a soaking in cell-culture medium supplemented with fetal bovine serum. Excellent results on cell proliferation and cell adhesion were obtained only on osteoblast-like cells (MC3T3-E1). An actin filament in narrow filopodium of the spindle-shaped MC3T3-E1 cells on the ceramic HAp had a regular course. On the other hand, ends of the actin filament of the widely spread cells on the apatite layer with serum protein were scattering. It was suggested that the scattering of the actin end showed an existence of fibronectin, and then tight adhesion would be obtained by the many focal adhesion. Accordingly, the effectiveness of the biomimic scaffold containing serum protein on cell growth was confirmed.