Boyan B D, Batzer R, Kieswetter K, Liu Y, Cochran D L, Szmuckler-Moncler S, Dean D D, Schwartz Z
Department of Orthopaedics, University of Texas Health Science Center at San Antonio 78284-7774, USA.
J Biomed Mater Res. 1998 Jan;39(1):77-85. doi: 10.1002/(sici)1097-4636(199801)39:1<77::aid-jbm10>3.0.co;2-l.
Surface roughness has been shown to affect differentiation and local factor production of MG63 osteoblast-like cells. This study examined whether surface roughness alters cellular response to circulating hormones such as 1 alpha,25-(OH)2D3. Unalloyed titanium (Ti) disks were pretreated with HF/HNO3 (PT) and then were machined and acid-etched (MA). Ti disks also were sandblasted (SB), sandblasted and acid etched (CA), or plasma sprayed with Ti particles (PS). The surfaces, from smoothest to roughest, were: PT, MA, CA, SB, and PS. MG63 cells were cultured to confluence on standard tissue culture polystyrene (plastic) or the Ti surfaces and then treated for 24 h with either 10(-8) M or 10(-7) M 1 alpha,25-(OH)2D3 or vehicle (control). Cellular response was measured by assaying cell number, cell layer alkaline phosphatase specific-activity, and the production of osteocalcin, latent (L) TGF beta, and PGE2. Alkaline phosphatase activity was affected by surface roughness; as the surface became rougher, the cells showed a significant increase in alkaline phosphatase activity. Addition of 1 alpha,25-(OH)2D3 to the cultures caused a dose-dependent stimulation of alkaline phosphatase activity that was synergistic with the effect caused by surface roughness alone. 1 alpha,25-(OH)2D3 also caused a synergistic increase in osteocalcin production as well as local factor (LTGF beta and PGE2) production on the rougher CA, SB, and PS surfaces, but it had no effect on the production on smooth surfaces. The inhibitory effect of surface roughness on cell number was not affected by 1 alpha,25-(OH)2D3 except on the SB surface. 1 alpha,25-(OH)2D3 decreased cell number, increased alkaline phosphatase activity and osteocalcin production, and had no effect on LTGF beta or PGE2 production by MG63 cells grown on tissue culture polystyrene. These data suggest that bone cell response to systemic hormones is modified by surface roughness and that surface roughness increases the responsiveness of MG63 cells to 1 alpha,25-(OH)2D3. They also suggest that the endocrine system is actively involved in normal bone healing around implants.
已表明表面粗糙度会影响MG63成骨样细胞的分化和局部因子产生。本研究检测了表面粗糙度是否会改变细胞对循环激素（如1α,25 - (OH)₂D₃）的反应。将未合金化的钛（Ti）盘先用HF/HNO₃预处理（PT），然后进行机械加工和酸蚀（MA）。Ti盘还进行了喷砂处理（SB）、喷砂和酸蚀处理（CA）或用Ti颗粒进行等离子喷涂（PS）。从最光滑到最粗糙的表面依次为：PT、MA、CA、SB和PS。将MG63细胞在标准组织培养聚苯乙烯（塑料）或Ti表面培养至汇合，然后用10⁻⁸ M或10⁻⁷ M的1α,25 - (OH)₂D₃或溶剂（对照）处理24小时。通过测定细胞数量、细胞层碱性磷酸酶比活性以及骨钙素、潜伏（L）转化生长因子β（TGFβ）和前列腺素E2（PGE2）的产生来测量细胞反应。碱性磷酸酶活性受表面粗糙度影响；随着表面变得更粗糙，细胞的碱性磷酸酶活性显著增加。向培养物中添加1α,25 - (OH)₂D₃会引起碱性磷酸酶活性的剂量依赖性刺激，这与单独由表面粗糙度引起的效应具有协同作用。1α,25 - (OH)₂D₃还会使在更粗糙的CA、SB和PS表面上的骨钙素产生以及局部因子（LTGFβ和PGE2）产生协同增加，但对光滑表面上的产生没有影响。表面粗糙度对细胞数量的抑制作用除了在SB表面外不受1α,25 - (OH)₂D₃影响。1α,25 - (OH)₂D₃会减少在组织培养聚苯乙烯上生长的MG63细胞的数量，增加碱性磷酸酶活性和骨钙素产生，并且对LTGFβ或PGE2的产生没有影响。这些数据表明骨细胞对全身激素的反应会因表面粗糙度而改变，并且表面粗糙度会增加MG63细胞对1α,25 - (OH)₂D₃的反应性。它们还表明内分泌系统积极参与植入物周围的正常骨愈合。
