Schmidmaier G, Wildemann B, Lübberstedt M, Haas N P, Raschke M
Department of Trauma and Reconstructive Surgery, Charité, Campus Virchow, Humboldt-University of Berlin, Augustenburger Platz 1, D-13353 Berlin, Germany.
J Biomed Mater Res B Appl Biomater. 2003 Apr 15;65(1):157-62. doi: 10.1002/jbm.b.10513.
Previous in vivo studies revealed a stimulating effect of locally applied IGF-I and TGF-beta1 released from poly(D,L-lactide)-coated titanium implants on rat and porcine fracture healing. The purpose of the present study was to evaluate the effect of IGF-I (5% w/w) and TGF-beta1 (1% w/w) and the carrier PDLLA on osteoblasts in cell culture to improve the understanding of these growth factors. The well-characterized human osteoblast cell line hFOB 1.19 was used in the study. The implants and cells were cocultured in a noncontact manner. The cells were incubated for 10 days in total, and the implants (n = 6 each group and time point) were added for 1 h, 12 h, 24 h, 2 d, 4 d, or 10 d. To analyze a possible effect of the growth factors or the coating, cell proliferation, metabolism, and differentiation were investigated. As an indicator for differentiation the production of collagen I was chosen. All experimental groups showed comparable cell vitality. No change in the pH of the medium was detectable between the analyzed groups. When the effect of the titanium implant and the PDLLA coating were compared with the control culture, no differences in proliferation, metabolic activity, and collagen I production were detectable. The osteoblasts treated with IGF-I and TGF-beta1 released from PDLLA revealed a significantly enhanced collagen I production with a decrease in proliferation and metabolic activity compared to the other groups. No significant differences in collagen I production were seen due to the incubation time points. None of the experimental groups evoked an immunological response on mouse macrophages. In conclusion, the PDLLA-carrier showed no negative effect on osteoblasts, whereas the incorporated growth factors stimulated osteoblast differentiation.
先前的体内研究表明，聚（D，L-丙交酯）涂层钛植入物释放的局部应用的IGF-I和TGF-β1对大鼠和猪的骨折愈合具有刺激作用。本研究的目的是评估IGF-I（5% w/w）、TGF-β1（1% w/w）及其载体聚（D，L-丙交酯）（PDLLA）对细胞培养中骨细胞的影响，以增进对这些生长因子的了解。本研究使用了特征明确的人成骨细胞系hFOB 1.19。植入物和细胞以非接触方式共培养。细胞总共培养10天，在1小时、12小时、24小时、2天、4天或10天时加入植入物（每组每个时间点n = 6）。为了分析生长因子或涂层的可能作用，研究了细胞增殖、代谢和分化情况。选择I型胶原蛋白的产生作为分化指标。所有实验组的细胞活力相当。在分析的各组之间未检测到培养基pH值的变化。当将钛植入物和PDLLA涂层的作用与对照培养进行比较时，在增殖、代谢活性和I型胶原蛋白产生方面未检测到差异。与其他组相比，用从PDLLA释放的IGF-I和TGF-β1处理的成骨细胞显示I型胶原蛋白产生显著增强，同时增殖和代谢活性降低。由于孵育时间点不同，I型胶原蛋白产生未见显著差异。没有一个实验组对小鼠巨噬细胞引发免疫反应。总之，PDLLA载体对成骨细胞没有负面影响，而掺入的生长因子刺激了成骨细胞分化。
