Sawada Shin-Ichi, Iwasaki Yasuhiko, Nakabayashi Nobuo, Ishihara Kazuhiko
Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062, Japan.
J Biomed Mater Res A. 2006 Dec 1;79(3):476-84. doi: 10.1002/jbm.a.30820.
To better understand the effect of 2-methacryloyloxyethyl phosphorylcholine (MPC) copolymer in improving the biocompatibility of segmented polyurethane (SPU), the expression of heat shock protein (HSP) mRNA in HeLa S3 cells adhered on SPU blended with MPC copolymers was measured. Conventionally, MPC copolymers (PMEH) were synthesized by changing the feed ratios of MPC and 2-ethylhexyl methacrylate. X-ray photoelectron spectroscopic analysis of the SPU/PMEH film indicated that the surface concentration of MPC units on the SPU/PMEH film increased with an increase in PMEH composition. HeLa S3 cells were cultured on SPU/PMEH films. The number of adherent cells on the SPU/PMEH films decreased with an increase in the concentration of PMEH. When the PMEH composition was greater than 0.5 wt %, cell adhesion and proliferation decreased markedly. Expressions of HSP27 and HSP47 mRNA were detected using the reverse transcription-polymerase chain reaction (RT-PCR). After incubation for 24 h, both the HSP mRNA expressions in the HeLa S3 cells showed no significant differences among all samples. In HeLa S3 cells that adhered to the SPU film for 48 h, the expressions of HSP27 and HSP47 mRNA increased significantly when compared with those incubated for 24 h. In contrast, the two kinds of mRNA expressions decreased in the HeLa S3 cells that adhered to the SPU/PMEH films for 48 h. From these results, we concluded that PMEH was quite important in suppressing the stress response of adherent HeLa S3 cells. Therefore, SPU/PMEH blend polymers are useful as implantable biomedical materials.
为了更好地理解2-甲基丙烯酰氧乙基磷酰胆碱（MPC）共聚物在改善嵌段聚氨酯（SPU）生物相容性方面的作用，我们测定了黏附在与MPC共聚物共混的SPU上的HeLa S3细胞中热休克蛋白（HSP）mRNA的表达。传统上，通过改变MPC与甲基丙烯酸2-乙基己酯的进料比来合成MPC共聚物（PMEH）。对SPU/PMEH薄膜进行X射线光电子能谱分析表明，随着PMEH组成的增加，SPU/PMEH薄膜上MPC单元的表面浓度增加。将HeLa S3细胞培养在SPU/PMEH薄膜上。随着PMEH浓度的增加，SPU/PMEH薄膜上的贴壁细胞数量减少。当PMEH组成大于0.5 wt%时，细胞黏附和增殖明显下降。使用逆转录-聚合酶链反应（RT-PCR）检测HSP27和HSP47 mRNA的表达。孵育24小时后，所有样品中HeLa S3细胞中的HSP mRNA表达均无显著差异。在黏附于SPU薄膜48小时的HeLa S3细胞中，与孵育24小时相比，HSP27和HSP47 mRNA的表达显著增加。相反，在黏附于SPU/PMEH薄膜48小时的HeLa S3细胞中，这两种mRNA表达下降。从这些结果中，我们得出结论，PMEH在抑制贴壁HeLa S3细胞的应激反应中非常重要。因此，SPU/PMEH共混聚合物可用作可植入生物医学材料。
