Lentz A J, Horbett T A, Hsu L, Ratner B D
J Biomed Mater Res. 1985 Nov-Dec;19(9):1101-15. doi: 10.1002/jbm.820190919.
Macrophage adhesion to a wide variety of substrates has been measured, but no systematic study of the influence of specific substrate chemical properties on adhesion is available. These studies were conducted using two series of materials, copolymers of hydroxyethyl methacrylate (HEMA) and ethyl methacrylate (EMA) and copolymers of hydroxystyrene and styrene, to determine the effect of a single chemical property, polar character, on adhesion. Rat peritoneal macrophages were allowed to contact polymer substrates for periods ranging from 1 to 240 min before being subjected to a shear stress of 60-120 dynes/cm2 in a thin-channel flow cell. Percentage adhesion was calculated from the number of cells that remained adherent to the substrate after 30 s of applied shear stress. Macrophages remained adherent to 100% EMA and all hydroxystyrene-styrene copolymer surfaces after only 1 min of contact. In copolymers of the HEMA-EMA series, the time required to attain peak adhesion levels increased with increasing substrate hydrophilicity (increasing HEMA content). Cells did not attach to the 20% EMA/80% HEMA copolymer and the 100% HEMA polymer. The results demonstrate that there is a time delay between contact and adhesion of the cells to surfaces of increasing hydrophilicity within the HEMA-EMA series and no time delay with the hydroxystyrene-styrene series. The time delay is thought to be a function of the excluded volume provided by polymers that are able to undergo significant chain rotation and or swelling in the solvent, water. Small excluded volumes present in copolymers of high EMA content and all hydroxystyrene-styrene copolymers offer little or no resistance to formation of adhesive bonds by macrophages, whereas copolymers with large excluded volumes (high HEMA content) prevent contact and/or adhesion. A mechanism based on the net excluded volumes of both the cell and substrate surface macromolecule is proposed to explain this phenomenon.
已经对巨噬细胞与多种底物的黏附进行了测量，但尚无关于特定底物化学性质对黏附影响的系统性研究。这些研究使用了两组材料，甲基丙烯酸羟乙酯（HEMA）和甲基丙烯酸乙酯（EMA）的共聚物以及羟基苯乙烯和苯乙烯的共聚物，以确定单一化学性质，即极性特征，对黏附的影响。在薄通道流动池中对大鼠腹膜巨噬细胞施加60 - 120达因/平方厘米的剪切应力之前，让其与聚合物底物接触1至240分钟。根据施加剪切应力30秒后仍附着在底物上的细胞数量计算黏附百分比。巨噬细胞仅接触1分钟后就保持100%附着在EMA以及所有羟基苯乙烯 - 苯乙烯共聚物表面。在HEMA - EMA系列共聚物中，达到峰值黏附水平所需的时间随着底物亲水性的增加（HEMA含量增加）而增加。细胞不会附着在20% EMA / 80% HEMA共聚物和100% HEMA聚合物上。结果表明，在HEMA - EMA系列中，细胞与亲水性增加的表面接触和黏附之间存在时间延迟，而在羟基苯乙烯 - 苯乙烯系列中则没有时间延迟。这种时间延迟被认为是能够在溶剂水（water）中发生显著链旋转和/或溶胀的聚合物所提供的排除体积的函数。高EMA含量的共聚物和所有羟基苯乙烯 - 苯乙烯共聚物中存在的小排除体积对巨噬细胞形成黏附键几乎没有或没有阻力，而具有大排除体积（高HEMA含量）的共聚物则会阻止接触和/或黏附。提出了一种基于细胞和底物表面大分子净排除体积的机制来解释这一现象。
