Andersson M, Suska F, Johansson A, Berglin M, Emanuelsson L, Elwing H, Thomsen P
Department of Cell and Molecular Biology/Interface Biophysics Lundberg Laboratory, Göteborg University, Box 462, SE-405 30 Göteborg, Sweden.
J Biomed Mater Res A. 2008 Mar 1;84(3):652-60. doi: 10.1002/jbm.a.31389.
Although numerous different polymers are used as implants or otherwise studied for many other biotechnical applications, there is a lack of basic models that correlate polymer characteristics with foreign body reactions. This study aims at developing one such model by systematically studying surface molecular mobility of polymeric implants in soft tissues in vivo. Changing the length of the alkyl side chain of poly(alkyl methacrylates) (PAMAs), provides an interesting opportunity to study the surface molecular mobility with minimal changes of the hydrophobicity of the surface. Thus, in this study three different PAMAs, with increasingly surface mobility; poly (isobutyl methacrylate) (PIBMA), poly(butyl methacrylate) (PBMA), and poly(lauryl methacralate) (PLMA) along with pure titanium (Ti) substrates were implanted in the dorsum of Sprague-Dawley rats. Inflammatory cell recruitment, cell adhesion, and cytokine release were studied after 1, 3, and 28 days of implantation. Total number of inflammatory cells in the exudate was measured but no correlation between surface mobility and cell recruitment where found. However, the number of surface associated cells where significantly lower on the surfaces with high molecular mobility (PLMA and PBMA). The histological evaluation performed after 28 days revealed thicker fibrous capsule and a higher number of blood vessels on the low molecular mobility surface (PIBMA). After 28 days the cell activity was higher on the high molecular mobility surfaces (PLMA and PBMA) compared with PIBMA, based on the cytokine release. None of the surfaces induced any significant cell-death. On the basis of the results of this study we conclude that there is a significant difference in biological response to surfaces with different in molecular mobility. This might affect the wound healing process and the biocompatibility of biomaterials.
尽管许多不同的聚合物被用作植入物或用于许多其他生物技术应用的研究，但缺乏将聚合物特性与异物反应相关联的基础模型。本研究旨在通过系统地研究体内软组织中聚合物植入物的表面分子流动性来开发这样一种模型。改变聚甲基丙烯酸烷基酯（PAMAs）的烷基侧链长度，提供了一个有趣的机会来研究表面分子流动性，同时使表面疏水性的变化最小。因此，在本研究中，将三种具有逐渐增加的表面流动性的不同PAMAs，即聚甲基丙烯酸异丁酯（PIBMA）、聚甲基丙烯酸丁酯（PBMA）和聚甲基丙烯酸月桂酯（PLMA）以及纯钛（Ti）基材植入Sprague-Dawley大鼠的背部。在植入1、3和28天后，研究了炎症细胞募集、细胞粘附和细胞因子释放。测量了渗出物中炎症细胞的总数，但未发现表面流动性与细胞募集之间的相关性。然而，在高分子流动性表面（PLMA和PBMA）上，表面相关细胞的数量明显较低。28天后进行的组织学评估显示，低分子流动性表面（PIBMA）上的纤维囊更厚，血管数量更多。基于细胞因子释放，28天后高分子流动性表面（PLMA和PBMA）上的细胞活性高于PIBMA。没有一个表面诱导任何明显的细胞死亡。基于本研究的结果，我们得出结论，对具有不同分子流动性的表面的生物学反应存在显著差异。这可能会影响伤口愈合过程和生物材料的生物相容性。
