Ronneberger B, Kao W J, Anderson J M, Kissel T
Department of Pharmaceutics and Biopharmacy, Philipps University, Marburg, Germany.
J Biomed Mater Res. 1996 Jan;30(1):31-40. doi: 10.1002/(SICI)1097-4636(199601)30:1<31::AID-JBM5>3.0.CO;2-S.
Films of three ABA-block copolymers composed of lactic-co-glycolic acid A blocks and poly(oxyethylene) (PEO) B blocks and one random lactic-co-glycolic acid copolymer (PLG) were studied to investigate the influence of different polymer compositions and molecular weights on the tissue reaction, appearance of toxic degradation products, and swelling behavior in the cage implant system in rats. The inflammatory tissue reaction was followed over a 21-day implantation period by monitoring the leukocyte concentration, the extracellular acid, and alkaline phosphatase activities in a quantitative manner. Size and density of adherent macrophages and foreign body giant cells on the film surfaces were determined. The ABA and PLG implants caused only a minimal inflammatory reaction, as characterized by a low concentration of leukocytes during the implantation period when compared to empty cage controls. The content of PEO had an influence on the density of the adherent cells on the surface of the polymer film. An increase in PEO content and molecular weight decreased the cellular density during the implantation period. As demonstrated by scanning electron microscopy, no degradation was observed for all polymers during the implantation period. Our results demonstrate that the ABA block copolymers and PLG copolymer, are equally well tolerated in the cage implant test system.
研究了由乳酸 - 乙醇酸共聚物A嵌段和聚（氧乙烯）（PEO）B嵌段组成的三种ABA嵌段共聚物薄膜以及一种无规乳酸 - 乙醇酸共聚物（PLG）薄膜，以研究不同聚合物组成和分子量对大鼠笼植入系统中组织反应、有毒降解产物的出现以及肿胀行为的影响。在21天的植入期内，通过定量监测白细胞浓度、细胞外酸和碱性磷酸酶活性来跟踪炎症组织反应。测定了薄膜表面附着巨噬细胞和异物巨细胞的大小和密度。与空笼对照相比，ABA和PLG植入物仅引起最小的炎症反应，其特征是植入期白细胞浓度较低。PEO的含量对聚合物薄膜表面附着细胞的密度有影响。PEO含量和分子量的增加会降低植入期的细胞密度。扫描电子显微镜显示，植入期内所有聚合物均未观察到降解。我们的结果表明，ABA嵌段共聚物和PLG共聚物在笼植入测试系统中具有同样良好的耐受性。
