课题背景：聚乳酸是继聚乙醇酸之后第二类经FDA批准可用于人体的可降解聚合物材料。但聚乳酸表面疏水性强，严重影响了其与细胞的亲和性，以及应用于人体的可行性。为此，本实验旨在揭示改性聚乳酸材料对MC3T3-E1细胞生物学行为的影响。

应用要点：马来酸酐改性聚乳酸和丁二胺改性聚乳酸具有比聚（DL-乳酸）更强的促进MC3T3-E1成骨前体细胞增殖和分化的能力，就细胞生理功能而言，改性聚乳酸比聚乳酸具有更好的成骨细胞相容性。

重要的概念：聚乳酸在体内虽可降解，但其降解物积累在体内成酸性，降解速度需要控制；而且聚乳酸材料缺乏丰富的活性基团，不利于向其中共价引入多肽、胶原等生物信号分子，使其不易成为具有生物专一性的生物活性材料；缺乏细胞识别信号、与组织细胞难以有生物特异性相互作用。聚乳酸的这些弊端制约了其在生物医学工程中的应用，同时也激发了人们对聚乳酸改性的研究兴趣。

摘要
目的：聚乳酸是经FDA批准可进入人体的生物可降解材料，因其表面疏水性强，与细胞亲和力差，所显示的生物相容性较差。
目的：观察MC3T3-E1成骨前体细胞在马来酸酐改性聚乳酸和丁二胺改性聚乳酸表面的黏附情况，评价改性聚乳酸的细胞相容性，并与聚（DL-乳酸）对比。
设计、时间及地点：对比实验，于2007-06在重庆大学生物工程学院生物材料与仿生工程研究中心完成。
材料：聚（DL-乳酸）、马来酸酐改性聚乳酸和丁二胺改性聚乳酸为自制；MC3T3-E1细胞株购自上海细胞生物研究所。
方法：采用体外培养细胞的方法，将MC3T3-E1细胞直接接种到聚（DL-乳酸）、马来酸酐改性聚乳酸和丁二胺改性聚乳酸材料上。
主要观察指标：通过细胞形态、细胞增殖、细胞周期、细胞黏附检测比较不同基底材料对MC3T3-E1成骨前体细胞的影响。
结果：MC3T3-E1成骨前体细胞在马来酸酐及丁二胺改性聚乳酸膜上的增殖速率和黏附力大于聚（DL-乳酸）(P < 0.05)；细胞周期测定显示马来酸酐及丁二胺改性聚乳酸膜能促进MC3T3-E1成骨前体细胞从G0期向S期和G2/M期过渡，细胞形态也较为成熟。
结论：马来酸酐改性的聚乳酸和丁二胺改性的聚乳酸能促进MC3T3-E1成骨前体细胞黏附、增殖，并促进其更迅速地从成骨前体细胞向成骨细胞分化，具有比聚乳酸更好的细胞相容性。
关键词：聚乳酸；改性；黏附性能；生物材料

郑丹芳，罗彦凤，向燕，王远亮.MC3T3-E1细胞在改性聚（DL-乳酸）表面的黏附性能[J].中国组织工程研究与临床康复，2008，12(10):1859-1862 [www.zglckf.com/zglckf/ejournal/upfiles/08-10/10k-1859(ps).pdf]

Adhesion of MC3T3-E1 cells to modified poly(DL-lactic acid)

Abstract

AIM：With the FDA certification, poly(DL-lactic acid) (PDLLA) is a kind of bio-degradable materials that can enter the human body, but its biocompatibility is relatively bad due to strong surface hydrophobicity and weak cellular affinity.
OBJECTIVE: To observe the adhesion of MC3T3-E1 osteoblastic progenitor cells to maleic anhydride-grafted PDLLA (MPLA) and tetramethylenediamine-grafted PDLLA (DPLA), evaluate the cytocompatibility of modified PDLLA, and compare with PDLLA.
DESIGN, TIME AND SETTING: A controlled trial was carried out in the Research Center of Bioinspired Material Science and Engineering, College of Bioengineering, Chongqing University in June 2007.
MATERIALS: PDLLA, MPLA and DPLA were all self-made; MC3T3-E1 cell strain was purchased from Shanghai Institute of Cell Biology.
METHODS: By means of in vitro culture, MC3T3-E1 cells were inoculated on PDLLA, MPLA and DPLA.
MAIN OUTCOME MEASURES: The influence of different substrate materials on MC3T3-E1 osteoblastic progenitor cells was detected through cell morphology, cell proliferation, cell cycle and cell adhesion.
RESULTS: The proliferation and adhesion of MC3T3-E1 osteoblastic progenitor cells on DPLA and MPLA were greater than those on PDLLA (P < 0.05); Cell cycle determination revealed that, DPLA and MPLA could promote the MC3T3-E1 osteoblastic progenitor cells from G0 phase to S phase and G2/M phase, and the cell morphology was more mature.
CONCLUSION: Modification of PDLLA by DPLA and MPLA can promote the adhesion and proliferation of MC3T3-E1 osteoblastic progenitor cells, and facilitate the differentiation from osteoblastic progenitor cells to osteoblasts with the better cytocompatibility than PDLLA.

Zheng DF, Luo YF, Xiang Y, Wang YL.Adhesion of MC3T3-E1 cells to modified poly(DL-lactic acid).Zhongguo Zuzhi Gongcheng Yanjiu yu Linchuang Kangfu 2008;12(10):1859-1862(China) [www.zglckf.com/zglckf/ejournal/upfiles/08-10/10k-1859(ps).pdf]