Poly(D,L-lactic acid)-poly(ethylene glycol)-monomethyl ether diblock copolymers control adhesion and osteoblastic differentiation of marrow stromal cells
Poly(D,L-lactic acid)-poly(ethylene glycol)-monomethyl ether diblock copolymers control adhesion and osteoblastic differentiation of marrow stromal cells
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DOI：
10.1089/107632703762687555
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发表时间：
2003-02-01
影响因子：
--
通讯作者：
Schulz, MB
中科院分区：
文献类型：
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作者：
Lieb, E;Tessmar, J;Schulz, MB
生物可降解聚合物，如聚乳酸（PLA）和聚乳酸-乙醇酸共聚物（PLGA），是有吸引力的组织工程材料，因为它们的降解和机械性能，这使得支架可以定制不同组织的个性化需求。虽然这些材料支持组织发育，但它们的化学性质不能控制细胞粘附或功能，因为当材料与体液接触时，它们的表面立即被吸附的血清蛋白所掩盖。此外，粘附蛋白在吸附到疏水性材料如PLA时经历构象变化和生物活性降低。为了克服这些局限性，我们修改了PLA的性能，通过合成一个二嵌段共聚物与聚（乙二醇）（PEG），这是已知的，以减少吸附的蛋白质的量，并修改其构象。通过改变这些二嵌段共聚物的PEG含量，我们能够控制粘附蛋白的吸附，并且由于细胞粘附仅在血清蛋白存在下发生，因此能够控制细胞粘附和细胞形状。与PLA、PLGA和组织培养聚苯乙烯相比，PEG-PLA显著改善了骨髓基质细胞向成骨细胞表型的分化，并导致碱性磷酸酶活性和矿化增加2倍。
Biodegradable polymers, such as poly( lactic acid) (PLA) and poly( lactic-coglycolic acid) (PLGA), are attractive materials for tissue engineering because of their degradative and mechanical properties, which permit scaffolds to be tailored to the individual requirements of different tissues. Although these materials support tissue development, their chemical properties offer no control of cell adhesion or function because their surfaces become immediately masked by adsorbing serum proteins when the materials come into contact with body fluids. Furthermore, adhesion proteins undergo conformational changes and a decrease in bioactivity when adsorbed to hydrophobic materials, such as PLA. To overcome these limitations, we modified the properties of PLA by synthesizing a diblock copolymer with poly( ethylene glycol) (PEG), which is known to reduce the amount of adsorbed proteins and to modify their conformation. By altering the PEG content of these diblock copolymers we were able to control the adsorption of adhesion proteins and, because cell adhesion takes place only in the presence of serum proteins, to control cell adhesion and cell shape. Marrow stromal cell differentiation to the osteoblastic phenotype was strongly improved on PEG-PLA compared with PLA, PLGA and tissue culture polystyrene and led to a 2-fold increase in alkaline phosphatase activity and mineralization.