Orthopaedic Clinic, Division for Biochemistry of Joint and Connective Tissue Diseases, University of Ulm, Oberer Eselsberg 45, D-89081 Ulm, Germany.
Int J Mol Med. 2011 Jan;27(1):139-45. doi: 10.3892/ijmm.2010.553. Epub 2010 Nov 10.
We have previously reported that star shaped poly(ethylene oxide-stat-propylene oxide) macromers with 80% EO content and isocyanate functional groups at the distal ends [NCO-sP(EO-stat-PO)] can be used to generate coatings that are non-adhesive but easily functionalized for specific cell adhesion. In the present study, we investigated whether the NCO-sP(EO-stat-PO) surfaces maintain peptide configuration-specific cell-surface interactions or if differences between dissimilar binding molecules are concealed by the coating. To this end, we have covalently immobilized both linear-RGD peptides (gRGDsc) and cyclic-RGD (RGDfK) peptides in such coatings. Subsequently, SaOS-2 or human multipotent mesenchymal stromal cells (MSC) were seeded on these substrates. Cell adhesion, spreading and survival was observed for up to 30 days. The time span for cell adherence was not different on linear and cyclic RGD peptides, but was shorter in comparison to the unmodified glass surface. MSC proliferation on cyclic RGDfK modified coatings was 4 times higher than on films functionalized by linear gRGDsc sequences, underlining that the NCO-sP(EO-stat-PO) film preserves the configuration-specific biochemical peptide properties. Under basal conditions, MSC expressed osteogenic marker genes after 14 days on cyclic RGD peptides, but not on linear RGD peptides or the unmodified glass surfaces. Our results indicate specific effects of these adhesion peptides on MSC biology and show that this coating system is useful for selective testing of cellular interactions with adhesive ligands.
我们之前曾报道过，具有 80%EO 含量和末端异氰酸酯官能团的星形聚（氧化乙烯-丙二醇）大分子单体[NCO-sP(EO-stat-PO)]可用于生成非粘性但易于功能化的涂层，以实现特定细胞的粘附。在本研究中，我们研究了 NCO-sP(EO-stat-PO)表面是否保持肽构象特异性的细胞表面相互作用，或者不同结合分子之间的差异是否被涂层掩盖。为此，我们已经将线性-RGD 肽（gRGDsc）和环状-RGD（RGDfK）肽共价固定在这些涂层中。随后，将 SaOS-2 或人多能间充质基质细胞（MSC）接种在这些基质上。观察细胞粘附、铺展和存活长达 30 天。线性和环状 RGD 肽上细胞黏附的时间间隔没有差异，但与未修饰的玻璃表面相比，时间间隔更短。在环 RGDfK 修饰的涂层上，MSC 的增殖是线性 gRGDsc 序列功能化膜的 4 倍，这表明 NCO-sP(EO-stat-PO)膜保留了构象特异性的生化肽特性。在基础条件下，MSC 在环状 RGD 肽上培养 14 天后表达成骨标记基因，但在线性 RGD 肽或未修饰的玻璃表面上则没有表达。我们的结果表明这些粘附肽对 MSC 生物学具有特异性影响，并表明这种涂层系统可用于选择性测试细胞与粘附配体的相互作用。
