Division of Biomedical Engineering, Research Institute, National Defense Medical College, Tokorozawa, Saitama, Japan.
J Biomed Mater Res B Appl Biomater. 2010 Jan;92(1):32-9. doi: 10.1002/jbm.b.31486.
Fragmin (low-molecular-weight heparin)/protamine microparticles (F/P MPs) immobilize to culture plates, thereby retaining the binding of heparin-binding cytokines such as human stem cell factor (SCF). The purpose of this study was to evaluate the ability of F/P MP-coating to immobilize, stabilize, and enhance SCF-activity. Cell assays showed that SCF and preimmobilized SCF on F/P MP-coated plates significantly stimulated the proliferation of human erythroleukemia cell line TF-1 in a concentration-dependent manner. Heparin and fragmin enhanced SCF-induced proliferation of chlorate-treated TF-1 cells, in which the biosynthesis of endogenous sulfated polysaccharides was blocked, on noncoated plates at a range of concentrations (2-8 microg/mL). However, heparin and fragmin had no effect on SCF-induced proliferation of chlorate-treated TF-1 cells on F/P MP-coated plates. The interaction of SCF with fragmin and F/P MPs prolonged the half-life of SCF bioactivity, and immobilized and protected SCF from inactivation, such as from heat and proteolysis. These results suggest that F/P MP-coated plates protect SCF and enhance its activity, and F/P MP-coating provides an excellent biomaterial to immobilize and retain heparin-binding cytokines, including SCF, in bioactive form for optimal expansion of hematopoietic cells.
Fragmin（低分子量肝素）/鱼精蛋白微球（F/P MPs）固定在培养板上，从而保留肝素结合细胞因子（如人干细胞因子（SCF））的结合。本研究的目的是评估 F/P MP 涂层固定、稳定和增强 SCF 活性的能力。细胞实验表明，SCF 和预先固定在 F/P MP 涂层板上的 SCF 以浓度依赖的方式显著刺激人红白血病细胞系 TF-1 的增殖。肝素和低分子肝素在非涂层板上以 2-8 μg/mL 的浓度增强了氯化物处理的 TF-1 细胞中 SCF 诱导的增殖，其中内源性硫酸多糖的生物合成被阻断。然而，肝素和低分子肝素对氯化物处理的 TF-1 细胞在 F/P MP 涂层板上的 SCF 诱导的增殖没有影响。SCF 与鱼精蛋白和 F/P MPs 的相互作用延长了 SCF 生物活性的半衰期，并固定和保护 SCF 免受失活，如热和蛋白水解。这些结果表明，F/P MP 涂层板保护 SCF 并增强其活性，并且 F/P MP 涂层提供了一种极好的生物材料，可将包括 SCF 在内的肝素结合细胞因子以生物活性形式固定并保留，以实现最佳的造血细胞扩增。
