PHBHHx膜表面亲水改性及其与神经干细胞生物相容性

Biocompatibility of surface modified PHBHHx with rat embryonic neural stem cells

对羟基丁酸-羟基己酸共聚酯(PHBHHx)膜进行表面改性,研究神经干细胞(NSCs)在改性后的PHBHHx膜表面的贴附、增殖及分化情况,为开发新型脑组织工程支架材料奠定基础。采用溶剂挥发法制备PHBHHx膜,扫描电镜观察其表面性状;分别通过脂肪酶处理,NaOH处理的方法对PHBHHx膜进行表面改性,测量接触角以检测膜表面亲水性。分离培养孕14.5 d大鼠胚胎大脑皮质NSCs,接种在表面改性后的PHBHHx膜表面进行体外培养,扫描电镜观察膜表面细胞形态,MTT法检测细胞活力,免疫细胞化学染色观察NSCs存活和分化情况。结果显示,与未处理的PHBHHx膜相比,脂肪酶、NaOH处理能够显著提高PHBHHx膜表面亲水性,增加NSCs在PHBHHx膜表面贴附数量;NSCs在改性后的PHBHHx膜表面能够良好地存活并分化为神经元和胶质细胞。结果提示PHBHHx膜表面碱处理通过提高材料表面亲水性和粗糙程度,增加其与NSCs的生物相容性,改性后的PHBHHx材料是一种非常有潜力的新型脑组织工程支架材料,有望在NSCs移植修复脑损伤中发挥作用。

To study the attachment, proliferation and differenciation of neural stem cells （NSCs） on surface modified PHBHHx films and to establish the theory of PHBHHx application in NSCs-based brain tissue engineering. PHBHHx film was fabricated by a solution-casting method, and the morphology of the ？lm was observed under scanning electron microscopy（SEM）. The films were treated by NaOH or lipase, then the surface hydrophilic property was characterized using water contact angle measurement. NSCs were isolated from the cerebral cortex of rat embryos on embryonic day 14.5, and cultured on surface treated PHBHHx films. The morphology of NSCs attached on the film was visualized under SEM, and the survival and differentiation of NSCs were observed through immunocytochemical staining. Compared with the untreated PHBHHx films, the water contact angle of NaOH or lipase treated PHBHHx films decreased dramatically, and the number of NSCs attached significantly increased. NSCs survived well on treated PHBHHx films and differentiated into neurons and glial cells. The amelioration of hydrophilic property of PHBHHx film improved its biocompatibility with NSCs. PHBHHx can serve as a novel CNS tissue engineering biomaterial applied for NSCs transplantation, brain repairing and regeneration.