摘要
目的 研究巨噬细胞表面apoE的特性及与脂蛋白代谢的关系，以进一步了解巨噬细胞在动脉粥样硬化发展过程中的作用。方法 以抗apoE单克隆抗体（7C9，3H1）的特异性结合，分析乙酰LDL、肝素及硫酸软骨素酶、LiposynⅡ等因素对THP-2细胞表面apoE的影响及相互关系。结果 经乙酰LDL作用后，在4℃时125I-7C9与细胞表面结合减少19%；而去除乙酰LDL后再37℃孵育2 h可增加结合25%。与乙酰LDL孵育可使细胞分泌至培养液中的apoE增加，并且呈时间依赖。肝素酶（3 U/ml）或硫酸软骨素酶ABC（0．75 U/ml）对未经乙酰LDL作用的THP-1细胞表面的apoE没有影响，对经乙酰LDL作用后的细胞肝素酶有轻微影响（与7C9结合下降7．9%），而硫酸软骨素酶孵育可使细胞表面apoE下降50%。LiposynⅡ可显著增加apoA1与THP1细胞表面的结合，增加的结合面可通过预先与3H1单抗孵育而被拮抗。结论 THP-1巨噬细胞表面apoE与细胞摄取胆固醇的过程及细胞表面的蛋白多糖代谢均有密切关系，可能还参与了apoA1脂质体与THP-1细胞表面结合过程，它们的相互作用可能会影响巨噬细胞的脂质代谢功能，进而可能对动脉粥样硬化的发展产生影响。
Objective To study the characterization of THP-1 cell surface apoE in order to learn the further role of macrophage in development of atherosclerosis． Methods Using monoclonal antibodies (7C9,3H1)against apoE to analyze the effects of AcLDL, heparin, chondroitinase, and Liposyn Ⅱ on the apoE of THP-1 cell surface． Results Cholesterol(AcLDL)loaded cell demonstrated reduced binding of 125I-7C9 to the cell surface by 19% at 4℃, but if the THP-1 cell incubated at 37℃ for 2 hours after the removal of AcLDL there was a increase(25%)in 7C9 bound to loaded cells when compared to the 4℃ controls； prior loading with AcLDL also increased the secretion of apoE to the extracellular medium in a time-dependent manner； heparinase or chondroitinase ABC did not reduce the surface apoE associated with unloaded cells； the apoE on the surface of loaded macrophage was only marginally affected(9．3%)by incubation with heparinase but was efficiently reduced(50%)by incubation with chondroitinase ABC； Liposyn Ⅱ dramatically increased the binding of apoA1 to the cell surface(1．5 ～ 1．8 fold), the Liposyn Ⅱ mediated increased binding of apoA1 was antagonized by pre-incubation of THP-1 cells with 3H1 indicating that it was an apoE-dependent process． Conclusions Cell surface apoE of THP-1 macrophage relates to the process of cholesterol loading of macrophage cells and lipid mediated binding of apoA1 to the cell surface． It may affect the process of atherosclerosis development．
出处
《中国医学科学院学报》
CAS
CSCD
北大核心
2001年第4期337-340,共4页
Acta Academiae Medicinae Sinicae
