LIPOPROTEIN-LIPASE ENHANCES BINDING OF LIPOPROTEINS TO HEPARAN-SULFATE ON CELL-SURFACES AND EXTRACELLULAR-MATRIX
LIPOPROTEIN-LIPASE ENHANCES BINDING OF LIPOPROTEINS TO HEPARAN-SULFATE ON CELL-SURFACES AND EXTRACELLULAR-MATRIX
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DOI：
10.1172/jci116081
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发表时间：
1992-11-01
影响因子：
15.9
通讯作者：
VLODAVSKY, I
中科院分区：
文献类型：
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作者：
EISENBERG, S;SEHAYEK, E;VLODAVSKY, I
脂蛋白脂肪酶在4℃时增强人血浆脂蛋白（乳糜微粒、VLDL、中密度脂蛋白、LDL和HDL3）与培养成纤维细胞、hepG-2细胞和细胞外基质的结合。肝素酶处理细胞和基质可使脂蛋白-脂肪酶增强结合减少90-95%。脂蛋白脂肪酶对脂蛋白与硫酸肝素缺乏突变体中国仓鼠卵巢细胞的结合影响很小，而促进与野生型细胞的结合，肝素酶处理后这种结合被消除。对于I-125-LDL，脂蛋白脂肪酶也能增强正常人皮肤成纤维细胞在37℃下的摄取和蛋白水解降解，但对肝素酶处理的正常细胞或LDL受体阴性成纤维细胞没有影响。这些观察结果证明，脂蛋白脂肪酶主要导致脂蛋白在细胞表面和细胞外基质中与硫酸肝素结合，而不是与受体结合。这种相互作用使脂蛋白与细胞表面接近，并可能促进发生在细胞表面的代谢事件，包括促进向细胞受体的转移。
Lipoprotein lipase enhances binding at 4-degrees-C of human plasma lipoproteins (chylomicrons, VLDL, intermediate density lipoprotein, LDL, and HDL3) to cultured fibroblasts and hepG-2 cells and to extracellular matrix. Heparinase treatment of cells and matrix reduces the lipoprotein lipase enhanced binding by 90-95%. Lipoprotein lipase causes only a minimal effect on the binding of lipoproteins to heparan sulfate deficient mutant Chinese hamster ovary cells while it promotes binding to wild type cells that is abolished after heparinase treatment. With I-125-LDL, lipoprotein lipase also enhances uptake and proteolytic degradation at 37-degrees-C by normal human skin fibroblasts but has no effect in heparinase-treated normal cells or in LDL receptor-negative fibroblasts. These observations prove that lipoprotein lipase causes, predominantly, binding of lipoproteins to heparan sulfate at cell surfaces and in extracellular matrix rather than to receptors. This interaction brings the lipoproteins into close proximity with cell surfaces and may promote metabolic events that occur at the cell surface, including facilitated transfer to cellular receptors.