Mahoney E M, Khoo J C, Steinberg D
Proc Natl Acad Sci U S A. 1982 Mar;79(5):1639-42. doi: 10.1073/pnas.79.5.1639.
Human peripheral blood monocytes and rabbit alveolar macrophages secreted lipoprotein lipase during culture. Within hours after plating, lipoprotein lipase had accumulated in the culture medium of monocytes, and the rate of accumulation increased with time in culture. The initial rate of secretion of lipoprotein lipase by alveolar macrophages was higher than in monocytes but decreased after 8--10 hr to values similar to those expressed by monocytes cultured for the same length of time. The enzyme was characterized as lipoprotein lipase (triacylglycero-protein acylhydrolase, EC 3.1.1.34) on the basis of pH optimum (7.8--8.2 for monocytes, 8.1 for alveolar macrophages), dependence on apolipoprotein C-II for activity, inhibition by 0.3--0.5 M sodium chloride and protamine sulfate, and retention of a heparin-Sepharose gel. The expression of lipoprotein lipase secretion by human monocytes may have important implications with respect to the development of foam cells in the arterial wall during atherogenesis.
人外周血单核细胞和兔肺泡巨噬细胞在培养过程中分泌脂蛋白脂肪酶。接种后数小时内,脂蛋白脂肪酶在单核细胞的培养基中积累,且积累速率随培养时间增加。肺泡巨噬细胞分泌脂蛋白脂肪酶的初始速率高于单核细胞,但在8 - 10小时后下降至与相同培养时间的单核细胞所表达的值相似。基于最适pH(单核细胞为7.8 - 8.2,肺泡巨噬细胞为8.1)、对载脂蛋白C-II的活性依赖性、0.3 - 0.5 M氯化钠和硫酸鱼精蛋白的抑制作用以及在肝素-琼脂糖凝胶上的保留情况,该酶被鉴定为脂蛋白脂肪酶(三酰甘油-蛋白酰基水解酶,EC 3.1.1.34)。人单核细胞脂蛋白脂肪酶分泌的表达可能对动脉粥样硬化形成过程中动脉壁泡沫细胞的发展具有重要意义。