Honda A, Raz A, Needleman P
Department of Biochemistry, Tokyo College of Pharmacy, Japan.
Biochem J. 1990 Nov 15;272(1):259-62. doi: 10.1042/bj2720259.
Cyclo-oxygenase (COX) production in human promyelocytic leukaemia (HL-60) cells was studied during monocytic differentiation induced by 1 alpha, 25-dihydroxyvitamin D3 (24 nM; 3 days) or phorbol 12-myristate 13-acetate (100 nM; 1 day), or during granulocytic differentiation induced by retinoic acid (1 microns; 4 days). Undifferentiated or differentiated HL-60 cells were labelled with [35S]methionine, and membrane-bound COX was solubilized and quantified by SDS/PAGE. Immunoprecipitated 35S-labelled COX from cells induced to differentiate into monocytic or granulocytic lineage were clearly detected on the autoradiograms as a protein of approx. 70 kDa molecular size, whereas only a very faint COX band was detected in untreated HL-60 cells. During both monocytic and granulocytic differentiation, COX activity (measured by the conversion of exogenous arachidonic acid into prostaglandin E2) was dramatically increased. In addition, thromboxane synthesis was preferentially enhanced during monocytic differentiation. HL-60 cells, induced to differentiate into the monocytic or granulocytic lineage, provide a useful tool to investigate the cellular mechanisms involved in regulation of the synthesis of individual prostanoid-metabolizing enzymes.
在人早幼粒细胞白血病（HL-60）细胞中，研究了1α,25-二羟基维生素D3（24 nM；3天）或佛波酯（100 nM；1天）诱导单核细胞分化过程中，以及视黄酸（1 μM；4天）诱导粒细胞分化过程中环氧合酶（COX）的产生情况。未分化或已分化的HL-60细胞用[35S]甲硫氨酸进行标记，膜结合的COX经十二烷基硫酸钠/聚丙烯酰胺凝胶电泳（SDS/PAGE）溶解并定量。在放射自显影片上，能清楚地检测到诱导分化为单核细胞或粒细胞系的细胞中免疫沉淀的35S标记的COX，其为一种分子大小约70 kDa的蛋白质，而在未处理的HL-60细胞中仅检测到一条非常微弱的COX条带。在单核细胞和粒细胞分化过程中，COX活性（通过将外源性花生四烯酸转化为前列腺素E2来测量）均显著增加。此外，在单核细胞分化过程中血栓素的合成优先增强。诱导分化为单核细胞或粒细胞系的HL-60细胞为研究参与调节个体前列腺素代谢酶合成的细胞机制提供了一个有用的工具。
