Wright C D, Stewart S F, Kuipers P J, Hoffman M D, Devall L J, Kennedy J A, Ferin M A, Thueson D O, Conroy M C
Immunopathology Department, Parke-Davis Pharmaceutical Research Division, Warner-Lambert Company, Ann Arbor, Michigan 48105.
J Leukoc Biol. 1994 Apr;55(4):443-51. doi: 10.1002/jlb.55.4.443.
The cell activation inhibitor CI-959 [5-methoxy-3-(1-methylethoxy)-N-1H-tetrazol-5-ylbenzo[ b]thiophene-2- carboxamide, monosodium salt] was evaluated for its effects on human neutrophil functions. CI-959 inhibited spontaneous migration and chemotaxis toward N-formyl-methionyl-L-leucyl-L-phenylalanine (fMLP) with 50% inhibition (IC50) values of 3.6 and 3.1 microM, respectively. CI-959 also inhibited superoxide anion generation in response to C5a, fMLP, serum-opsonized zymosan (SOZ), concanavalin A (Con A), and calcium ionophore A23187 with IC50 values of 2.5, 4.7, 14.5, 5.4, and 14.8 microM, respectively. In comparison, CI-959 inhibited myeloperoxidase microM, respectively. In comparison, CI-959 inhibited myeloperoxidase release in response to C5a, fMLP, SOZ, and Con A with IC50 values of 11.6, 16.1, 7.5, and < 1.0 microM, respectively, while inhibiting the response to A23187 by only 5.5% at 100 microM. At concentrations up to 100 microM, CI-959 had no effect on the respiratory burst or degranulation in response to L-alpha-1,2-dioctanoylglycerol (DiC8) or phorbol 12-myristate 13-acetate (PMA). In addition, the compound inhibited leukotriene B4 release stimulated by fMLP and SOZ (IC50 values 4.0 and 2.5 microM, respectively), while having less activity against the A23187-stimulated response (IC50 > 100 microM). These results demonstrate that CI-959 inhibits cellular responses to stimuli that mobilize intracellular calcium. For cellular responses to inophore-mediated calcium influx, only oxygen radical production was inhibited by CI-959. CI-959 was further evaluated for its effects on neutrophil stimulus-response coupling. At 100 microM, CI-959 had no effect on human neutrophil phospholipase C or protein kinase C. CI-959 inhibited fMLP-stimulated intracellular calcium mobilization and calcium influx with IC50 values of 16.7 and 3.1 microM, respectively, and exhibited less potent calmodulin antagonist activity (IC50 = 90.5 microM). These results indicate that CI-959 may exert its stimulus- and response-specific inhibitory effects on neutrophil functions, in part, through inhibition of calcium-regulated signalling mechanisms.
对细胞激活抑制剂CI-959 [5-甲氧基-3-(1-甲基乙氧基)-N-(1H-四氮唑-5-基)苯并[b]噻吩-2-甲酰胺单钠盐] 对人中性粒细胞功能的影响进行了评估。CI-959抑制自发迁移以及对N-甲酰甲硫氨酰-L-亮氨酰-L-苯丙氨酸（fMLP）的趋化作用，其50%抑制（IC50）值分别为3.6和3.1微摩尔。CI-959还抑制对C5a、fMLP、血清调理酵母聚糖（SOZ）、伴刀豆球蛋白A（Con A）和钙离子载体A23187的超氧阴离子生成，其IC50值分别为2.5、4.7、14.5、5.4和14.8微摩尔。相比之下，CI-959抑制对C5a、fMLP、SOZ和Con A的髓过氧化物酶释放，IC50值分别为11.6、16.1、7.5和<1.0微摩尔，而在100微摩尔时对A23187刺激的反应仅抑制5.5%。在浓度高达100微摩尔时，CI-959对L-α-1,2-二辛酰甘油（DiC8）或佛波醇12-肉豆蔻酸酯13-乙酸酯（PMA）刺激的呼吸爆发或脱颗粒无影响。此外，该化合物抑制fMLP和SOZ刺激的白三烯B4释放（IC50值分别为4.0和2.5微摩尔），而对A23187刺激的反应活性较低（IC50>100微摩尔）。这些结果表明，CI-959抑制细胞对动员细胞内钙的刺激的反应。对于离子载体介导的钙内流引起的细胞反应，CI-959仅抑制氧自由基的产生。进一步评估了CI-959对中性粒细胞刺激-反应偶联的影响。在100微摩尔时，CI-959对人中性粒细胞磷脂酶C或蛋白激酶C无影响。CI-959抑制fMLP刺激的细胞内钙动员和钙内流，IC50值分别为16.7和3.1微摩尔，并表现出较弱的钙调蛋白拮抗剂活性（IC50 = 90.5微摩尔）。这些结果表明，CI-959可能部分通过抑制钙调节信号机制，对中性粒细胞功能发挥其刺激和反应特异性抑制作用。
