Complexing of the CD-3 subunit by a monoclonal antibody activates a microtubule-associated protein 2 (MAP-2) serine kinase in Jurkat cells.
Complexing of the CD-3 subunit by a monoclonal antibody activates a microtubule-associated protein 2 (MAP-2) serine kinase in Jurkat cells.
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单克隆抗体与 CD-3 亚基的复合可激活 Jurkat 细胞中的微管相关蛋白 2 (MAP-2) 丝氨酸激酶。
DOI：
10.1042/bj2620449
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Landreth,G
中科院分区：
文献类型：
--
作者：
Hanekom,C;Nel,A;Gittinger,C;Rheeder,A;Landreth,G
用抗CD-3单克隆抗体处理Jurkat T细胞导致丝氨酸激酶的快速和瞬时活化，所述丝氨酸激酶利用微管相关蛋白MAP-2作为体外底物。该激酶也被激活的Jurkat细胞与植物血凝素治疗，但具有不同的时间过程。抗CD-3抗体对MAP-2激酶的激活呈剂量依赖性，在大于500 ng/ml的浓度下观察到最大活性。正常人E玫瑰花结阳性T细胞在抗CD-3治疗期间也表现出MAP-2激酶活性的诱导。该酶是最佳的活性在2 mM-Mn 2+的存在下，较低水平的活性与Mg 2+，即使在浓度高达20 mM。该激酶部分纯化通过DE-52 Sephacel与活性洗脱为一个单一的峰在0.25 M-NaCl。通过凝胶过滤估计分子量为45 kDa。MAP-2激酶的活化可能是由于该酶的磷酸化，因为用碱性磷酸酶处理降低了其活性。这些数据表明，通过CD-3复合物刺激T细胞导致一种新的丝氨酸激酶的活化，这种激酶可能在这些细胞的信号转导中起关键作用。
Treatment of Jurkat T-cells with anti-CD-3 monoclonal antibodies resulted in the rapid and transient activation of a serine kinase which utilized the microtubule-associated protein, MAP-2, as a substrate in vitro. The kinase was also activated on treatment of Jurkat cells with phytohaemagglutinin, but with a different time course. The activation of the MAP-2 kinase by anti-CD-3 antibodies was dose-dependent, with maximal activity observed at concentrations of greater than 500 ng/ml. Normal human E-rosette-positive T-cells also exhibited induction of MAP-2 kinase activity during anti-CD-3 treatment. The enzyme was optimally active in the presence of 2 mM-Mn2+; lower levels of activity were observed with Mg2+, even at concentrations up to 20 mM. The kinase was partially purified by passage over DE-52 Sephacel with the activity eluting as a single peak at 0.25 M-NaCl. The molecular mass was estimated to be 45 kDa by gel filtration. The activation of the MAP-2 kinase was probably due to phosphorylation of this enzyme as treatment with alkaline phosphatase diminished its activity. These data demonstrate that the stimulation of T-cells through the CD-3 complex results in the activation of a novel serine kinase which may be critically involved in signal transduction in these cells.