Nakamura S, Sung S S, Bjorndahl J M, Fu S M
Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City 73104.
J Exp Med. 1989 Mar 1;169(3):677-89. doi: 10.1084/jem.169.3.677.
A new mAb G38 was generated against purified EA 1, an early activation antigen. In immunoprecipitation, it was reactive with the same complex precipitated by the initial anti-EA 1 mAb P8. mAb G38 augmented PMA-induced proliferation of PBMC. It was shown to be mitogenic for purified T cells in collaboration with PMA in a dose-dependent manner. This effect was independent of monocytes and other accessory cells. mAb G38 augmented PMA-induced IL-2-R expression. In conjunction with PMA, it induced IL-2 synthesis and secretion. Its effects on IL-2-R and IL-2 expression were documented at both protein and mRNA levels. Both anti-EA 1 mAbs did not induce Ca2+ influx by themselves in PMA-treated T cells. However, the addition of second anti-mouse Ig antibodies induced readily detectable increases in [Ca2+]i. Ca2+-mediated pathways may be utilized as the transduction signal mechanisms. mAb Leu-23 was shown to be reactive with EA 1. mAb Leu-23 was also mitogenic for T cells in the presence of PMA. These findings provide evidence for a functional role for EA 1 in T cell activation and proliferation.
针对纯化的早期激活抗原EA 1产生了一种新的单克隆抗体G38。在免疫沉淀中，它与最初的抗EA 1单克隆抗体P8沉淀的相同复合物发生反应。单克隆抗体G38增强了佛波酯（PMA）诱导的外周血单个核细胞（PBMC）增殖。结果表明，在与PMA协同作用下，它对纯化的T细胞具有促有丝分裂作用，且呈剂量依赖性。这种作用不依赖于单核细胞和其他辅助细胞。单克隆抗体G38增强了PMA诱导的白细胞介素-2受体（IL-2-R）表达。与PMA一起，它诱导了IL-2的合成和分泌。其对IL-2-R和IL-2表达的影响在蛋白质和mRNA水平均得到证实。两种抗EA 1单克隆抗体本身在PMA处理的T细胞中均未诱导钙离子内流。然而，添加第二抗小鼠Ig抗体可诱导易于检测到的细胞内钙离子浓度（[Ca2+]i）升高。钙离子介导的途径可能被用作转导信号机制。单克隆抗体Leu-23被证明与EA 1发生反应。单克隆抗体Leu-23在有PMA存在的情况下对T细胞也具有促有丝分裂作用。这些发现为EA 1在T细胞激活和增殖中的功能作用提供了证据。
