Aramburu J, Balboa M A, Rodríguez A, Melero I, Alonso M, Alonso J L, López-Botet M
Sección de Inmunología, Hospital de la Princesa, Madrid, Spain.
J Immunol. 1993 Oct 1;151(7):3420-9.
We have previously described that a mAb directed against a surface dimer (Kp43) expressed by NK cells was able to regulate cell proliferation, enhance the cytotoxicity of IL-2-activated NK cells, and activate phospholipase D. In this work we have analyzed the ability of the anti-Kp43 mAb to regulate the production of TNF-alpha. Our results show that the stimulation of IL-2-activated NK cells with soluble anti-Kp43 mAb or its F(ab')2 activated the secretion of the cytokine, inasmuch as this effect is associated with the induction of cellular aggregation. The intensity of the Kp43-mediated stimulation varied among different IL-2-activated NK cell samples. Even in those instances where the anti-Kp43 mAb alone could not detectably enhance TNF-alpha production, it displayed a synergistic effect combined to a soluble anti-CD16 mAb, which on its own did not efficiently activate cytokine production. The anti-Kp43 mAb also cooperated with a phorbol ester, although it did not modify the TNF-alpha production triggered by a Ca2+ ionophore. The anti-Kp43-mediated effect, which required the preactivation of cells with IL-2, was inhibited by cycloheximide and actinomycin D and was associated with an increase in the levels of TNF-alpha-specific mRNA. It is noteworthy that the Kp43-mediated production of TNF-alpha was partially inhibited by anti-CD18, anti-CD11a and anti-ICAM-1 mAb that blocked LFA-1-dependent cellular interactions, which impaired NK cell aggregation and, moreover, was dependent on the presence of extracellular Mg2+, thus suggesting that the leukocyte integrin is involved in the activation process triggered through Kp43.
我们之前曾描述过，一种针对自然杀伤细胞（NK细胞）表面二聚体（Kp43）的单克隆抗体（mAb）能够调节细胞增殖，增强白细胞介素2（IL-2）激活的NK细胞的细胞毒性，并激活磷脂酶D。在这项研究中，我们分析了抗Kp43 mAb调节肿瘤坏死因子-α（TNF-α）产生的能力。我们的结果表明，用可溶性抗Kp43 mAb或其F(ab')2刺激IL-2激活的NK细胞可激活细胞因子的分泌，因为这种效应与细胞聚集的诱导有关。Kp43介导的刺激强度在不同的IL-2激活的NK细胞样本中有所不同。即使在单独使用抗Kp43 mAb无法检测到增强TNF-α产生的情况下，它与可溶性抗CD16 mAb联合使用时也显示出协同效应，而抗CD16 mAb单独使用时不能有效地激活细胞因子的产生。抗Kp43 mAb也与佛波酯协同作用，尽管它不会改变由钙离子载体触发的TNF-α产生。抗Kp43介导的效应需要用IL-2对细胞进行预激活，该效应被放线菌酮和放线菌素D抑制，并且与TNF-α特异性mRNA水平的增加有关。值得注意的是，Kp43介导的TNF-α产生被抗CD18、抗CD11a和抗细胞间黏附分子-1（ICAM-1）mAb部分抑制，这些抗体阻断了淋巴细胞功能相关抗原-1（LFA-1）依赖性细胞相互作用，这损害了NK细胞聚集，此外，该效应还依赖于细胞外镁离子的存在，因此表明白细胞整合素参与了通过Kp43触发的激活过程。
