Agematsu K, Kobata T, Sugita K, Hirose T, Schlossman S F, Morimoto C
Division of Tumor Immunology, Dana-Farber Cancer Institute, Boston, MA, USA.
J Immunol. 1995 Apr 15;154(8):3627-35.
The engagement of CD27 with its ligand CD70 is considered to play an important role in T cell costimulation. In the present study, we investigated both the kinetics of CD70 expression and the contribution of its interaction with CD27 in T cell immune responses. CD70 was found to be expressed almost equally on both activated CD4 and CD8 T cells. On subsets of CD4 T cells, however, CD70 expression was induced preferentially on the CD45R0 T cell population after activation, whereas its expression was not noted on CD45RA T cells for almost 2 wk following activation. In long-term culture with media containing T cell growth factor (TCGF) and rIL-2, the expression of CD70 was increased markedly on CD45R0 T cells and minimally expressed on CD45RA T cells. In addition, strong surface expression of CD70 was observed on T cell clones originally derived from CD45R0+ CD4 T cells, whereas T cell clones originally derived from CD45RA+ CD4 T cells showed lower levels of expression. The addition of irradiated, activated CD45R0 T cells to CD45RA T cells caused a down-regulation of CD27 expression and an up-regulation of CD25 expression. These changes were blocked by addition of the anti-CD70 mAb, suggesting that direct contact between CD45R0 T cells and CD45RA T cells via CD27/CD70 occurred, leading to the activation of CD45RA T cells as measured by CD25 expression. These observations strongly support the notion that the engagement of CD27 plays an important regulatory role in the communication of subsets of CD45R0 and CD45RA T cells.
CD27与其配体CD70的结合被认为在T细胞共刺激中起重要作用。在本研究中，我们研究了CD70表达的动力学及其与CD27的相互作用在T细胞免疫反应中的作用。发现CD70在活化的CD4和CD8 T细胞上表达几乎相同。然而，在CD4 T细胞亚群中，活化后CD70优先在CD45R0 T细胞群体上诱导表达，而在活化后近2周内CD45RA T细胞上未观察到其表达。在含有T细胞生长因子（TCGF）和rIL-2的培养基中长期培养时，CD45R0 T细胞上CD70的表达明显增加，而在CD45RA T细胞上表达最低。此外，在最初源自CD45R0 + CD4 T细胞的T细胞克隆上观察到CD70的强表面表达，而最初源自CD45RA + CD4 T细胞的T细胞克隆显示较低水平的表达。将经辐照、活化的CD45R0 T细胞添加到CD45RA T细胞中导致CD27表达下调和CD25表达上调。这些变化被抗CD70单克隆抗体的添加所阻断，表明通过CD27 / CD70在CD45R0 T细胞和CD45RA T细胞之间发生了直接接触，导致通过CD25表达测量的CD45RA T细胞活化。这些观察结果有力地支持了CD27的结合在CD45R0和CD45RA T细胞亚群的通讯中起重要调节作用的观点。
