Rich B E, Leder P
Department of Genetics, Harvard Medical School, Boston, Massachusetts.
J Exp Med. 1995 Mar 1;181(3):1223-8. doi: 10.1084/jem.181.3.1223.
The thymic lesion of the nude mouse causes a profound block in T cell development. The failure of most T cells to mature in nude mice is likely to reflect a requirement for signals elaborated in the normal thymus. Interleukin 7 (IL-7), a lymphokine that is normally expressed in the thymus and has been implicated in T cell maturation, might be central to this process. To test this possibility, we introduced a transgene directing lymphoid expression of IL-7 into nude mice and found that it substantially alleviates the block in T cell maturation caused by the thymic defect. IL-7 transgenic nude mice have increased numbers of peripheral cells expressing the T cell marker Thy-1, the T cell antigen receptor complex, and the co-receptors CD4 and CD8. The IL-7 transgene also restores T cell-specific proliferation and activation responses to the peripheral cells of transgene-rescued nude mice. Such findings point toward a fundamental role for IL-7 in the thymic maturation of T cells.
裸鼠的胸腺病变导致T细胞发育严重受阻。大多数T细胞在裸鼠体内无法成熟，这可能反映出正常胸腺中产生的信号的必要性。白细胞介素7（IL-7）是一种通常在胸腺中表达且与T细胞成熟有关的淋巴因子，可能是这一过程的核心。为了验证这一可能性，我们将一个指导IL-7在淋巴细胞中表达的转基因导入裸鼠体内，发现它能显著缓解胸腺缺陷导致的T细胞成熟受阻。IL-7转基因裸鼠外周表达T细胞标志物Thy-1、T细胞抗原受体复合物以及共受体CD4和CD8的细胞数量增加。IL-7转基因还恢复了转基因拯救的裸鼠外周细胞的T细胞特异性增殖和激活反应。这些发现表明IL-7在T细胞的胸腺成熟过程中具有重要作用。
