IL-7 maintains the T cell precursor potential of CD3-CD4-CD8- thymocytes.
IL-7 maintains the T cell precursor potential of CD3-CD4-CD8- thymocytes.
复制标题
IL-7维持CD3-CD4-CD8-胸腺细胞的T细胞前体潜能。
作者：
T. Suda;A. Zlotnik
我们和其他研究者报道了IL-4（在PMA存在下）或IL-7（单独使用）诱导成人和胎儿（妊娠第15天）CD 4-CD 8-胸腺细胞增殖。这些结果表明，这些细胞因子可能是前T细胞的生长因子。然而，我们最近观察到，在成人CD 4-CD 8-胸腺细胞，只有CD 3+亚群增殖响应IL-7，而IL-4 + PMA诱导CD 3-和CD 3+亚群的增殖反应。因此，我们得出结论，单独使用IL-7不是成人胸腺CD 3-CD 4-CD 8-三阴性（TN）T细胞前体的有效生长刺激。有趣的是，成人TN胸腺细胞在培养中的生存能力提高IL-7长达1周，尽管IL-7不能诱导显着的[3 H]TdR掺入这些细胞。在IL-7中培养4天后，活细胞保持CD 4-CD 8-，但25 - 35%表达CD 3，而其余保持CD 3-。相反，用IL-4 + PMA培养4天的大多数细胞仍保持TN。为了研究在IL-4 + PMA或IL-7存在下体外存活的成人TN胸腺细胞是否保留T细胞祖细胞潜能，我们测试了它们是否可以重建淋巴细胞耗尽（2-脱氧鸟苷处理）的胎儿胸腺器官培养物。我们的结果表明，TN细胞培养在IL-7保留T细胞祖细胞的潜力。
We and other investigators have reported that IL-4 (in the presence of PMA) or IL-7 (used alone) induce proliferation of both adult and fetal (gestation day 15) CD4-CD8- thymocytes. These results suggested that these cytokines may be growth factors for pre-T cells. However, we recently observed that among adult CD4-CD8- thymocytes, only the CD3+ subset proliferates in response to IL-7, whereas IL-4 + PMA induces proliferative responses in both CD3- and CD3+ subsets. Thus, we concluded that IL-7 used alone is not a potent growth stimulus for adult thymic CD3-CD4-CD8- triple negative (TN) T cell precursors. Interestingly, the viability of adult TN thymocytes in culture was improved by IL-7 for up to 1 wk, in spite of the inability of IL-7 to induce significant [3H]TdR incorporation in these cells. After culture in IL-7 for 4 days, the viable cells remained CD4-CD8-, but 25 to 35% expressed CD3 whereas the rest remained CD3-. In contrast, most of the cells cultured with IL-4 + PMA for 4 days remained TN. To investigate whether adult TN thymocytes that survive in vitro in the presence of IL-4 + PMA or IL-7 retain T cell progenitor potential, we tested whether they could reconstitute lymphoid cell-depleted (2-deoxyguanosine-treated) fetal thymus organ cultures. Our results demonstrate that TN cells cultured in IL-7 retain T cell progenitor potential.