Dilloo D, Dirksen U, Schneider M, Zessack N, Buttlies B, Levitt L, Burdach S
Department of Pediatric Hematology/Oncology, Heinrich-Heine University Medical Center, Dusseldorf, Germany.
Exp Hematol. 1996 Mar;24(4):537-43.
Interleukin-3 (IL-3) is expressed in T lymphocytes and stimulates the growth of multipotent hematopoietic progenitors. Little is known, however, about the stimuli that lead to IL-3 protein release. We examined IL-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF) mRNA expression and protein secretion in human T lymphocytes following activation via the TCR/CD3 complex, the CD2 receptor, and the IL-2 receptor. GM-CSF mRNA expression and protein release were found in CD3 and CD2 activated T cells with maximum GM-CSF release following stimulation with IL-2. IL-3 protein release is regulated via the CD2 receptor with virtually no IL-3 release after T cell stimulation via CD3. In contrast, IL-3 mRNA accumulation is more pronounced after CD3 activation than after CD2 activation. This suggests that upregulation of IL-3 protein release following T cell stimulation via CD-2 occurs largely at the translational or posttranslational level. These data also indicate that differential control of cytokine production can occur in response to activation of the alternative T cell receptor. Interaction of the T cell CD2-receptor with its natural ligand LFA-3 expressed on stromal cells might represent a regulatory mechanism for rapid release of IL-3, facilitating proliferation of multipotent hematopoietic cells.
白细胞介素-3（IL-3）在T淋巴细胞中表达，并刺激多能造血祖细胞的生长。然而，关于导致IL-3蛋白释放的刺激因素知之甚少。我们检测了经TCR/CD3复合物、CD2受体和IL-2受体激活后的人T淋巴细胞中IL-3和粒细胞-巨噬细胞集落刺激因子（GM-CSF）的mRNA表达及蛋白分泌情况。在CD3和CD2激活的T细胞中发现了GM-CSF的mRNA表达和蛋白释放，用IL-2刺激后GM-CSF释放量最大。IL-3蛋白释放通过CD2受体调节，经CD3刺激T细胞后几乎没有IL-3释放。相反，CD3激活后IL-3 mRNA的积累比CD2激活后更明显。这表明经CD-2刺激T细胞后IL-3蛋白释放的上调主要发生在翻译或翻译后水平。这些数据还表明，针对替代性T细胞受体的激活，细胞因子产生的差异控制可能会发生。T细胞CD2受体与其在基质细胞上表达的天然配体LFA-3的相互作用可能代表了一种快速释放IL-3的调节机制，有助于多能造血细胞的增殖。
