Conditional deletion reveals a cell-autonomous requirement of SLP-76 for thymocyte selection
Conditional deletion reveals a cell-autonomous requirement of SLP-76 for thymocyte selection
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DOI：
10.1084/jem.20051128
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发表时间：
2005-10-03
影响因子：
15.3
通讯作者：
Koretzky, GA
中科院分区：
文献类型：
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作者：
Maltzman, JS;Kovoor, L;Koretzky, GA
含有76 kD白细胞磷酸化蛋白（SLP-76）的SH2结构域对于tcr介导的胸腺CD4(+) CD8（+）双阳性（DP）阶段的成熟至关重要。SLP-76（null）小鼠在CD4(-) CD8(-) CD44(-) CD25(-)（双阴性3，DN3）阶段的绝对阻滞阻碍了我们对该接头在原发性胸腺细胞和外周T淋巴细胞中α - β tcr介导的信号转导中的作用的理解。为了评估在这些事件中对SLP-76的需求，我们使用了cre-loxP方法来生成在DN3检查点后有条件地删除SLP-76的小鼠。这些小鼠发育的DP胸腺细胞表面表达α - β TCR，但在基因组DNA和蛋白质水平上缺乏SLP-76。在年轻小鼠中，DP隔室的细胞数量减少，在体内不能对CD4（+）或CD8（+）单阳性（SP）细胞进行阳性选择，在体外也不能激活诱导细胞死亡。少量CD4(+) SP胸腺细胞生成，但这些细胞不能响应α - β tcr生成的信号来输送钙。外周T细胞数量减少，缺乏SLP-76蛋白，表面表型异常。这些研究首次表明，在T系原代细胞中，SLP-76是通过成熟的α - β TCR进行信号转导所必需的。
The SH2 domain containing leukocyte phosphoprotein of 76 kD (SLP-76) is critical for pre-TCR-mediated maturation to the CD4(+) CD8(+) double positive (DP) stage in the thymus. The absolute block in SLP-76(null) mice at the CD4(-) CD8(-) CD44(-) CD25(-) (double-negative 3, DN3) stage has hindered our understanding of the role of this adaptor in alpha beta TCR-mediated signal transduction in primary thymocytes and peripheral T lymphocytes. To evaluate the requirements for SLP-76 in these events, we used a cre-loxP approach to generate mice that conditionally delete SLP-76 after the DN3 checkpoint. These mice develop DP thymocytes that express the alpha beta TCR on the surface, but lack SLP-76 at the genomic DNA and protein levels. The DP compartment has reduced cellularity in young mice and fails to undergo positive selection to CD4(+) or CD8(+) single positive (SP) cells in vivo or activation-induced cell death in vitro. A small number of CD4(+) SP thymocytes are generated, but these cells fail to flux calcium in response to an alpha beta TCR-generated signal. Peripheral T cells are reduced in number, lack SLP-76 protein, and have an abnormal surface phenotype. These studies show for the first time that SLP-76 is required for signal transduction through the mature alpha beta TCR in primary cells of the T lineage.