Single-cell analyses reveal two defects in peptide-specific activation of naive T cells from aged mice
Single-cell analyses reveal two defects in peptide-specific activation of naive T cells from aged mice
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DOI：
10.4049/jimmunol.166.5.3151
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发表时间：
2001-03-01
影响因子：
4.4
通讯作者：
Miller, RA
中科院分区：
文献类型：
--
作者：
Garcia, GG;Miller, RA
共焦荧光显微镜是用来研究膜相关蛋白的再分配在幼稚T细胞从年轻和年老小鼠的转基因股票T细胞表达细胞特定的肽来源于鸽子细胞色素C,大约50%的年轻小鼠的T细胞形成配合,vith peptide-pulsed APC形成复合物,被发现在网站绑定的APC,包含CD3ε,链接器激活的T细胞(LAT),c-Cbl, p95(vav), Grb-2, PLC γ, Fyn。Lck在界面区域的分布更为均匀。双色染色显示，那些能够重新定位c-Cbl、LAT、CD3 epsilon或PLC γ的细胞通常重新定位了激活复合物的所有这四种成分。约75%重排LAT、c-Cbl或PLC γ的偶联物也表现出细胞质NF-AT向T细胞核的迁移。衰老有两个影响，首先，它导致T细胞/APC偶联物的比例减少了大约2倍，而T细胞/APC偶联物可以将9种测试蛋白质中的任何一种重新定位到免疫突触。其次，衰老减少了细胞质NF-AT在细胞间迁移的频率，这些细胞可以产生含有LAT、c-Cbl或PLC γ的免疫突触，因此，老年小鼠的初始CD4 T细胞在肽/MHC复合物诱导的激活的早期阶段至少表现出两种可分离的缺陷。
Confocal fluorescent microscopy was used to study redistribution of membrane-associated proteins in naive T cells from young and old mice from a transgenic stock whose T cells express a TCR specific for a peptide derived from pigeon cytochrome C, About 50% of the T cells from young mice that formed conjugates,vith peptide-pulsed APC were found to form complexes, at the site of binding to the APC, containing CD3 epsilon, linker for activation of T cells (LAT), and Zap-70 in a central area and c-Cbl, p95(vav), Grb-2, PLC gamma, Fyn. and Lck distributed more uniformly across the interface area. Two-color staining show ed that those cells that were able to relocalize c-Cbl, LAT, CD3 epsilon, or PLC gamma typically relocalized all four of these components of the activation complex. About 75% of conjugates that rearranged LAT, c-Cbl, or PLC gamma also exhibited cytoplasmic NF-AT migration to the T cell nucleus. Aging had two effects, First, it led to a diminution of similar to2-fold in the proportion of T cell/APC conjugates that could relocalize any of the nine tested proteins to the immune synapse. Second, aging diminished by similar to2-fold the frequency of cytoplasmic NF-AT migration among cells that could generate immune synapses containing LAT, c-Cbl, or PLC gamma, Thus naive CD4 T cells from old mice exhibit at least two separable defects in the earliest stages of activation induced by peptide/MHC complexes.