Effect of the GPI anchor of human Thy-1 on antibody recognition and function.
Effect of the GPI anchor of human Thy-1 on antibody recognition and function.
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DOI：
10.1038/labinvest.2012.178
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发表时间：
2013-03
期刊：
影响因子：
--
通讯作者：
Hagood JS
中科院分区：
文献类型：
--
作者：
Bradley JE;Chan JM;Hagood JS
胸腺细胞分化抗原 1 (Thy-1) 是一种糖基磷脂酰肌醇 (GPI) 连接的细胞表面糖蛋白，在多种细胞类型中表达，可调节影响细胞粘附、迁移、分化和存活的信号。此外，在血清、脑脊液、静脉溃疡伤口液、类风湿性关节炎关节滑液以及最近的尿液中也检测到了 Thy-1。我们之前在细胞因子刺激的肺成纤维细胞的条件培养基中检测到 Thy-1，表明 Thy-1 脱落可能是对细胞应激的反应。体内来源的可溶性和膜结合形式的 Thy-1 在去糖基化时大小相同，这表明可溶性 Thy-1 通过 GPI 部分内的水解与其 GPI 锚的二酰基甘油部分分离。对于 Thy-1 和其他 GPI 锚定蛋白，脱脂会引起构象的稳定变化，这表现为抗体对可溶形式的亲和力发生变化。使用表位标记的重组可溶性 Thy-1，我们报告广泛使用的人 Thy-1 单克隆抗体无法通过免疫印迹检测可溶性 Thy-1。我们重新评估了之前报道的正常人肺成纤维细胞条件培养基中的 Thy-1，发现它完全不溶。这些发现表明，体液中报道的大多数 Thy-1 保留了其 GPI 锚，并且可能与膜碎片或囊泡相关。在生成 Thy-1 生物测定的抗体和对照时应考虑这种现象。此外，脱脂过程中 Thy-1 构象的变化除了影响抗体亲和力外，还可能影响可溶性与释放的膜相关形式的配体亲和力和生物功能。
Thymocyte differentiation antigen 1 (Thy-1) is a glycosylphosphatidyl inositol (GPI)-linked cell surface glycoprotein expressed on numerous cell types, which regulates signals affecting cell adhesion, migration, differentiation, and survival. In addition, Thy-1 has been detected in serum, cerebral spinal fluid, wound fluid from venous ulcers, synovial fluid from joints in rheumatoid arthritis and more recently urine. We previously detected Thy-1 in the conditioned media of cytokine-stimulated lung fibroblasts, suggesting that Thy-1 shedding may be a response to cellular stress. Soluble and membrane bound forms of Thy-1 from in vivo sources have been shown to be identical in size when deglycosylated, suggesting that soluble Thy-1 is separated from the diacyl glycerol portion of its GPI-anchor by hydrolysis within the GPI moiety. For Thy-1 and other GPI-anchored proteins, delipidation induces a stable change in conformation that manifests itself in a change in antibody affinity for soluble forms. Using epitope tagged recombinant soluble Thy-1, we report that widely available monoclonal antibodies to human Thy-1 are unable to detect soluble Thy-1 by immunoblotting. We reevaluated the Thy-1 that we previously reported in the conditioned media of normal human lung fibroblasts and found it to be entirely insoluble. These findings suggest that most Thy-1 reported in body fluids retains its GPI anchor and may be associated with membrane fragments or vesicles. This phenomenon should be considered in the generation of antibodies and controls for Thy-1 bioassays. Furthermore, the changes in Thy-1 conformation with delipidation, beyond affecting antibody affinity, likely affect the ligand affinity and biological function of soluble vs. released membrane-associated forms.
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影响因子：
2.7
作者：
Kondoh, Gen;Watanabe, Hitomi;Kinoshita, Taroh
通讯作者：
Kinoshita, Taroh
DOI：
10.1038/nbt1088-1204
发表时间：
1988-10-01
期刊：
BIO-TECHNOLOGY
影响因子：
--
作者：
HOPP, TP;PRICKETT, KS;CONLON, PJ
通讯作者：
CONLON, PJ
影响因子：
15.3
作者：
REIF, A E;ALLEN, J M
通讯作者：
ALLEN, J M
DOI：
10.1002/biof.41
发表时间：
2009-05
期刊：
BioFactors (Oxford, England)
影响因子：
--
作者：
Bradley JE;Ramirez G;Hagood JS
通讯作者：
Hagood JS
DOI：
10.1073/pnas.85.4.980
发表时间：
1988-02-01
影响因子：
11.1
作者：
LOW, MG;PRASAD, ARS
通讯作者：
PRASAD, ARS