CD66 monoclonal antibodies recognize a phosphotyrosine-containing protein bearing a carcinoembryonic antigen cross-reacting antigen on the surface of human neutrophils.
CD66 monoclonal antibodies recognize a phosphotyrosine-containing protein bearing a carcinoembryonic antigen cross-reacting antigen on the surface of human neutrophils.
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DOI：
10.4049/jimmunol.148.3.852
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发表时间：
1992-02
影响因子：
4.4
通讯作者：
K. Skubitz;T. Ducker;S. Goueli
中科院分区：
文献类型：
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作者：
K. Skubitz;T. Ducker;S. Goueli
CD 66 Ag是嗜中性粒细胞特异性的“活化Ag”，因为它在静息细胞上以低密度检测，但其表面表达通过刺激（用趋化肽FMLP、钙离子载体A23187和12-O-十四烷酰基-佛波醇-13-乙酸酯）上调。磷酸化是调节蛋白质功能的重要机制。虽然大多数蛋白磷酸化的研究都集中在细胞内反应，最近的研究提供了证据的存在外蛋白激酶活性的几种类型的细胞，包括人类中性粒细胞的表面。胞外蛋白激酶活性在细胞功能中的作用是未知的，并且对该酶系统的内源性底物知之甚少。外蛋白激酶活性的生理底物的鉴定和表征应有助于理解这种酶活性在细胞功能中的作用。免疫沉淀和随后的凝胶电泳从中性粒细胞标记的蛋白与[γ-32 P]ATP显示，CD 66单抗特异性识别约180 kDa的磷蛋白的表面上的人中性粒细胞。该蛋白是人中性粒细胞外蛋白激酶活性的主要内源性底物之一。180 kDa蛋白的磷酸氨基酸分析显示，它主要含有磷酸酪氨酸。清除前的研究表明，该蛋白也被CD 15单克隆抗体和多克隆抗癌胚抗原抗血清所识别。此外，CD 66 mAb与纯化的癌胚抗原、胆汁糖蛋白和“非特异性交叉反应抗原”反应。因此，CD 66单克隆抗体识别的中性粒细胞蛋白似乎是人中性粒细胞上典型的“非特异性交叉反应抗原”的约180 kDa形式。
The CD66 Ag is a neutrophil-specific "activation Ag" in that it is detected in low density on resting cells but its surface expression is up-regulated by stimulation (with the chemotactic peptide FMLP, the calcium ionophore A23187, and 12-O-tetradeconoyl-phorbol-13-acetate). Phosphorylation is an important mechanism of regulation of protein function. Although most studies of protein phosphorylation have focused on intracellular reactions, recent studies have provided evidence for the existence of ectoprotein kinase activity on the surface of several types of cells including human neutrophils. The role of ectoprotein kinase activity in cell function is unknown and little is known about the endogenous substrates of this enzyme system. The identification and characterization of physiologic substrates of ectoprotein kinase activity should aid the understanding of the role of this enzyme activity in cell function. Immunoprecipitation and subsequent gel electrophoresis of proteins from neutrophils labeled with [gamma-32P]ATP revealed that CD66 mAb specifically recognize a approximately 180-kDa phosphoprotein on the surface of human neutrophils. This protein was one of the major endogenous substrates for human neutrophil ectoprotein kinase activity. Phosphoamino acid analysis of the 180-kDa protein revealed that it contained predominantly phosphotyrosine. Preclearing studies demonstrated that this protein was also recognized by CD15 mAb, and by polyclonal anticarcinoembryonic Ag antiserum. In addition, the CD66 mAb reacted with purified carcinoembryonic Ag, biliary glycoprotein, and "nonspecific cross-reacting Ag." Thus, the neutrophil protein recognized by CD66 mAb appears to be a approximately 180-kDa form of the classical "nonspecific cross-reacting Ag" on human neutrophils.