Sialic acid-binding immunoglobulin-like lectin 15 (Siglec 15) is a novel immunomodulatory target and was identified as an immune suppressor in the tumor microenvironment. Accurate assessment of Siglec 15 expression levels is critical for cancer prognosis and treatment. In this work, a natural receptor-based immunoelectrochemical sensor is designed to mimic the interaction between Siglec 15 and DNAX-activation protein (DAP 12) in the cellular signal pathway. DAP 12 labeled with the electrochemical signal molecule Fc is recognized by Siglec 15 through specific interaction on the electrode surface and used as the signal reporter. Anti-Siglec 15 modified MNPs (MNPs-Ab) were used as the extraction agent for the magnetic extraction of target analytes in complex matrices. Free Anti-Siglec 15 will "squeeze out" the DAP 12-Fc to bind the Siglec 15 on the electrode surface, resulting a sensitive electrochemical signal change according to the Siglec 15 concentration in sample. Natural receptor-based competitive assay ensure the efficient binding between antibody and Siglec 15 and decrease the nonspecific interaction. Therefore, this simple natural receptor-based competitive assay with sensitivity and selectivity has potential for practical clinical application.

中文翻译：

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基于自然受体的竞争性免疫电化学分析法，用于Siglec 15的超灵敏检测。

结合唾液酸的免疫球蛋白样凝集素15（Siglec 15）是一种新型的免疫调节靶标，并被确定为肿瘤微环境中的一种免疫抑制剂。准确评估Siglec 15的表达水平对于癌症的预后和治疗至关重要。在这项工作中，基于自然受体的免疫电化学传感器被设计为模拟细胞信号途径中Siglec 15与DNAX激活蛋白（DAP 12）之间的相互作用。Siglec 15通过电极表面上的特定相互作用识别标记有电化学信号分子Fc的DAP 12，并将其用作信号报告基因。Anti-Siglec 15修饰的MNP（MNPs-Ab）用作提取剂，用于磁性提取复杂基质中的目标分析物。免费的Anti-Siglec 15将“挤出” DAP 12-Fc结合到电极表面上的Siglec 15，根据样品中Siglec 15的浓度产生敏感的电化学信号变化。基于天然受体的竞争性测定可确保抗体与Siglec 15之间的有效结合，并减少非特异性相互作用。因此，这种具有敏感性和选择性的简单的基于天然受体的竞争性测定法在实际临床应用中具有潜力。