AbstractProgrammed death-ligand 1 (PD-L1) is overexpressed in a variety of cancer cells. Using protein SELEX, aptamers against PD-L1 were identified. After 10 rounds of selection, 2 aptamers (Apt5 and Apt33) were chosen. Due to the higher specificity and affinity of Apt5 for PD-L1, this aptamer was characterized in detail. The ATTO 647 N–labeled aptamer readily internalizes into PD-L1 positive A2780 cells where it can detect human ovarian carcinoma. Hence, fluorometry provides a rapid and sensitive quantitative tool for the detection of these cancer cells with limit of detection (LOD) as low as 10 cells.mL−1 and linear response in the range between 50 and 1000 cells.mL−1. In our perception, the Apt 5 aptamer holds great promise for use in cancer diagnosis and therapy. Graphical abstractUsing Protein-SELEX method a new DNA aptamer (APT5) was selected which bound specifically and with high affinity to PD-L1 protein. The ATTO 647 N–labeled aptamer was internalized into PD-L1 positive cells (A2780) but it did not detect HEK 239 cells (PD-L1 negative).

中文翻译：

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一种识别跨膜蛋白PDL-1（程序性死亡配体1）的适配体及其在人卵巢癌细胞荧光单细胞检测中的应用

摘要程序性死亡配体 1 (PD-L1) 在多种癌细胞中过度表达。使用蛋白质 SELEX，鉴定了针对 PD-L1 的适体。经过 10 轮选择后，选择了 2 个适体（Apt5 和 Apt33）。由于 Apt5 对 PD-L1 具有更高的特异性和亲和力，因此对该适体进行了详细表征。ATTO 647 N 标记的适体很容易内化到 PD-L1 阳性 A2780 细胞中，在那里它可以检测人卵巢癌。因此，荧光法为检测这些癌细胞提供了一种快速而灵敏的定量工具，其检测限 (LOD) 低至 10 个细胞.mL-1，线性响应范围在 50 和 1000 个细胞.mL-1 之间。在我们看来，Apt 5 适配体在癌症诊断和治疗中具有广阔的应用前景。图形摘要使用蛋白质-SELEX 方法选择了一种新的 DNA 适体 (APT5)，它与 ​​PD-L1 蛋白特异性结合并具有高亲和力。ATTO 647 N 标记适体被内化到 PD-L1 阳性细胞 (A2780) 中，但未检测到 HEK 239 细胞（PD-L1 阴性）。