Abstract：
Nucleic-acid aptamers are of strong interest for diagnosis and therapy. Compared with antibodies, they are smaller, stable upon variations in temperature, easy to modify, and have higher tissue-penetration abilities. However, they have been little described as detection probes in histology studies of human tissue sections. In this study, we performed fluorescence imaging with two aptamers targeting cell-surface receptors EGFR and integrin α5β1, both involved in the aggressiveness of glioblastoma. The aptamers\' cell-binding specificities were confirmed using confocal imaging. The affinities of aptamers for glioblastoma cells expressing these receptors were in the 100-300 nM range. The two aptamers were then used to detect EGFR and integrin α5β1 in human glioblastoma tissues and compared with antibody labeling. Our aptafluorescence assays proved to be able to very easily reveal, in a one-step process, not only inter-tumoral glioblastoma heterogeneity (differences observed at the population level) but also intra-tumoral heterogeneity (differences among cells within individual tumors) when aptamers with different specificities were used simultaneously in multiplexing labeling experiments. The discussion also addresses the strengths and limitations of nucleic-acid aptamers for biomarker detection in histology.
摘要：
核酸适体对于诊断和治疗具有强烈的兴趣。与抗体相比，它们更小，在温度变化时稳定，易于修改，并具有较高的组织穿透能力。然而,在人体组织切片的组织学研究中，它们很少被描述为检测探针。在这项研究中,我们使用靶向细胞表面受体EGFR和整合素α5β1的两种适体进行荧光成像,这两种适体均参与胶质母细胞瘤的侵袭性.使用共聚焦成像确认适体的细胞结合特异性。适体对表达这些受体的成胶质细胞瘤细胞的亲和力在100-300nM范围内。然后将这两种适体用于检测人胶质母细胞瘤组织中的EGFR和整联蛋白α5β1，并与抗体标记进行比较。我们的aptaflurosuments被证明能够很容易地揭示，在一步的过程中，当在多重标记实验中同时使用具有不同特异性的适体时,不仅肿瘤胶质母细胞瘤间异质性(在群体水平观察到的差异),而且肿瘤内异质性(单个肿瘤内细胞间的差异).讨论还解决了用于组织学中的生物标志物检测的核酸适体的强度和局限性。
