Department of Chemistry, Physics, and Mathematics, Federal University of São Carlos, Sorocaba, 18052-780, Brazil.
Rheabiotech Laboratory Research and Development, Campinas, 13084-791, Brazil.
J Nanosci Nanotechnol. 2019 Dec 1;19(12):7564-7573. doi: 10.1166/jnn.2019.16734.
In this work, we considered the autoantibodies proposed as putative biomarkers of demyelination taking into account their reactivity towards myelin oligodendrocyte glycoprotein (MOG) and myelin basic protein (MBP). These myelin proteins are among the most commonly researched targets in the immunopathology of demyelinating diseases. In this context, the development of assays for autoantibody detection can contribute as a predictive value for the early diagnosis of demyelinating diseases. Hence, we aimed to address the application of silver nanoparticles (AgNPs) as a sensing device of autoantibodies. AgNPs were synthesized via a chemical reduction method and characterized using atomic force microscopy (AFM), X-ray diffractometry, dynamic light scattering, and UV-visible spectrophotometry. The process of peptide conjugation on the nanoparticles was also analyzed. The autoantibody recognition by the peptide-conjugated AgNPs was evaluated with UV-visible spectrophotometry, atomic force spectroscopy (AFS), and color changing. AgNPs exhibited spherical morphology, low polydispersity, face-centered cubic crystal structure, and an average size of 29.3±3.0 nm. The hydrodynamic diameter variation and AFM showed that the MBP peptide induced greater agglomeration, compared to MOG peptide. The AFS measurements indicated the efficient binding of peptides to the AgNPs maintaining their activity, revealed by typical adhesion force and shapes of curves. The absorption spectrum features were more affected by the interaction with the specific autoantibodies, which also caused a visible color change in suspension providing a qualitative response. We described a preliminary study of MOG- and MBP-conjugated AgNPs which showed to be applicable in the autoantibody recognition. These have promising implication in the searching for biological markers for diagnostic purposes in the demyelination context, in which the nanoscale sensing exploitation is recent.
在这项工作中，我们考虑了被认为是脱髓鞘潜在生物标志物的自身抗体，同时考虑了它们对髓鞘少突胶质细胞糖蛋白（MOG）和髓鞘碱性蛋白（MBP）的反应性。这些髓鞘蛋白是脱髓鞘疾病免疫病理学中最常研究的靶点之一。在这种情况下，开发自身抗体检测的检测方法可以作为脱髓鞘疾病早期诊断的预测值。因此，我们旨在研究银纳米颗粒（AgNPs）作为自身抗体检测的传感装置。AgNPs 通过化学还原法合成，并通过原子力显微镜（AFM）、X 射线衍射、动态光散射和紫外可见分光光度法进行了表征。还分析了纳米颗粒上肽结合的过程。通过紫外可见分光光度法、原子力光谱（AFS）和颜色变化评估了肽偶联的 AgNPs 对自身抗体的识别。AgNPs 呈球形形态，具有低多分散性、面心立方晶体结构和平均尺寸为 29.3±3.0nm。水动力直径变化和 AFM 表明，与 MOG 肽相比，MBP 肽诱导了更大的聚集。AFS 测量表明，肽与 AgNPs 的有效结合保持了它们的活性，这通过典型的粘附力和曲线形状得到证实。吸收光谱特征受与特定自身抗体相互作用的影响更大，这也导致悬浮液中发生可见的颜色变化，提供定性反应。我们描述了 MOG 和 MBP 偶联 AgNPs 的初步研究，结果表明它们可用于自身抗体的识别。这些在寻找脱髓鞘背景下的诊断生物标志物方面具有广阔的应用前景，纳米级传感技术的应用在该领域尚属新兴。
