Centre for BioNano Interactions, School of Chemistry , University College Dublin , Belfield, Dublin 4 , Ireland.
UCD Conway Institute of Biomolecular and Biomedical Research, School of Biomolecular and Biomedical Science , University College Dublin , Belfield, Dublin 4 , Ireland.
ACS Nano. 2018 May 22;12(5):4930-4937. doi: 10.1021/acsnano.8b02014. Epub 2018 Apr 26.
Key practical challenges such as understanding the immunological processes at the nanoscale and controlling the targeting and accumulation of nano-objects in vivo now further stimulate efforts to underpin phenomenological knowledge of the nanoscale with more mechanistic and molecular insight. Thus, the question as to what constitutes nanoscale biological identity continues to evolve. Certainly nanoparticles in contact with a complex biological milieu develop a biological identity, differing from the original nanomaterial, now referred to as the "biomolecular corona". However, this surface-adsorbed layer of biomolecules may in some circumstance lead to different forms of receptor-particle interactions not evident only from the identity of the surface-adsorbed biomolecules and hard to predict or detect by current physicochemical methods. Here we show that scavenger receptors may recognize complex as yet unidentified biomolecular surface layer motifs, even when no current physicochemical analysis is capable of doing so. For instance, fluorescently labeled SiO nanoparticles in a biological milieu are strongly recognized by the macrophage receptor with collagenous structure (MARCO) in even dense biological media (human serum) apparently using a form of binding with which most of the MARCO's known ligands ( e. g., LPS, modified LDL) fail to compete. Such observations may suggest the need for a much stronger emphasis on nanoscale receptor-corona and other biomolecular interaction studies if one wishes to unravel how biomolecular recognition drives outcomes in the nanoscale biological domain.
目前，一些实际问题，如理解纳米尺度的免疫学过程和控制纳米物体在体内的靶向和积累，进一步激发了人们努力用更具机制和分子洞察力来支持纳米尺度的现象学知识。因此，什么构成纳米尺度的生物学特性这一问题仍在不断发展。当然，与复杂生物环境接触的纳米颗粒会形成一种生物学特性，与原始纳米材料不同，现在被称为“生物分子冠”。然而，这种表面吸附的生物分子层在某些情况下可能导致不同形式的受体-颗粒相互作用，这些作用不仅来自表面吸附生物分子的特性，而且很难通过当前的物理化学方法来预测或检测。在这里，我们表明，即使当前的物理化学分析无法做到这一点，清道夫受体也可能识别复杂的、尚未确定的生物分子表面层基序。例如，在生物环境中用荧光标记的 SiO2 纳米颗粒在即使是密集的生物介质（人血清）中也能被具有胶原蛋白结构的巨噬细胞受体（MARCO）强烈识别，显然是通过一种与 MARCO 的大多数已知配体（如 LPS、修饰的 LDL）都无法竞争的结合形式。这些观察结果可能表明，如果希望揭示生物分子识别如何驱动纳米尺度生物学领域的结果，那么需要更加重视纳米尺度的受体-冠和其他生物分子相互作用的研究。
