PDF(Pubmed)
Abstract：
Lipoproteins (LPs) are micelle-like structures with a similar size to extracellular vesicles (EVs) and are therefore often co-isolated, as intensively discussed within the EV community. LPs from human blood plasma are of particular interest as they are responsible for the deposition of cholesterol ester and other fats in the artery, causing lesions, and eventually atherosclerosis. Plasma lipoproteins can be divided according to their size, density and composition into chylomicrons (CM), very-low-density lipoproteins (VLDL), low-density lipoproteins (LDL) and high-density lipoproteins (HDL). Here, we use atomic force microscopy for mechanical characterization of LPs. We show that the nanoindentation approach used for EV analysis can also be used to characterize LPs, revealing specific differences between some of the particles. Comparing LPs with each other, LDL exhibit a higher bending modulus as compared to CM and VLDL, which is likely related to differences in cholesterol and apolipoproteins. Furthermore, CM typically collapse on the surface after indentation and HDL exhibit a very low height after surface adhesion both being indications for the presence of LPs in an EV sample. Our analysis provides new systematic insights into the mechanical characteristics of LPs.
摘要：
脂蛋白（LPs）是胶束样结构，其大小与细胞外囊泡（EV）相似，因此通常是共同分离的，正如电动汽车社区内深入讨论的那样。来自人血浆的LP特别令人感兴趣，因为它们负责胆固醇酯和其他脂肪在动脉中的沉积，引起病变，最终是动脉粥样硬化。血浆脂蛋白可以根据它们的大小来划分,密度和组成为乳糜微粒（CM），极低密度脂蛋白（VLDL），低密度脂蛋白（LDL）和高密度脂蛋白（HDL）。这里,我们使用原子力显微镜对LP进行机械表征。我们表明，用于EV分析的纳米压痕方法也可以用来表征LP，揭示某些粒子之间的特定差异。将LP相互比较，与CM和VLDL相比，LDL表现出更高的弯曲模量，这可能与胆固醇和载脂蛋白的差异有关。此外，CM通常在压痕后在表面上塌陷,HDL在表面粘附后表现出非常低的高度,这两者都是EV样品中存在LP的指示。我们的分析为LP的机械特性提供了新的系统见解。
