Department of Medical Biotechnologies and Translational Medicine, Università degli Studi di Milano, L.I.T.A., Via F.lli Cervi 93, 20090 Segrate, Italy.
Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, 85748 Garching, Germany.
Int J Mol Sci. 2019 Jul 29;20(15):3712. doi: 10.3390/ijms20153712.
The fate of macromolecules of biological or pharmacological interest that enter the mucus barrier is a current field of investigation. Studies of the interaction between the main constituent of mucus, mucins, and molecules involved in topical transmucoidal drug or gene delivery is a prerequisite for nanomedicine design. We studied the interaction of mucin with the bio-inspired arginine-derived amphoteric polymer d,l-ARGO7 by applying complementary techniques. Small angle X-ray scattering in bulk unveiled the formation of hundreds of nanometer-sized clusters, phase separated from the mucin mesh. Quartz microbalance with dissipation and neutron reflectometry measurements on thin mucin layers deposited on silica supports highlighted the occurrence of polymer interaction with mucin on the molecular scale. Rinsing procedures on both experimental set ups showed that interaction induces alteration of the deposited hydrogel. We succeeded in building up a new significant model for epithelial tissues covered by mucus, obtaining the deposition of a mucin layer 20 Å thick on the top of a glycolipid enriched phospholipid single membrane, suitable to be investigated by neutron reflectometry. The model is applicable to unveil the cross structural details of mucus-covered epithelia in interaction with macromolecules within the Å discreteness.
进入黏液屏障的具有生物或药理学意义的大分子的命运是当前研究的一个领域。研究黏液主要成分粘蛋白与局部跨黏膜药物或基因传递中涉及的分子之间的相互作用是纳米医学设计的前提。我们通过应用互补技术研究了粘蛋白与生物启发的精氨酸衍生两性聚合物 d,l-ARGO7 的相互作用。在体中的小角度 X 射线散射揭示了数百纳米大小的簇的形成，这些簇与粘蛋白网格分离。在涂有二氧化硅衬底的薄粘蛋白层上进行的石英微量天平耗散测量和中子反射测量突出了聚合物与粘蛋白在分子水平上相互作用的发生。在两个实验装置上的冲洗程序表明，相互作用诱导了沉积水凝胶的改变。我们成功地建立了一个新的黏液覆盖的上皮组织的重要模型，在富含糖脂的磷脂单层膜的顶部获得了 20 Å 厚的粘蛋白层的沉积，适合用中子反射测量法进行研究。该模型适用于揭示具有 Å 离散性的与大分子相互作用的黏液覆盖上皮的交叉结构细节。
