Nonuniform Internal Structure of Fibrin Fibers: Protein Density and Bond Density Strongly Decrease with Increasing Diameter
Nonuniform Internal Structure of Fibrin Fibers: Protein Density and Bond Density Strongly Decrease with Increasing Diameter
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DOI：
10.1155/2017/6385628
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发表时间：
2017-01-01
影响因子：
--
通讯作者：
Guthold, Martin
中科院分区：
文献类型：
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作者：
Li, Wei;Sigley, Justin;Guthold, Martin
血凝块的主要结构成分是纤维蛋白纤维网。长期以来，人们一直认为纤维蛋白纤维的内部结构是均匀的;也就是说，蛋白质密度和原纤维之间的键密度是均匀的，并且不依赖于纤维直径。我们进行了实验来研究纤维蛋白纤维的内部结构。我们用荧光标记的纤维蛋白原形成纤维蛋白纤维，并确定纤维的光强度I作为纤维直径D的函数。纤维蛋白分子的强度以及横截面中的纤维蛋白分子的总数按比例缩放为。D-1.4这意味着蛋白质密度（纤维蛋白/横截面积）rho（rho）不是均匀的，而是随着纤维直径D-0.6而强烈降低。较细的纤维比较粗的纤维密度大。我们还确定了杨氏模量Y作为纤维直径的函数，Y随着D的增加而强烈下降; Y按D-1.5缩放。这意味着键密度rho（B）也与D-1.5成比例。较细的纤维比较粗的纤维硬。我们的数据表明，纤维蛋白纤维有一个密集的，连接良好的核心和稀疏，松散连接的外围。相比之下，用作对照的电纺纤维蛋白原纤维具有均匀的横截面。
The major structural component of a blood clot is a meshwork of fibrin fibers. It has long been thought that the internal structure of fibrin fibers is homogeneous; that is, the protein density and the bond density between protofibrils are uniform and do not depend on fiber diameter. We performed experiments to investigate the internal structure of fibrin fibers. We formed fibrin fibers with fluorescently labeled fibrinogen and determined the light intensity of a fiber,I, as a function of fiber diameter,D. The intensity and, thus, the total number of fibrin molecules in a cross-section scaled as.. D-1.4. This means that the protein density ( fibrin per cross-sectional area),rho(rho), is not homogeneous but instead strongly decreases with fiber diameter as D-0.6. Thinner fibers are denser than thicker fibers. We also determined Young's modulus, Y, as a function of fiber diameter.Y decreased strongly with increasing D; Y scaled as D-1.5. This implies that the bond density, rho(b), also scales as D-1.5. Thinner fibers are stiffer than thicker fibers. Our data suggest that fibrin fibers have a dense, well-connected core and a sparse, loosely connected periphery. In contrast, electrospun fibrinogen fibers, used as a control, have a homogeneous cross-section.