Mironov Vladimir, Kasyanov Vladimir, Zheng Shu Xiao, Eisenberg Carol, Eisenberg Leonard, Gonda Steve, Trusk Thomas, Markwald Roger R, Prestwich Glenn D
Medical University of South Carolina, Charleston, SC 29426, USA.
Biomaterials. 2005 Dec;26(36):7628-35. doi: 10.1016/j.biomaterials.2005.05.061.
Achieving the optimal cell density and desired cell distribution in scaffolds is a major goal of cell seeding technologies in tissue engineering. In order to reach this goal, a novel centrifugal casting technology was developed using in situ crosslinkable hyaluronan-based (HA) synthetic extracellular matrix (sECM). Living cells were suspended in a viscous solution of thiol-modified HA and thiol-modified gelatin, a polyethyleneglycol diacrylate crosslinker was added, and a hydrogel was formed during rotation. The tubular tissue constructs consisting of a densely packed cell layer were fabricated with the rotation device operating at 2000 rpm for 10 min. The majority of cells suspended in the HA mixture before rotation were located inside the layer after centrifugal casting. Cells survived the effect of the centrifugal forces experienced under the rotational regime employed. The volume cell density (65.6%) approached the maximal possible volume density based on theoretical sphere packing models. Thus, centrifugal casting allows the fabrication of tubular constructs with the desired redistribution, composition and thickness of cell layers that makes the maximum efficient use of available cells. Centrifugal casting in this sECM would enable rapid fabrication of tissue-engineered vascular grafts, as well as other tubular and planar tissue-engineered constructs.
在支架中实现最佳细胞密度和理想的细胞分布是组织工程中细胞接种技术的主要目标。为了实现这一目标，利用可原位交联的基于透明质酸（HA）的合成细胞外基质（sECM）开发了一种新型离心铸造技术。将活细胞悬浮在硫醇修饰的HA和硫醇修饰的明胶的粘性溶液中，加入聚乙二醇二丙烯酸酯交联剂，并在旋转过程中形成水凝胶。通过旋转装置以2000 rpm运行10分钟，制备出由紧密堆积的细胞层组成的管状组织构建体。旋转前悬浮在HA混合物中的大多数细胞在离心铸造后位于该层内部。细胞在所用旋转条件下所经历的离心力作用下存活下来。基于理论球体堆积模型，体积细胞密度（65.6%）接近最大可能的体积密度。因此，离心铸造能够制造出具有所需细胞层重新分布、组成和厚度的管状构建体，从而最大限度地有效利用可用细胞。在这种sECM中进行离心铸造将能够快速制造组织工程血管移植物以及其他管状和平面组织工程构建体。
