Electrochemically Guided Collagen Synthesis for Functional Tissue Engineering

用于功能组织工程的电化学引导胶原蛋白合成

• 批准号: 7691366
• 负责人: Ozan Akkus
• 金额: $ 14.66万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-26 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7691366
• 关键词: Affect; Amendment; Behavior; Binding; Biocompatible Materials; Biological Assay; Biological Factors; Biomechanics; Biomimetics; Blood Vessels; Body Fluids; Bone Marrow; Caliber; Cells; Collagen; Collagen Fibril; Collagen Type I; Connective Tissue; Cues; Data; Dermatan Sulfate; Development; Dimensions; Fiber; Fibronectins; Fostering; Gel; Genotype; Glutaral; Goals; Hand; In Vitro; Length; Ligaments; Measures; Mechanics; Mesenchymal Stem Cells; Methods; Molecular; Morphology; Nature; Pathway interactions; Pattern; Peptides; Phase; Phenotype; Phosphate Buffer; Play; Process; Property; Rattus; Role; Saline; Shapes; Simulate; Site; Skin; Solutions; Stem cells; Tenascin; Tendon structure; Testing; Tissue Engineering; Tissues; Tubular formation; Weight-Bearing state; adult stem cell; analog; base; biomaterial compatibility; bone; clinically significant; crosslink; decorin; density; electric field; genipin; improved; novel; pH gradient; physical property; progenitor; prospective; public health relevance; regenerative; repaired; research study; scaffold; stem cell differentiation; synthetic construct; three dimensional structure

DESCRIPTION (provided by applicant): Collagen plays a central role as a biomaterial and as a scaffold in the regenerative tissue replacement strategies. Existing synthetic analogs of collagen have extremely poor biomechanical properties in comparison to the tissues they are targeted to replace due, in part, to the lack of orientation in hierarchical orders above the level of fibers. The overall goal of the proposed study is to demonstrate the feasibility of a novel biomechanically competent collagenous tissue engineering scaffold fabricated by: 1) an unconventional electrochemical process to attain an unprecedented level of molecular alignment and molecular packing density persistent across multiple levels of structural hierarchies, and, 2) the control of interfibrillar attachment by use of a biomimetic decorin-like linkage molecule. Phase 1 of proposed studies will elucidate the mechanisms by which collagen solutions achieve long-range order under the effect of weak currents applied to directly to the solutions. The effects of pH gradient electric current amplitude and collagen concentration on the hierarchical organization of collagen will be investigated to optimize the synthetic process. The strength of resulting oriented collagen gels will be improved by identifying the appropriate type and concentration of crosslinking amongst genipin and glutaraldehyde. {The D-banding pattern and collagen fibril diameter will be improved by modulating the phosphate buffered saline treatment conditions.} The viscoelastic properties of oriented constructs will be modified by decorin mimics consisting of dermatan sulfate attached to peptide motifs which selectively bind to type I collagen molecules. Mechanical properties of resulting synthetic constructs will be assessed by macroscale mechanical tests and compared to those of rat tendon, a reference natural tissue. {Phase 2 is going to assess the differentiation of bone marrow derived mesenchymal stem cell progenitors on this material towards tenocytic lineage and foster this differentiation pathway by the mechanical cue.} Overall, the proposed study will: a) optimize the fabrication process variables of a novel fabrication method to obtain highly oriented tendon-mimicking constructs, and, b) assess the feasibility of the material as a tissue engineering scaffold by investigating phenotypic and genotypic behavior of bone marrow derived stem-cell progenitors seeded within the three-dimensional structures consisting of multiple collagenous bundles. A biomaterial of this nature may play a key role in creating strategies towards replacement of load bearing connective tissues such as tendons, ligaments, bones and vascular walls provided that the current study proves its feasibility. PUBLIC HEALTH RELEVANCE: The overall goal of the proposed study is to demonstrate the feasibility of a novel collagenous tissue engineering scaffold with mechanical properties converging those of tendon or ligaments. The study will assess the promise of this novel material by investigating whether adult stem cells seeded on this material differentiate to act like tendon cells.

描述（由申请人提供）：胶原蛋白作为生物材料和再生组织替代策略中的支架发挥着核心作用。现有的胶原蛋白的合成类似物与它们靶向替换的组织相比具有极差的生物力学性质，部分原因是缺乏在纤维水平以上的分级顺序中的取向。提出的研究的总体目标是证明一种新的生物力学能力的胶原组织工程支架的可行性，该支架通过以下方式制造：1）非常规电化学过程，以获得前所未有的分子排列水平和在多个结构层次上持续的分子堆积密度，以及2）通过使用仿生核心蛋白聚糖样连接分子控制原纤维间的附着。拟议研究的第1阶段将阐明胶原蛋白溶液在直接施加于溶液的弱电流作用下实现长程有序的机制。研究了pH梯度电流幅值和胶原蛋白浓度对胶原蛋白层次结构的影响，优化了合成工艺。通过确定京尼平和戊二醛之间交联的适当类型和浓度，将提高所得定向胶原凝胶的强度。{The通过调节磷酸盐缓冲盐水处理条件将改善D-带型和胶原纤维直径。定向构建体的粘弹性将通过核心蛋白聚糖模拟物进行修饰，所述核心蛋白聚糖模拟物由连接至肽基序的硫酸皮肤素组成，所述肽基序选择性地结合至I型胶原分子。将通过宏观力学试验评估所得合成结构的力学性能，并与大鼠肌腱（一种参考天然组织）的力学性能进行比较。{第2阶段将评估骨髓源性间充质干细胞祖细胞在该材料上向腱细胞谱系的分化，并通过机械提示促进该分化途径。}总体而言，所提出的研究将：a）优化新型制造方法的制造工艺变量，以获得高度定向的肌腱模拟结构，以及，B）通过研究在由多个胶原束组成的三维结构内接种的骨髓源性干细胞祖细胞的表型和基因型行为，评估材料作为组织工程支架的可行性。这种性质的生物材料可能在制定替代承重结缔组织（如肌腱、韧带、骨骼和血管壁）的策略中发挥关键作用，前提是当前研究证明其可行性。 公共卫生相关性：提出的研究的总体目标是证明一种新的胶原组织工程支架的可行性，其机械性能与肌腱或韧带的机械性能趋同。这项研究将通过调查接种在这种材料上的成体干细胞是否分化为肌腱细胞来评估这种新型材料的前景。

项目成果

Tenogenic differentiation of human MSCs induced by the topography of electrochemically aligned collagen threads.

• DOI: 10.1016/j.biomaterials.2011.11.066
• 发表时间: 2012-03
• 期刊: BIOMATERIALS
• 影响因子: 14
• 作者: Kishore, Vipuil;Bullock, Whitney;Sun, Xuanhao;Van Dyke, William Scott;Akkus, Ozan
• 通讯作者: Akkus, Ozan

Incorporation of a decorin biomimetic enhances the mechanical properties of electrochemically aligned collagen threads.

• DOI: 10.1016/j.actbio.2011.02.035
• 发表时间: 2011-06
• 期刊: ACTA BIOMATERIALIA
• 影响因子: 9.7
• 作者: Kishore, Vipuil;Paderi, John E.;Akkus, Anna;Smith, Katie M.;Balachandran, Dave;Beaudoin, Stephen;Panitch, Alyssa;Akkus, Ozan
• 通讯作者: Akkus, Ozan

Comparison of morphology, orientation, and migration of tendon derived fibroblasts and bone marrow stromal cells on electrochemically aligned collagen constructs.

• DOI: 10.1002/jbm.a.32783
• 发表时间: 2010-09-15
• 期刊: JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A
• 影响因子: 4.9
• 作者: Gurkan, Umut Atakan;Cheng, Xingguo;Kishore, Vipuil;Uquillas, Jorge Alfredo;Akkus, Ozan
• 通讯作者: Akkus, Ozan