Magnetic Resonance Imaging of Contracting Ultrathin Cardiac Tissue.
Magnetic Resonance Imaging of Contracting Ultrathin Cardiac Tissue.
复制标题
收缩超薄心肌组织的磁共振成像。
DOI：
10.1088/2057-1976/ab1c1c
复制
发表时间：
2019
影响因子：
1.4
通讯作者：
London,Barry
中科院分区：
文献类型：
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作者：
Shusterman,Vladimir;Nagpal,Prashant;Thedens,Daniel;Zhu,Xiaodong;Matasic,DanielS;Yoon,Jin-Young;Morgan,Gina;Hoffman,Stacy;London,Barry
目的将心脏组织贴片整合到跳动的心脏中，并评估这种整合对心脏收缩力的长期影响是再生医学新兴领域面临的两个挑战。本初步研究提供了用于体外收缩多细胞心脏组织结构（mtc）成像的工具，并证明了使用CINE MRI跟踪超薄股和心脏组织层的股几何形状和收缩的早期发展的可行性。将培养的超薄（~ 50 - 100微米）大鼠新生心肌细胞MTCs镀于矩形细胞室（4.5× 2.0 cm）中，在细胞室底部嵌入超薄碳EP电极或不嵌入超薄碳EP电极。在细胞发育的第5-9天进行二维，稳态自由进动（SSFP） CINE MRI，细胞显微镜和组织摄影。使用非收缩心脏组织和充满细胞培养基的无细胞腔来评估潜在的混杂因素和MRI伪影。主要结果：第7天形成同步宫缩；个体收缩组织链在第9天变得可识别。SSFP图像中的整体模式和细部结构以及运动模式与显微镜和摄影图像非常吻合。在非收缩MTCs或无细胞培养基中，显微镜或CINE MRI均未发现同步运动。EP记录显示清晰的去极化和复极化波形；碳电极产生的成像伪影很小。这项初步研究证明了在常用的临床扫描仪上成像超薄二维心脏组织的心脏链模式和收缩活动的可行性。
ObjectiveIntegrating cardiac-tissue patches into the beating heart and evaluating the long-term effects of such integration on cardiac contractility are two challenges in an emerging field of regenerative medicine. This pilot study presents tools for the imaging of contracting multicellular cardiac tissue constructs (MTCs) in vitro and demonstrates the feasibility of tracking the early development of strand geometry and contractions in ultrathin strands and layers of cardiac tissue using CINE MRI.ApproachCultured, ultrathin (∼ 50–100-micron) MTCs of rat neonatal cardiomyocytes were plated in rectangular cell chambers (4.5× 2.0 cm) with and without ultrathin, carbon EP electrodes embedded in the floor of the cell chamber. Two-dimensional, steady-state free precession (SSFP) CINE MRI, cell microscopy, and tissue photography were performed on Days 5–9 of cell development. Potential confounders and MRI artifacts were evaluated using non-contracting cardiac tissues and cell-free chambers filled with the cell-culture medium.Main resultsSynchronized contractions formed by Day 7; individual contracting tissue strands became identifiable by Day 9. The global patterns and details of the strand geometry and movement patterns in the SSFP images were in excellent agreement with microscopic and photographic images. No synchronized movement was identifiable by either microscopy or CINE MRI in the non-contracting MTCs or the cell-free medium. The EP recordings revealed well-defined depolarization and repolarization waveforms; the imaging artifacts generated by the carbon electrodes were small.SignificanceThis pilot study demonstrates the feasibility of imaging cardiac-strand patterns and contractile activity in ultrathin, two-dimensional cardiac tissue in commonly used clinical scanners.