Rother J, Richter C, Turco L, Knoch F, Mey I, Luther S, Janshoff A, Bodenschatz E, Tarantola M
Institute of Physical Chemistry, University of Goettingen, Tammannstrasse 6, Goettingen 37077, Germany.
Research Group Biomedical Physics, Max Planck Institute for Dynamics and Self-Organization (MPIDS), Am Fassberg 17, Goettingen 37077, Germany Heart Research Center Goettingen, Robert-Koch-Strasse 40, Goettingen 37099, Germany.
Open Biol. 2015 Jun;5(6):150038. doi: 10.1098/rsob.150038.
Electromechanical function of cardiac muscle depends critically on the crosstalk of myocytes with non-myocytes. Upon cardiac fibrosis, fibroblasts translocate into infarcted necrotic tissue and alter their communication capabilities. In the present in vitro study, we determined a multiple parameter space relevant for fibrotic cardiac tissue development comprising the following essential processes: (i) adhesion to substrates with varying elasticity, (ii) dynamics of contractile function, and (iii) electromechanical connectivity. By combining electric cell-substrate impedance sensing (ECIS) with conventional optical microscopy, we could measure the impact of fibroblast-cardiomyocyte ratio on the aforementioned parameters in a non-invasive fashion. Adhesion to electrodes was quantified via spreading rates derived from impedance changes, period analysis allowed us to measure contraction dynamics and modulations of the barrier resistance served as a measure of connectivity. In summary, we claim that: (i) a preferred window for substrate elasticity around 7 kPa for low fibroblast content exists, which is shifted to stiffer substrates with increasing fibroblast fractions. (ii) Beat frequency decreases nonlinearly with increasing fraction of fibroblasts, while (iii) the intercellular resistance increases with a maximal functional connectivity at 75% fibroblasts. For the first time, cardiac cell-cell junction density-dependent connectivity in co-cultures of cardiomyocytes and fibroblasts was quantified using ECIS.
心肌的机电功能严重依赖于心肌细胞与非心肌细胞之间的相互作用。心脏纤维化时，成纤维细胞会迁移到梗死坏死组织中并改变其通讯能力。在本体外研究中，我们确定了一个与纤维化心脏组织发育相关的多参数空间，包括以下基本过程：（i）与不同弹性底物的粘附，（ii）收缩功能的动力学，以及（iii）机电连接性。通过将细胞-底物阻抗传感（ECIS）与传统光学显微镜相结合，我们能够以非侵入性方式测量成纤维细胞与心肌细胞比例对上述参数的影响。通过从阻抗变化得出的铺展率对电极粘附进行量化，周期分析使我们能够测量收缩动力学，而屏障电阻的调制则作为连接性的指标。总之，我们认为：（i）对于低成纤维细胞含量，存在一个约7 kPa的底物弹性最佳窗口，随着成纤维细胞比例增加，该窗口会向更硬的底物偏移。（ii）搏动频率随着成纤维细胞比例增加而非线性降低，而（iii）细胞间电阻随着成纤维细胞比例达到75%时功能连接性最大而增加。首次使用ECIS对心肌细胞和成纤维细胞共培养物中依赖于心脏细胞-细胞连接密度的连接性进行了量化。
