The Interaction between Adult Cardiac Fibroblasts and Embryonic Stem Cell-Derived Cardiomyocytes Leads to Proarrhythmic Changes inIn VitroCocultures

Abstract

Transplantation of stem cell-derived cardiomyocytes is one of the most promising therapeutic approaches after myocardial infarction, as loss of cardiomyocytes is virtually irreversible by endogenous repair mechanisms. In myocardial scars, transplanted cardiomyocytes will be in immediate contact with cardiac fibroblasts. While it is well documented how the electrophysiology of neonatal cardiomyocytes is modulated by cardiac fibroblasts of the same developmental stage, it is unknown how adult cardiac fibroblasts (aCFs) affect the function of embryonic stem cell-derived cardiomyocytes (ESC-CMs). To investigate the effects of aCFs on ESC-CM electrophysiology, we performed extra- and intracellular recordings of murine aCF-ESC-CM cocultures. We observed that spontaneous beating behaviour was highly irregular in aCF-ESC-CM cocultures compared to cocultures with mesenchymal stem cells (coefficient of variation of the interspike interval: 40.5 ± 15.2% versus 9.3 ± 2.0%, p = 0.008) and that action potential amplitude and maximal upstroke velocity (V max) were reduced (amplitude: 52.3 ± 1.7 mV versus 65.1 ± 1.5 mV, V max: 7.0 ± 1.0 V/s versus 36.5 ± 5.3 V/s), while action potential duration (APD) was prolonged (APD50: 25.6 ± 1.0 ms versus 16.8 ± 1.9 ms, p < 0.001; APD90: 52.2 ± 1.5 ms versus 43.3 ± 3.3 ms, p < 0.01) compared to controls. Similar changes could be induced by aCF-conditioned medium. We conclude that the presence of aCFs changes automaticity and induces potentially proarrhythmic changes of ESC-CM electrophysiology.

3D Co-culture of hiPSC-Derived Cardiomyocytes With Cardiac Fibroblasts Improves Tissue-Like Features of Cardiac Spheroids

“…Interestingly, opposite results of co-culturing in spheroids and monolayers were found as co-culture spheroids showed a faster spontaneous beating rate, but monolayer co-cultures a slower spontaneous rate. This is in agreement with earlier studies that showed diminished contractile capacity of 2D-cultured, neonatal rat cardiomyocytes exposed to CF-conditioned medium (LaFramboise et al, 2007) and with a study using murine adult cardiac fibroblasts and stem-cell derived cardiomyocytes in 2D-co-culture (Trieschmann et al, 2016). Fibroblast-conditioned medium was reported to stimulate the percentage of spontaneously beating cardiomyocytes with endothelin-1 secretion from fibroblasts being responsible for the observed effect (Suzuki et al, 1997).…”

Developmental stage-dependent effects of cardiac fibroblasts on function of stem cell-derived engineered cardiac tissues

“…On the other hand, the presence of adult (and to a lesser extent, fetal) CFs tended to increase the apparent size of CMs. More recently, adult CFs were found to deteriorate the electrophysiological function of mESC-CMs in 2D co-culture 44 .…”

Nano‐ and Microfabrication for Engineering Native‐Like Muscle Tissues

“…This was indicated by the observation of lower conduction velocity in cardiac patches that were constructed with higher ratio of FBs . Consistently, Trieschmann et al observed arrhythmic activities and prolonged action potential duration (APD) when coculturing cardiomyocytes with adult cardiac FBs compared to cocultures with MSCs. Therefore, the proportion of FBs should be decided thoughtfully when constructing muscle tissues.…”