Contraction pressure analysis using optical imaging in normal and MYBPC3-mutated hiPSC-derived cardiomyocytes grown on matrices with tunable stiffness

Current in vivo disease models and analysis methods for cardiac drug development have been insufficient in providing accurate and reliable predictions of drug efficacy and safety. Here, we propose a custom optical flow-based analysis method to quantitatively measure recordings of contracting cardiomyocytes on polydimethylsiloxane (PDMS), compatible with medium-throughput systems. Movement of the PDMS was examined by covalently bound fluorescent beads on the PDMS surface, differences caused by increased substrate stiffness were compared, and cells were stimulated with β-agonist. We further validated the system using cardiomyocytes treated with endothelin-1 and compared their contractions against control and cells incubated with receptor antagonist bosentan. After validation we examined two MYBPC3-mutant patient-derived cell lines. Recordings showed that higher substrate stiffness resulted in higher contractile pressure, while beating frequency remained similar to control. β-agonist stimulation resulted in both higher beating frequency as well as higher pressure values during contraction and relaxation. Cells treated with endothelin-1 showed an increased beating frequency, but a lower contraction pressure. Cells treated with both endothelin-1 and bosentan remained at control level of beating frequency and pressure. Lastly, both MYBPC3-mutant lines showed a higher beating frequency and lower contraction pressure. Our validated method is capable of automatically quantifying contraction of hiPSC-derived cardiomyocytes on a PDMS substrate of known shear modulus, returning an absolute value. Our method could have major benefits in a medium-throughput setting.</p

Characterisation of iPSC-cardiomyocyte contractions using optical imaging

Congestive heart failure is a common illness affecting 1-2% of the population in developed countries. Due to the recent attempts to replace animal models, as well as the poor predictive value of animal models in heart failure. The development of a new in vivo heart model is critical for the development and testing of new drugs. The HeartCHIP project aims to develop such a model. As part of the development process different analyses need to be developed for characterisation of heart muscle cells. For this purpose, more traditional methods such measuring the action potential can be used. But newer methods such as measuring the contraction by means of optical imaging are being developed and tested. In this paper, image analysis characterisation of cardiomyocytes and vascular smooth muscle cells are explored. Using images recorded from transmission light as well as fluorescent beads the movements of a monolayer of cells is tracked and analysed. Next to this, the potential for live cell imaging of actin structures during contraction is explored, allowing the study of sarcomere compaction during contraction.Applied Sciences | Nanobiolog

The state of Baumol’s disease for the OECD countries

Management of Technology (MoT