In Vitro Assessment of Cardiac Function Using Skinned Cardiomyocytes
June 22nd, 2020
6.8K views
This protocol aims to describe step-by-step the technique of extraction and assessment of cardiac function using skinned cardiomyocytes. This methodology allows measurement and acutemodulation of myofilament function using small frozen biopsies that can be collected from different cardiac locations, from mice to men.
Overview
This protocol describes the extraction and assessment of cardiac function using skinned cardiomyocytes. It enables the measurement and modulation of myofilament function through small frozen biopsies from various cardiac locations.
Key Study Components
Area of Science
- Cardiac physiology
- Myofilament function
- Cardiomyocyte extraction
Background
- This technique clarifies the pathophysiology of cardiac diseases.
- It investigates the correlation between in vitro and in vivo parameters.
- It allows the study of myofilament function using small biopsies.
- Therapeutic interventions can be assessed in vitro.
Purpose of Study
- To provide a detailed protocol for extracting cardiomyocytes.
- To assess myofilament function and calcium sensitivity.
- To evaluate the impact of various solutions on cardiomyocyte behavior.
Methods Used
- Extraction of cardiomyocytes from myocardial samples.
- Mechanical disruption of tissue to obtain cell suspension.
- Selection and gluing of cardiomyocytes for measurement.
- Recording of force data during contraction and relaxation.
Main Results
- Stable values of active tension in permeabilized cardiomyocytes.
- Measurements of calcium sensitivity and force redevelopment.
- Impact of cardiomyocyte isolation on experimental results.
Conclusions
- Skinned cardiomyocytes are crucial for assessing cardiac function.
- Methodology allows for detailed analysis of myofilament properties.
- Results can inform therapeutic strategies for cardiac diseases.
Frequently Asked Questions
What are skinned cardiomyocytes?
Skinned cardiomyocytes are cardiac muscle cells that have had their membrane removed, allowing for direct access to the myofilaments for experimental analysis.
Why is temperature control important in this protocol?
Temperature control is crucial for maintaining the stability and functionality of the cardiomyocytes during experimentation.
How does this technique contribute to understanding cardiac diseases?
This technique allows researchers to study the fundamental properties of cardiac muscle function, which can reveal insights into the mechanisms of cardiac diseases.
What is the significance of calcium sensitivity in cardiomyocytes?
Calcium sensitivity is vital for understanding how cardiomyocytes contract and relax, which is essential for normal heart function.
What precautions should be taken during cardiomyocyte extraction?
Care should be taken to minimize cell damage during extraction and to ensure proper handling of the samples to maintain their integrity.
How can therapeutic interventions be assessed using this method?
Therapeutic interventions can be tested by observing their effects on myofilament function and calcium sensitivity in isolated cardiomyocytes.
Executive Industry Relevance
In vitro assessment of cardiac function using skinned cardiomyocytes provides a high-resolution platform for dissecting myofilament mechanics and drug effects at the cellular level. This approach enables predictive evaluation of therapeutic interventions and mechanistic de-risking in early cardiac drug discovery. The method supports translational continuity by correlating in vitro findings with in vivo cardiac function in both animal models and human tissue.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Enables direct interrogation of myofilament function and contractile mechanisms in disease-relevant cardiomyocytes.
- Supports biological de-risking by quantifying passive and active force parameters under controlled conditions.
- Facilitates predictive confidence in target engagement and mechanistic hypotheses for cardiac drug programs.
Screening & Assay Development
- Provides a validated system for measuring force development, calcium sensitivity, and cooperativity in response to compounds.
- Enables assay standardization and reproducibility using small, well-characterized myocardial samples.
- Supports quantitative readouts for compound screening and functional profiling of drug candidates.
Translational & Preclinical Research
- Aligns in vitro myofilament data with in vivo cardiac function for translational biomarker development.
- Enables assessment of therapeutic interventions across species, cardiac regions, and pathological states.
- Supports risk-adjusted advancement decisions by clarifying cellular mechanisms underlying cardiac phenotypes.
Pipeline & Workflow Integration
This method integrates into the discovery-to-preclinical continuum by providing mechanistic insights and quantitative outputs for cardiac target validation and lead optimization.
- Discovery Biology: Supports hypothesis testing and pathway clarification by isolating myofilament-specific effects.
- Screening: Delivers reproducible, quantitative force and calcium sensitivity measurements for compound evaluation.
- Analytics: Generates data on maximum force, pCa50, nHill, and ktr to compare drug and genetic perturbations.
- Translational Research: Bridges in vitro cellular findings with in vivo cardiac outcomes in animal and human models.
- Enterprise Reuse: Applicable across diverse cardiac samples, enabling broad portfolio support and cross-program standardization.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence and reduces mechanistic ambiguity in cardiac drug discovery.
- Operational Value: Enables standardized, scalable, and reproducible assessment of cardiomyocyte function.
- Strategic Value: Improves go/no-go decisions and capital efficiency by clarifying drug effects at the myofilament level.
- Portfolio Impact: Supports risk-adjusted prioritization and advancement of cardiac programs based on robust cellular data.
Implementation Considerations
- Requires expertise in cardiomyocyte isolation, handling, and force measurement instrumentation.
- Demands precise temperature control and analytical infrastructure for reproducible results.
- Necessitates cross-team standardization of protocols and data analysis workflows.
- Adaptable to a range of species, cardiac regions, and pathological samples with minimal tissue requirements.
- Results are sensitive to cell isolation quality and experimental handling, impacting data reliability.
Biopharma FAQs
Why does null hypothesis testing matter for myofilament force measurements?
Null hypothesis testing in myofilament force measurements enables objective evaluation of drug or genetic effects on cardiomyocyte contractility, supporting robust target validation and reducing false positives in early discovery.
How does independent variable isolation fit the skinned cardiomyocyte workflow?
Isolating variables such as calcium concentration or compound exposure in skinned cardiomyocyte assays allows precise attribution of observed force changes to specific interventions, strengthening mechanistic confidence in discovery pipelines.
What do quantitative dependent variable measurements enable in this assay?
Quantitative measurements of force, calcium sensitivity, and rate of force redevelopment provide actionable data for comparing drug effects, optimizing lead compounds, and informing translational biomarker strategies.
Why are replication requirements critical for cross-functional cardiac studies?
Replication of force and sensitivity measurements across multiple cardiomyocytes and samples ensures data reliability, enabling cross-functional teams to make confident decisions on target engagement and compound advancement.
What statistical analysis capabilities are required before implementing force redevelopment assays?
Robust statistical analysis is needed to interpret force redevelopment and calcium sensitivity data, including comparison of means, variance assessment, and significance testing to support portfolio-level decision making.
Chapters in this video
0:04
Introduction
1:00
Skinned Cardiomyocyte Extraction and Permeabilization
2:46
Skinned Cardiomyocyte Selection and Gluing
4:03
Active, Passive and Calcium (Ca2+) Sensitivity Force Measurements
5:58
Results: Representative Skinned Cardiomyocyte Assessment
7:36
Conclusion
