Constitutive and Inducible Systems for Genetic In Vivo Modification of Mouse Hepatocytes Using Hydrodynamic Tail Vein Injection
February 2nd, 2018
14.8K views
Hydrodynamic tail vein injection of transposon-based integration vectors enables stable transfection of murine hepatocytes in vivo. Here, we present a practical protocol for transfection systems that enables the long-term constitutive expression of a single transgene or combined constitutive and doxycycline-inducible expression of a transgene or miR-shRNA in the liver.
Overview
This article presents a method for stable transfection of murine hepatocytes in vivo using hydrodynamic tail vein injection of transposon-based integration vectors. The technique allows for long-term expression of transgenes or miR-shRNA, which can be induced by doxycycline.
Key Study Components
Area of Science
- Neuroscience
- Gene therapy
- Liver research
Background
- Stable transfection is crucial for studying gene function in vivo.
- Hepatocytes play a key role in liver function and disease.
- Inducible gene expression systems allow for temporal control of gene activity.
- Hydrodynamic injection is a technique used to deliver DNA to liver cells effectively.
Purpose of Study
- To establish a reliable method for stable transfection of hepatocytes.
- To enable the study of liver cancer mechanisms and regeneration.
- To facilitate the combined expression of CreER and inducible transgenes or shRNA.
Methods Used
- Hydrodynamic tail vein injection of transposon-based vectors.
- Combination of entry vector with short hairpin RNA and pTC Tet vector.
- Use of TE buffer for optimal vector preparation.
- Demonstration of the procedure by a laboratory med student.
Main Results
- Successful stable transfection of murine hepatocytes achieved.
- Inducible expression of transgenes and shRNA confirmed.
- Method demonstrated potential for liver research applications.
- Combined expression of CreER and transgenes was effective.
Conclusions
- The hydrodynamic tail vein injection method is effective for hepatocyte transfection.
- This technique can advance research in liver cancer and regeneration.
- Future studies can leverage this method for various gene expression investigations.
Frequently Asked Questions
What is hydrodynamic tail vein injection?
It is a technique used to deliver DNA into liver cells by rapidly injecting a large volume of solution into the tail vein.
What are the advantages of this transfection method?
It allows for stable transfection and long-term expression of genes in hepatocytes, facilitating various research applications.
How does the inducible expression work?
Inducible expression systems can be activated by specific compounds, such as doxycycline, allowing for controlled gene expression.
What applications can this method be used for?
It can be applied to study liver cancer mechanisms, regeneration, and other liver-related research areas.
Who demonstrated the procedure in the study?
The procedure was demonstrated by Eric Hubner, a medical student from the laboratory.
What is the significance of using shRNA?
Short hairpin RNA (shRNA) is used to silence specific genes, allowing researchers to study gene function and regulation.
Executive Industry Relevance
This method enables stable, inducible genetic manipulation of hepatocytes in vivo, supporting target validation and mechanistic de-risking in liver disease models. It provides a scalable approach for preclinical studies of liver cancer, regeneration, and fibrosis by combining constitutive CreER with inducible transgene or shRNA expression. The system enhances predictive confidence in therapeutic hypothesis testing through reversible, dose-dependent gene modulation in a physiologically relevant context.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Scientific Value: Enables interrogation of therapeutic hypotheses via inducible transgene or shRNA expression in hepatocytes.
- Scientific Value: Supports functional target validation through reversible gene modulation in disease-relevant models.
- Operational Value: Reduces mechanistic ambiguity by allowing temporal control of gene expression post-integration.
Screening & Assay Development
- Scientific Value: Generates quantitatively measurable outputs such as luciferase bioluminescence for longitudinal tracking of transfected cells.
- Operational Value: Produces standardized, reproducible hepatocyte transfection efficiency via hydrodynamic tail vein injection.
- Operational Value: Enables platform reuse across multiple inducible systems (e.g., doxycycline, tamoxifen) in the same animal cohort.
Translational & Preclinical Research
- Scientific Value: Maintains disease relevance by enabling genetic manipulation in primary hepatocytes within intact liver physiology.
- Scientific Value: Supports translational biomarker alignment through immunostaining of GFP or luciferase reporters in tissue sections.
- Operational Value: Facilitates risk-adjusted advancement decisions by linking inducible expression phenotypes to histopathological outcomes.
Pipeline & Workflow Integration
The method integrates into the discovery continuum from target validation through preclinical evaluation, enabling iterative testing of genetic interventions in liver disease models.
- Discovery Biology: Supports hypothesis testing and pathway clarification via inducible gene knockdown or overexpression in hepatocytes.
- Screening: Delivers assay-ready systems with quantitative bioluminescent or fluorescent readouts for compound or genetic modifier evaluation.
- Analytics: Provides measurable dependent variables including bioluminescence intensity, immunostaining signal, and histological changes for comparative analysis.
- Translational Research: Connects discovery findings to preclinical validation through consistent, inducible expression in liver tissue over time.
- Enterprise Reuse: Establishes a reusable transfection platform applicable across multiple inducible systems and Cre/loxP-based models.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence by reducing false positives through inducible, reversible gene expression systems.
- Operational Value: Enhances reproducibility through standardized injection protocols and vector preparation workflows.
- Strategic Value: Improves capital efficiency by enabling multiple experimental inductions from a single transfection event.
- Portfolio Impact: Supports go/no-go decisions via clear, quantifiable endpoints such as luciferase signal attenuation or GFP reporter activation.
Implementation Considerations
- Requires molecular cloning expertise for transposon construct preparation and sequence verification.
- Depends on hydrodynamic injection capability, including precise volume control and high-speed delivery systems.
- Necessitates standardized induction protocols (e.g., tamoxifen, doxycycline) across study cohorts for reproducible results.
- Requires adaptation of promoter and reporter systems to match target gene expression patterns in hepatocytes.
- Limited by plasmid size constraints and potential transposon-induced genotoxicity, necessitating vector quality control.
Biopharma FAQs
Why does inducible CreER expression matter for target validation?
Inducible CreER expression allows temporal control of genetic modifications in hepatocytes, enabling researchers to distinguish between developmental and disease-related gene functions. This reversible system supports target validation by linking gene modulation to phenotypic outcomes after vector integration and clearance of non-integrated constructs.
How does hydrodynamic tail vein injection enable independent variable isolation in liver studies?
The method delivers transposon-based constructs specifically to hepatocytes, isolating the liver as the primary site of genetic manipulation. By controlling injection volume and speed, researchers achieve consistent transfection efficiency, allowing the independent variable (e.g., inducible transgene) to be isolated from systemic delivery variability.
What quantitative dependent variable measurements does luciferase bioluminescence enable?
Luciferase bioluminescence provides a longitudinal, quantitative readout of transfected hepatocyte presence and activity in vivo. Signal intensity measured via imaging systems enables comparison across conditions, time points, or induction levels, supporting statistical analysis of gene expression dynamics.
Why are replication requirements important for cross-functional collaboration in this method?
Replication ensures consistent transfection efficiency and inducible expression across animals, which is essential for reliable data sharing between biology, pharmacology, and pathology teams. Standardized protocols for injection, induction, and tissue processing minimize variability and support reproducible conclusions in multi-disciplinary liver disease models.
What statistical analysis capabilities are required before implementing inducible shRNA screens?
Implementing inducible shRNA screens requires baseline normalization of bioluminescence or fluorescence signals and power calculations to detect meaningful knockdown effects. Longitudinal data collection enables time-series analysis, while appropriate controls (e.g., non-induced, scrambled shRNA) support differential expression testing with false discovery rate correction.
Chapters in this video
0:05
Title
0:52
Recombinatorial Cloning to Generate Ready-for-injection Clones
2:23
Hydrodynamic Tail Vein Injection
4:22
Induction of Transfected CreER with Tamoxifen
5:33
Induction of Tetracycline-dependent Gene or shRNA Expression
6:35
Preparation of Mouse Liver for Analysis by Immunostaining
7:30
Results: Constitutive and Inducible Gene Expression in the Liver Following HTVI
8:47
Conclusion
