Related Experiment Video
Updated: Jul 15, 2026
10:48
Vaccinia Reporter Viruses for Quantifying Viral Function at All Stages of Gene Expression
Published on: May 15, 2014
Measuring herpes simplex virus thymidine kinase reporter gene expression in vitro
Shahriar S Yaghoubi1, Sanjiv S Gambhir
1Department of Radiology, Molecular Imaging Program at Stanford, Stanford University School of Medicine, Clark Center, 318 Campus Drive, E150, Stanford, CA 94305-5427, USA.
Nature Protocols
|May 10, 2007
Summary
Two assays evaluate herpes simplex 1 virus thymidine kinase (HSV1-tk) gene expression for preclinical research. These methods assess enzyme activity or cell uptake, validating molecular models before in vivo studies.
Area of Science:
- Molecular imaging
- Reporter gene technology
- Biomedical research
Background:
- Herpes simplex 1 virus thymidine kinase (HSV1-tk) and its mutant HSV1-sr39tk are crucial positron emission tomography (PET) reporter genes.
- These genes enable investigation of intracellular molecular events and cell trafficking in vivo.
- Validating reporter gene expression in vitro is essential before in vivo application.
Purpose of the Study:
- To describe and compare two in vitro methods for assaying HSV1-tk and HSV1-sr39tk gene expression.
- To highlight the utility of these assays in validating molecular models for preclinical research.
Main Methods:
- Enzyme activity assay: Measures radiolabeled substrate phosphorylation by HSV1-TK or HSV1-sr39TK in cell lysates.
- Cell-uptake assay: Incorporates cellular substrate uptake and efflux characteristics alongside enzyme activity.
- Both assays utilize radiolabeled substrates and are completed within one day.
Main Results:
- Two distinct in vitro assays are presented for quantifying HSV1-tk and HSV1-sr39tk activity.
- The cell-uptake assay provides a more comprehensive assessment by including cellular transport dynamics.
- Both methods offer reliable validation of molecular models in cultured cells.
Conclusions:
- Established in vitro assays enable robust assessment of HSV1-tk and HSV1-sr39tk reporter gene expression.
- These assays are critical for validating preclinical molecular imaging models.
- The described methods facilitate efficient and timely validation prior to in vivo studies.
