BacMam VectorGene expression in mammalian cells
BacMam is a BSL-1 modified baculovirus vector which efficiently transduces most mammalian cells – including primary cultures, cell lines, and iPSC derived cells. Researchers in life science and drug discovery have used BacMam for years to transiently deliver target receptors, genetically-encoded biosensors and other constructs in their cells of interest.
Montana Molecular’s biosensors, receptors, and optogenetic tools are packaged in BacMam because of its many benefits. Here we explore these benefits in an effort to explain why so many researchers are switching from plasmid transfection, stable cell lines and other viral vectors to using the BacMam system in their cells of choice.
BacMam provides a very even level of expression from cell to cell and plate to plate, providing near stable-line consistency in a transient model. Expression can be easily titrated to a level that is suitable to the experiment and sensor being used. Receptors packaged in BacMam, for example, can be titrated to express at near endogenous levels. Experiments are more consistent, repeatable, and reliable.
DAG sensor expressing in HEK293T cells, comparing BacMam transduction (left) and plasmid transfection (right)
Our BacMam-packaged sensors have been used successfully in many primary and iPSC-derived cells including neurons, pancreatic islets, and cardiomyocytes. BacMam is a great choice for examining these interesting, disease-relevant cells because of its low toxicity and effective expression which can last for several days. Let us know if you have questions about your specific cell type!
cADDis cAMP sensor expressing in Peri.4u iPSC derived peripheral neurons from Ncardia. Wide Field Fluorescence (left), Brightfield (right)
The transfection efficiency of the BacMam is excellent in hard-to-transfect cell lines like Calu-3s (>30-40% vs <10% with lipofectamine) and we can even achieve 5-10% transduction in macrophages, which are nearly impossible to transfect with cationic lipids.
Expression in human islets is pretty superb, after 18 hours of incubation. An excellent probe!
Assay is working beautifully with cardiomyocytes, showing a strong and immediate response.
We also like BacMam for its ease of use. Simply add BacMam to your cells, incubate for 20-24 hours, and conduct your experiments. Incubation times of 48 hours can be helpful when expressing red fluorescent constructs. Separate viruses containing multiple constructs can be added at once, and an optional HDAC inhibitor can boost and maintain expression.
There are no extra incubation steps that you would have in a typical plasmid transfection and antibiotic can be present in the media. The same BacMam virus can also be used across a variety of cell types, no need to create multiple stable lines expressing the same receptor or construct.
Custom BacMam Production
Over the past few years, several researchers looked to improve on plasmid transfection efficiency by switching to BacMam. In response to their requests, we have developed a system to package GPCRs, ion channels, and other constructs in BacMam, providing an effective transfection alternative.
BacMam is a low-cost alternative to plasmid transfection and creating stable cell lines. At ~$0.06 per well in a 96-well plate, it is a great alternative to transfection reagents such as lipofectamine ($0.08 per well, 96 well plate) and is considerably less of a commitment that purchasing or developing a stable cell line.
As BacMam has a nearly unlimited payload, we are able to add targeting sequences, cell-specific promoters, Cre-inducible systems, and more to our sensors to generate more precise tools for researchers. Our system allows for expression of larger constructs than plasmid transfection. Contact us for more information or to request tools that would be useful for your research.
The cilium is expressing our cADDis cAMP sensor, which was targeted using the full 5HT6 receptor sequence.