Author: oetltd

We are baculovirus expression specialists. Providing support and services in an ever changing research environment.

Storing Insect Cells at -80°C?

Every so often we are asked if storing insect cells at -80°C is a viable option if you haven’t got access to liquid nitrogen cryogenic facilities.  Our standard response is that this is not a good idea for long term storage of viable cells.  This is largely based on historical dogma that says that cells do not preserve their viability for long at these temperatures.  However, since one of our protocols for freezing insect cells involves an overnight cooling step in propanol in the -80°C we thought we would test the longevity of Sf21 cells left at this temperature for a little while longer.  (more…)

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When to Passage Sf9 Cells

An important factor in baculovirus expression is assessing when to passage Sf9 cells, which are commonly used to make recombinant viruses or for protein production.  In our last blog we talked about how to make the transition from monolayer to suspension cultures and how maintain cells in a healthy state during this time. To define what is meant by ‘healthy’ cells,  Figure 1 shows a sample of healthy Sf9 cells which appear largely uniform in size and round. What doesn’t come across in a web-based image is how the cells have a ‘shiny’ appearance.  Although hard to define, when you see it you will recognize it! (more…)

Suspension Sf9 Cells from Monolayer Cultures

The transition to suspension Sf9 cells from monolayer cultures is not difficult but does depend on harvesting the attached cells at the right time. Too early and it is extremely hard to detach the cells from the culture flask. Too late and the cells will be in such poor condition that they may not recover when in suspension. Trying to describe in words how the monolayer culture should look prior to harvest is difficult. Therefore, we have prepared a series of images depicting Sf9 cells from just after they were dispensed into a monolayer culture to the point of harvest for transition to suspension. (more…)

Co-infection with Baculovirus Vectors for Multiple Protein Expression

A question that comes up from time to time is the use of co-infection with baculovirus vectors for multiple protein expression in insect cells.  The need arises if you have produced a number of baculovirus vectors that each synthesise a component of a multi-subunit complex, such as an enzyme or a virus like particle.  Intuitively, you know that it is probably necessary to add many virus particles per cell to achieve efficient infection with each recombinant.  But how many viruses can you add to each cell and still get each one into every cell in equal numbers? (more…)

Variable Expression of Multi-Component Protein Complexes

Variable expression of multi-component protein complexes is increasingly necessary as more sophisticated projects are attempted.  But how can this be achieved?  Most of our expression work is based on the baculovirus system, in particular our flashBAC™ vectors that permit easy recombinant virus generation in a one-step process.  These insect-specific viruses offer an ideal platform for producing a wide range of recombinant proteins including nuclear, cytoplasmic, membrane-bound and secreted examples. (more…)

Intermediate scale recombinant protein production

Between initial tests and larger scale up you may want to conduct intermediate scale recombinant protein production using baculovirus vectors.  If you are working with several constructs then this can begin to get expensive of cell culture vessels such as the ubiquitous 125ml conical flasks, in which you can amplify 25-30mls of virus-infected cells.  Space on shakers can also be at a premium in some labs. (more…)

Welcome!

Oxford Expression Technologies are the experts when it comes to the science of baculovirus. For almost 10 years now we have specialised in recombinant protein production in insect cells and the ‘Bac to the Future’ blog is the culmination of this extensive knowledge.

Written by our in-house scientists, articles cover every aspect of the baculovirus system – from its discovery and background, to practical applications in research and industry. We cover both the day-to-day challenges and more complex cases faced by ourselves and customers. You can also keep up to date on all the news, developments and promotional offers from the company.

If you have a question about any of the content featured, or simply want more information on a particular topic, then do not hesitate to get in touch with us directly at info@oetltd.com. In addition, OET offers everything needed to aid your own insect virus research. As creators of the world renowned flashBACTM technology, our range of baculovirus expression vectors are designed for simple and rapid recombinant protein production. This is supported by an optimised range of transfer plasmids, transfection reagents, and cell culture media to ensure a powerful and versatile system. Browse the full collection of products at https://oetltd.com/shop/

We hope you enjoy.

-OET