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University of Gothenburg
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Staff working at the ÄKTA workstation at MPE
Photo: Charbel Sader
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How to Access the MPE Services

We help you to produce proteins for your research. In our cell culture lab, our staff performs all the work (because of the risk of contaminations in a cell culture lab), but you can help with other parts of the work.

This includes vector constructions and analyses of proteins that we have produced, depending on your know-how and experiences. If you want we can perform all the steps. Please contact us to discuss the design of a project for your proteins.

Produce a Protein

At MPE we produce recombinant proteins in mammalian cells, an expression system that can produce large, secretory proteins with post-translational modifications such as glycosylations, disulfide bonds and proteolytic cleavages.

We help you to produce proteins for your research. In our cell culture lab, our staff performs all the work (because of the risk of contaminations in a cell culture lab), but you can help with other parts of the work. This includes vector constructions and analyses of proteins that we have produced, depending on your know-how and experiences. If you want we can perform all the steps. Please contact us to discuss the design of a project for your proteins.

A typical work-flow can be as follows:

1. Vector construction. The cDNA encoding your protein of interest must be cloned into an expression vector for mammalian cells. If you have the possibility, you can perform this step yourself, or we can do it at MPE. We can also help with the ordering of commercially generated vectors.

2. Transfection and cloning. The vector will then be transfected into cells for the generation of stable, producing clones. Analysis of the clones can either be done at MPE or can be done by you.

3. Adaptation. A selected high-producing clone has to be adapted to growth in suspension in serum-free medium prior to a bioreactor can be run for production.

4. Bioreactor run. When a clone is well-adapted, it can be cultured in a bioreactor for production of a larger batch of the recombinant protein. We use perfusion culture where culture supernatant is harvested continuously and we normally collect between 10 and 20 L, depending on the productivity of the clone and how much protein is wanted.

5. Product concentration and purification. The harvested medium is then concentrated by tangential flow filtration, down to volumes that are easier to handle and then purified by for example affinity chromatography.

6. Product analysis. SDS-PAGE, Western blots or ELISAs of the produced protein can be performed throughout the different steps, either by MPE or by you.

As an alternative to this workflow, we can also produce proteins through transient transfection of CHO or HEK293 cells in litre-scale. Steps 2-4 above are then replaced by a larger transfection of many cells, which is performed in our bioreactors. This is a good alternative to get the protein somewhat faster.

In the post-genomic era, the need for the expression of predicted proteins to study their functions will be increasingly important. Many small or intracellular proteins can be expressed in bacteria, yeast or insect cells, but larger mammalian proteins, especially the secreted ones, cannot be expressed in these systems. The reason for this is the specific folding and exit control system of the endoplasmic reticulum and the specific glycosylation found in mammalian cells. For the production of larger, mammalian proteins, Chinese Hamster Ovary (CHO) cells has been the cell line of choice in several instances, both within the European Union “Animal Cell Factory” projects and within the Biotech Industry. It is also the main cell line we use at MPE for this purpose. CHO cells have some advantages in that 1) they can be adapted to single-cell suspension growth, 2) they have an efficient protein folding machinery and 3) products from CHO cells are considered safe for use as human therapeutic agents.

The scientific staff of MPE have experience of several EU-financed consortia for the recombinant expression of variable and specific glycoforms of proteins for vaccination trials against breast cancer. This has taught us how to utilize CHO cells for recombinant protein expression and ways to manipulate the glycosylation in these cells (both O- and N-glycans). In these EU projects, we have collaborated with Prof. Thomas Noll at the University of Bielefeld, Germany, formerly at the Biotechnology Research Centre in Jülich, Germany, one of the largest and best facilities for the production of recombinant proteins outside of the biotech industry in Europe. Our two groups have together adapted and tested conditions for the efficient production of this recombinant vaccine. It was found that glucose-limited perfusion cultures (a continuous culture system where medium is added continuously and used medium is pumped out at the same rate) were superior in terms of productivity. In addition to the high secretion, the recombinant proteins were easily harvested from the culture supernatant at a high purity. As we are using protein-free medium, more than 50% purity can be obtained directly after a simple concentration step. The group of Prof. Noll is involved in the setting up and running of the MPE facility. Thus, all their expertise in bioprocess development will be made available to the customers of the facility.

Culture Cells

Our staff performs cell cultures for researchers who need cells, from for example cell lines, in different amounts. We also have a cell culture lab that is for rent for researchers who temporarily needs to culture cells, for example for microscopy studies.

For cells growing attached to a plastic surface, we have a roller bottle culture system that can generate large surface areas with minimal medium volume requirements.
For cells growing in suspension, we have spinner bottles for the culture of volumes up to 300 ml. In addition, we have a shaking incubator for E flask cultures. We also have 1 and 3 litre bioreactors for perfusion culture for more optimized culture conditions, giving a higher yield of protein (up to a total of 20 liters of media).  This will be the culture method of choice for the large-scale production of secreted recombinant proteins in for example Chinese Hamster Ovary (CHO) cells.

This means that we have the ability to culture many different types of cell lines. If you have an interest in having a cell line cultured at MPE, please contact us.