In Part II of our series on “Strategies for Improving Antibody Production in Hybridoma Cells,” we will look at ways to improve media to increase antibody yield and quality. Monoclonal antibodies produced in hybridoma cells are often used in research for developing new drugs, animal and toxicology studies on drugs that have potential and in the diagnostic industry. In each of these areas there is a need to produce high quality antibodies as quickly and efficiently as possible. Hybridoma cells do not typically go through the kind of scale up and process development that a CHO cell line would, so it is crucial that hybridoma media supplements be easy to use and provide clear benefits.

Historically hybridoma cells have been grown in base media plus fetal bovine serum (FBS), but there are problems with this kind of production, including FBS lot-to-lot variability and inconsistency. FBS and animal products in general are plagued by inconsistent product lots, mainly due to the fact that the source material (cows themselves) can be so different based on where they live, what they eat, etc. Some lots of FBS may contain little contamination, others significantly more and some lots may be higher in various nutrient or vitamin components. All of these inconsistencies have a major impact on cells, which makes manufacturing difficult because yield isn’t consistent. Customers can get around this by screening multiple lots and buying in large quantities, but these tests are time consuming and purchasing large lots ties up resources that could be spent elsewhere. In addition, FBS contains contaminating IgG that reduces overall antibody quality. In some cases, low IgG serum can be used to address the issue, but it is quite costly and still isn’t completely IgG free. Another resource drain associated with FBS is the sourcing and documentation surrounding purchasing FBS and ensuring that it is free of mad cow disease. These issues have driven many researchers to switch to a serum-free media for hybridoma production.

Serum-free media eliminates FBS issues, but often creates issues of its own, primarily a reduction in antibody yield. It can also be very difficult and time consuming to transition a cell line to serum-free conditions. Hybridoma cells typically take several passages to be weaned away from serum. To assist in the endeavor to become animal-free and maintain antibody yield, serum-free base media can be supplemented with innovative animal-free products such as recombinant albumin and recombinant transferrin that are completely IgG free. Today companies including Sigma, Fisher Scientific, InVitria, Sheffield Bioscience and Mediatech sell recombinant albumin and recombinant transferrin that can be added to base media to provide an alternative to using serum in hybridoma culture. InVitria has a supplement that is specifically designed for this purpose called Zap-Hybridoma. According to InVitria, Zap-Hybridoma can provide an animal-free replacement for fetal bovine serum (FBS) when used with DMEM-F12. One of InVitria’s customers, Peter Andersson, Mabtech AB said, “we were amazed to see how well our hybridomas were able to adapt to a serum free environment and maintain a stable viability and antibody production.” He continued “I would recommend the usage of InVitria’s Zap-Hybridoma to those who search for a completely serum free environment for their cells in order to avoid the contamination of bovine antibodies and other downsides from the usage of serum.” InVitria also manufactures ITSE Animal-free, a combination of recombinant insulin, transferrin, selenium and ethanolamine that is frequently used to transition hybridoma cells away from serum. MP Biomedicals also has a serum replacement product called TCH that can be used in hybridoma culture to replace serum. ThermoFisher Hyclone has a vitamin supplement called Cell Boost 3 used to increase the productivity and growth of serum-free hybridoma culture.

The advantage of these new animal-free products is that they eliminate the problems associated with serum, like inconsistency, IgG contamination and sourcing challenges, without the reduction in antibody yield that is common with serum-free media. They also reduce the transition time from serum containing to animal free culture conditions.

Has anyone used any of these products, if so, which ones and how did they work for you?