Generate Stable CHO Cell Lines
Using the CHOgro® High Yield Expression System, exceptional yields of recombinant protein can be obtained by transient transfection of suspension CHO cells. Though transgene expression ceases for the vast majority of cells within one to two weeks post-transfection, a small fraction of transfected CHO cells continues to stably express the recombinant protein through random chromosomal integration of the transfected gene. In this Tip from the Bench, we share a protocol for generating stable cell lines through selection and expansion of CHO cells which produce high levels of recombinant protein.
Maintain Suspension CHO Cells
Suspension CHO cells have emerged as one of the most important cell lines for protein expression in biomanufacturing for their capacity to grow to high cell density in serum-free medium. Successful cell growth of these popular cells is dependent on several factors, which include media composition, culture format and appropriate cell maintenance. In today’s Tip from the Bench, we share a few tips for keeping your suspension CHO cells in transfection-ready shape!
Crossing the BBB with Nanobodies
The blood brain barrier (BBB) protects our brains from circulating pathogens and inflammatory cells. However, it also prevents the delivery of therapeutics into the brain. In this SNiP, we highlight a study from Rué et al. that describes a bispecific nanobody construct that can bind an Alzheimer’s disease target as well as a receptor at the BBB interface to promote entry into the brain.
Media Adaptation for Suspension Cells
The success of an experiment can rely on the type of cell culture media used. In certain cases, you may need to adapt your current cell culture to a new medium. A stepwise process may be necessary to minimize stress and to retain normal cellular phenotype. Check out this Tip from the Bench to learn how to gradually adapt suspension cells to a new media formulation.
Adapt Adherent CHO Cells to Suspension Culture
Chinese Hamster Ovary (CHO) cells are a popular workhorse for production of recombinant therapeutic proteins. Amenable to both adherent and suspension culture, CHO cells offer versatility in growth platform that is favorable to the end user’s requirements.
In this Tips from the Bench, we highlight factors that differentiate adherent and suspension CHO cell cultures. Also, we describe a simple protocol for transitioning adherent CHO cells to suspension growth (and serum-free medium, if required).
Extending Viability in CHO Cells
A common question we encounter is: how can I extend CHO cell viability through the process of protein production? One common practice to maintain higher viability is to shift cell cultures to mild hypothermic conditions, e.g. 37°C to 32°C. Here, we discuss a hot (er… cold?) tip involving the CHOgro® High Yield Expression System, which also supports additional flexible protocol options for researchers who cannot shift cultures to 32°C or who desire extended cellular viability beyond one week following transfection.