Technique Tuesday: Mammalian Cell Culture

Oct 28, 2020
By Whitney Bell

Technique Name: Mammalian Cell Culture

Difficulty Rating:

4/5 petri dishes depending on the day. Mammalian cell culturing can be simple if you’re using immortalized cell lines (like fast-growing cancer cells; however, can be more difficult and time consuming if you are using primary cells lines to make sure they are not differentiating or becoming contaminated with microorganisms.

What is the general purpose? The purpose of culturing cells is to have a system with fewer variables (one type of cell versus an entire organism with lots of different cell types) in order to study and answer questions about basic biology, biochemistry, metabolism, and more.

Image from Thermo Fisher Scientific

Why do we use it? We remove cells from living organisms, such as humans and other animals and grow them in an artificial environment to have a model system to work with when studying the physiology and biochemistry of an organism. Culturing cells allows us to extract the biological molecules of interest such as DNA, RNA, and proteins and use them for numerous types of experiments. Cell culture is both time and cost-effective. It is also a simpler method than using the whole organism, which in the case of studying human cancers and drug treatments, might not be possible.

Image from lifelinecelltech

How does it work? Cell culture is a popular technique used in many laboratories to study a variety of fields such as drug treatment, drug metabolism, and cancer development. This technique also provides the biological material needed, such as protein, DNA, and RNA, for a variety of experiments that scientists use to investigate their hypotheses, like if a novel drug compound could be used to treat cancer.

Before a new drug or vaccine can move to human clinical trials it must first be vigorously tested for safety and efficacy. If the drug is meant to be used as part of a chemotherapy treatment for human colon cancer, colon cancer cells taken from standardized cell lines or taken directly from patients are tested first. The testing then moves to animal models, such as mice, and if successful, eventually moves to human clinical trials.

Depending on the cell type, the cells can be cultured in a few different ways. Cells such as skin fibroblasts are grown in plates because these cells need a surface to grow on. These are called “adherent cells”. These cells will grow on the bottom of the plates and are covered in liquid we call “media”. The media provides the optimal pH and nutrients the cells need to grow and proliferate, which they would normally obtain from the living organism. Other cell types, such as those found in the blood, are called “suspension cells” because they do not need a surface to grow on. Rather, they grow while floating in media, similar to how they grow in the body while circulating through the bloodstream.

The media the cells grow in must be changed on a regular basis so that the cells receive a continuous supply of nutrients, and the cell culture dishes must be kept in incubators, typically kept at 98.6°F (37°C), which is the standard for body temperature.  The density at which the cells are kept at also plays a role in how they grow, so you must monitor how many cells are in your plate.

In summary, cell culture is an incredibly important technique that is used by scientists in dozens of biological fields. It provides valuable insight into how cells and their subcellular components, such as proteins, react to various stimuli and treatments, and is the first step in the medicinal development pipeline.

Image credit to Lubna Hussain, Senior Global Product Manager, Lonza

Edited by Rohan Parekh and Taylor Tibbs