Cell culture grows cells in vitro for life science research and biomanufacturing. Cell culture processes to manufacture biologics come in three broad categories: batch, fed batch, and continuous culture. Common cell types for manufacturing include various mammalian, yeast, and insect cells.
Since adherent cells are anchorage-dependent, they require attachment to a solid or semisolid substrate like microcarriers. Nonadherent cells simply grow through suspension culture while floating in the medium.
Cell culture conditions
Cell culture conditions differ widely for varying cell types. Basic environmental requirements are:
- A regulated physical and chemical environment with monitored pH, temperature, and osmotic pressure.
- A growth medium or substrate to provide nutrients such as carbohydrates, amino acids, minerals, and vitamins.
- A steady supply of oxygen (O2) to keep pace with aerobic cellular metabolism.
- Media culture supplements and feeds, as needed. These may be added to serum-free cultures or to cultures that contain low levels of serum such as fetal bovine serum.
Types of cell culture media
These come in two major categories: natural and artificial media.
a) Natural media
Natural cell culture media come from naturally occurring biological fluids. These types of media contain many factors that are unknown and that may vary widely. As a result, this class of media often has low reproducibility.
b) Artificial media
Artificial and synthetic cell culture media formulations contain components that are partially or completely characterized. One category of artificial media is serum-containing media, which is also known as classical media. Medium that contains serum is often used in research or in certain manufacturing processes that still use serum, such as producing viral vectors.
The other category of artificial media is serum-free media, also sometimes called specialty media. Serum-free media can be further divided into the following types, which may overlap:
- Animal-derived component-free media – do not contain any ingredients that come from an animal source
- Protein-free media – do not contain large proteins
- Chemically defined media – contain only known ingredients that are well characterized
To ensure peak cell proliferation, serum-free growth media is often enriched with media culture supplements.
Cell culture supplements FAQs
Below are answers to some frequently asked questions about media culture supplements.
What are media culture supplements?
Supplements are media additives that improve the growth and viability of cells under serum-free and low-serum conditions.
What are the different medium supplements?
A wide range of options are available. Some of the more common ones include:
- Amino acid supplements – with L-glutamine and other amino acids to support the growth of cells that have high energy demands and synthesize large amounts of proteins and nucleic acids
- Sodium pyruvate – an easily accessible carbohydrate source, often used for CHO cells
- Supplements for glutamine synthetase, such as GS-Max media supplement, developed to meet the specific requirements of GS-NS0 cells to provide the nutrients necessary for achieving a high level of monoclonal antibody (mAb) production
- Cholesterol supplements – to support high-cell density fed-batch bioreactor cultures